i I Java Java Java

Transcription

1 Masami WADA ver.3.2 ( ) (ver.3.2.2) 10 (ver.3.2.1) 9 (ver.3.2) (^_^;)

2 i I Java Java Java Eclipse Pleiades JDK JRE Java I I System.out.print System.out.println Unicode Javadoc

3 ii (integer type): byte, short, int, long (real number type): float, double : boolean : char if switch boolean for while do while break continue null for

4 iii Math Math System.in System.out Scanner(System.in) II System.out.printf() I API (Application Programming Interface) ( ) main System.arraycopy ( ) (Selection sort) (Insertion sort) (Bubble sort) (Quicksort) (Heap sort) (Merge sort) (Shell s sort) Java II Java Java II

5 iv private package-private protected public ( ) Object super final ( ) (Exception) Exception try catch finally Scanner next nextline File Scanner(File) FileInputStream / FileOutputStream FileReader / FileWriter BufferedReader / BufferedWriter InputStreamReader / OutputStreamWriter Java Excel Mathematica import import java.lang

6 v Generic Java API Collection ArrayList LinkedList Stack Queue static ( ) Thread Runnable JavaFX ( ) e(fx)clipse Scene Builder JavaFX Stage Scene enum

7 vi III Apx.1 A Apx.2 A Apx.2 A Apx.3 A Apx.4 A Apx.4 A Apx.5 A Apx.5 A Apx.5 A Apx.6 A Apx.7 A Apx.8 A Apx.8 A Apx.9 A Apx.10 A.9 IEEE Apx.10 A.9.1 IEEE Apx.10 A Apx.12 B Eclipse Apx.13 B Apx.13 B.2 Pleiades Apx.13 B.3 Java API Apx.14 B.4 Eclipse Apx.15 B Apx.15 B Apx.15 B.5 Java API Apx.17 B.6 Eclipse Apx.17 B.6.1 workspace Apx.17 B Apx.20 B.6.3 API Apx.20 B.6.4 Eclipse Apx.22 B.7 Eclipse Apx.25 C javadoc Apx.27 C.1 Javadoc Apx.27 C Apx.27 C.3 Javadoc Apx.31 D debug Apx.32 D Apx.32 D Apx.32

8 vii D Apx.32 D Apx.33 D Apx.33 D Apx.33 D Apx.33 D Apx.34 Ind.1

9 viii 2.1 HelloJava.java ( Duke) HelloJava2.java ( Duke ) UnicodeCheck.java (UNICODE ) Comments.java ( ) IntegerMaxAndMin.java ( ) RealNumberMaxAndMin.java ( ) CharIsInteger.java ( ) Substitution.java ( ) Arithmetics.java ( ) PAdditionValues.java ( ) SwapValues.java ( ) AdditionValues2.java ( ) CompoundAssignment.java ( ) ErrorSubst.java ( ) SubstInEquation.java ( ) SubstInEquation2.java ( ) MultipleSubst.java ( ) MultipleSubst2.java ( ) MultipleSubst3.java ( ) Casting1.java ( ) Casting2.java ( ) CompoundAssign.java ( ) IfElse.java (if else ) OddOrEven.java ( ) Vote.java ( ) RankEvaluation.java ( ) IsVariable.java (boolean ) DoubleCounter.java ( ) FibonacciNumbers.java ( ) NoMultiple.java (3 ) CollatzSequence.java ( ) WhileVSDoWhile.java (while do while ) InfiniteLoop.java ( )

10 ix 2.35 GuessingGame.java ( ) MultiplicationTable.java ( ) DoubleLoop.java ( ) DoubleLoop2.java ( break ) DoubleLoop3.java ( continue ) LoopParameter.java ( ) ArrayInitialization.java ( ) PrintArray.java ( ) ArrayInitialization2.java ( ) SumOfArray.java ( ) MaxOfArray.java ( ) AverageOfPositive.java ( ) OlympicGame.java ( ) DifferenceTwoArray.java ( ) SwapArray.java ( ) ToReverseOrder.java ( ) EvaluateGrade.java ( ) ShiftArray.java ( ) ArrayInitialization3.java ( ) StudentDegrees.java ( ) SetArrays.java ( ) ArrayIndexOutOfBounds.java ( ) ArrayCopy.java ( ) ArrayCopy2.java ( ) ArrayCopy3.java ( ) ExtendedForEach.java ( for ) ExtendedForEach2.java ( for ) ExtendedForEach3.java ( for ) MatrixVector.java ( ) MatrixMatrix.java ( ) TrigonometricTable.java ( ) MathMethods.java ( ) TriangulumArea.java ( ) OddEven.java ( ) QuadraticEquation.java ( ) TrigonometricTable2.java (printf ) NewtonMethod.java ( Newton ) CircleArea.java (main ) CircleArea2.java ( ) CircleArea3 ( ) SwapValues2.java ( ) FormalParameter.java ( )

11 x 2.77 LinearAlgebra.java ( ) FibonacciRecursive.java ( ) FactorialRecursive.java ( ) HanoiTower.java ( ) MainParameters.java ( ) ArrayCopyExample1.java ( ) ArrayCopyExample2.java ( ) ArrayCopyExample3.java ( ) ArrayCloneExample.java ( ) StringvsChar.java ( ) StringMethods.java ( ) MyTools.java ( ) SortingExample.java ( ) ArraySorting.java#selectionSort ( ) SortingExample.java#main ( ) ArraySorting.java#selectionSort ( ) SortingExample.java#main ( ) ArraySorting.java#bubbleSort ( ) SortingExample.java#main ( ) ArraySorting.java#quickSort ( ) SortingExample.java#main ( ) ArraySorting.java#heapSort ( ) SortingExample.java#main ( ) ArraySorting.java#mergeSort ( ) SortingExample.java#main ( ) ArraySorting.java#shellSort ( ) TimePrecisionExample.java ( ) WrongAverage.java ( ) SwapRowOfMatrix.java ( ) VectorNormalize.java ( ) Combination.java ( ) Maclaurin.java ( e ) MonteCarlo.java ( ) MargeArrays.java ( ) ArrayTransform.java ( ) InverseMatrix.java ( ) Student.java ( ) StudentExample.java ( ) Course.java ( ) ( ) StudentExample.java ( ) ( ) Student.java ( ) Point.java ( )

12 xi 3.9 PointExample.java ( ) ( ) Student.java ( ) MembershipExample.java ( ) Entry.java ( ) Member.java ( ) TaroExample.java ( ) ComplexNumberExample.java ( ) ComplexNumber.java ( ) MyMathExample.java ( Math ) CentroidExample.java ( Point[]) PrivateFieldExample.java (private field ) ( )PrivateFieldExample.java (private field ) InheritanceExample.java ( ) Human.java ( ) Professor.java ( ) Lecture.java ( ) Student.java ( ) PointExample3.java ( ) WeightedPoint.java ( ) ObjectExample.tex (Object ) ArrayIsObject.java ( Object ) StringIsObject.java ( == equals() ) PointExample4.tex ( ) ColoredWeightedPoint.java ( ) OverrideExample2.java ( ) SuperExample.java (supar. ) FinalParameter.java ( final) FinalExample.java (final ) OverrideExample3.java ( ) InstanceOfExample.java ( ) PolymorphismExample.java ( (?)) DivideZeroExample.java ( ) OutOfBoundExample.java ( ) ( ) DivideZeroExample.java ( ) TwoCatchExample.java ( ) RedirectExample.java ( ) FinallyExample.java ( finally ) MyExceptionExample.java ( ) ScannerExample.java ( ) ScannerExample2.java (next) ScannerExample3.java (nextline) ScannerExample4.java (Scanner )

13 xii 3.61 DelimiterExample.java ( ) ScannerExample5.java ( ) HelloJavaFromFile.java ( Duke) FileScanner.java (Scanner ) ScannerReadFile.java (hasnext() ) StreamExample01.java (FileOutputStream ) StreamExample02.java (FileOutputStream ) StreamExample03.java (FileWriter ) StreamExample04.java (BufferedWriter ) StreamExample05.java (OutputStreamWriter ) CSV Example.java (CSV ) ImportExamaple.java ( ) StaticImportExample.java ( ) AbstractClass.java ( (?)) InterfaceExample.java ( ) InterfaceExample2.java ( instanceof) InterfaceExample3.java ( ) BoxExample1.java ( ) BoxExample2.java ( ) BoxExample3.java ( ) IntegersToObjects.java (Integer Object ) IntegersToObjects3.java ( ) GenericMethod.java (Generic method ) IntegerExample.java (Integer ) ArrayListExample.java (ArrayList ) ArrayListExample2.java ( ArrayList ) Point.java (Comparable ) ShapesExample.java ( ) LinkedListExample.java (LinkedList ) StackQueue.java (Stack Queue ) students.txt ( ):src/section StudentListExample.java (main ) Student.java ( ) Date.java ( ) StudentCell.java ( ) StudentList.java ( ) BinarySearchTreeExample.java NestedClassExample.java ( ) InnerClassExample.java ( ) AnonymouseClassExample.java ( ) ThreadExample01.java (Thread ) ThreadExample02.java (Thread )

14 xiii ThreadExample04.java (Runnable ) BankBooks.java ( ) JavaFXExample01.java ( JavaFX) JavaFXExample02.java (JavaFX ) JavaFXExample03.java ( ) JavaFXExample04.java ( ) PlayCardExample01.java ( ) PlayCardExample02.java ( ) PlayCardExample new.java (enum ) RGBColor.java ( ) EnumImportExample.java ( ) DeprecatedExample.java ( : ) VariableArityExample.java ( ) C.1 Circle.java ( ) Apx.27 C.2 Point.java ( ) Apx.28 C.3 Circle.java ( ) Apx.29 C.4 Point.java ( ) Apx.30

15 I Java 1

16 2 1 Java (machine language) (compiler) ( ) (compile) (programming language) Java Java PS 4 Java A B Eclipse Java OK! ) Java Java 1.1 Java Java ( Java ) 1990 Sun Microsystems ( Oracle ) ( Oak ) C C ++ C Web 1996 Java Java 2017/9 ver. 9 ( 2018/2 ) Java

17 1.2 3 Java manual.xml Java (Object oriented) (paradigm : ) (^^;) 2 ( ) 3 Java Java 1.2 C ++ Java Java Windows OS Mac OS OS (Operating System) (^^;) C ++ OS OS Java JVM (Java Virtual Machine Java ) Java JVM OS Java Write Once, Run Anywhere. Windows OS Mac OS linux ( ) OS JVM ( ) ( ) Java C ) C ++ Java 2018 Python (!?) ( Java ) Youtube Instagram Web Python Google Java C ++ Python Java Python Python Java Java Python Eclipse Pleiades IDE (Integrated Development Environment ) Eclipse ( ) Java

18 4 1 Java Java Eclipse NetBeans IntelliJ IDEA Eclipse IBM Java plugin ( ) C ++ PHP Perl C D TeX Python Ruby JavaScript AspectJ Mathematica SQL UML Eclipse 2018/2 ver.4.7 (Oxygen) (Oxygen ) Pleiades ( ) Eclipse Eclipse Pleiades All in one ( ) pleiades Pleiades Eclipse Eclipse JDK JRE Java Eclipse 1.1 Java JVM JRE (Java Runtime Environment Java ) JRE Java Java JDK (Java Development Kit Java ) JDK Oracle OS JDK JRE JDK Eclipse JDK JRE Eclipse JDK JDK Eclipse JRE JVM : Java Virtual Machine OS: Operating System 1.1 JDK Eclipse ( )

19 5 2 Java I 2.1 Java HalloJava.java Eclipse Java Java (^_^) 2.1 package section0201; public class HelloJava { public static void main( String[] args ) { System.out.print( " " ); System.out.print( "Duke " ); HelloJava.java ( Duke) 2.1 Duke (Duke Java ) Java ( ) Eclipse Java 1 2

20 6 2 Java I Eclipse (F) (N) Java Java (P) (F) ( 2.2 ) ( ) Java src Java src src 2.3 ) 2.3 (1) src (W) 2.4 ) section**** **** 0 2

21 (2) 2.1 HelloJava section0201 Java (M) section0201 (F) section0201 src ( 2.5 ) 2.5 (3) ( ) (source code)

22 8 2 Java I (binary code) (^^;) package section0201; public class HelloJava { public static void main( String[] args ) { System.out.print( " " ); System.out.print( "Duke " ); public class HelloJava Java ( ) java HelloJava.java HelloJava java. ( ) section0201 (W) Java (M) HelloJava ( 2.6 ).java public static void main(string[] args) (V) (F) 2.6 (1) Eclipse ( 2.7 ) // TODO

23 (2) (?) (indent) ( 3 4 ) tab ( ) ( ) ( ) 1 1 package section System.out.print( ) 1 Java (F) (S) Command+s HelloJava.java HalloJava.java (e a) ( HalloJava.java) (Alt+Shift+T) (Alt+Shift+R)

24 10 2 Java I ( ) Eclipse (F) (S) Eclipse Eclipse ( ) JVM Java Eclipse JVM Eclipse HelloJava ( ) (R) (S) Java ( ) (R) Java (N) ( ) (W) (P) Java (class) HelloJava HelloJava 1

25 (source file).java ( HelloJava ) ( ) public public public public ( ) (^^;) A B A.java 2. public A B A.java 3. A public B A.java 4. public A public B A.java Java ( graphical_tools) ( graphicaltools) ( GraphicalTools) (under score: ) OS ( )

26 12 2 Java I ( jp.ac.tus.ed.jmwada.programmingexamples) Java Eclipse 2.8 Eclipse 2.8 ( J ) Java Eclipse Java OS (^^;).java.java ) ( ) ( )

27 2.3 I Eclipse workspace ( ) C:Yjava C:Yjava.workspace Eclipse Eclipse ( Eclipse ) 2.3 I HelloJava section0201 HelloJava 2 7 HelloJava public static void main( String[] args ) (3 6 ) main main System.out.print System.out.print package section0201; public class HelloJava { public static void main( String[] args ) { System.out.print( " " ); System.out.print( "Duke " ); System.out.print Java (console) Eclipse ( ) System.out print method : 3 2 ( ) System.out print System.out.print (^^) (double quotations) print (semicolon) ; Java

28 14 2 Java I Duke Duke HelloJava System.out.println print Yn println println ( ) (^^)b? 2.2 package section0203; public class HelloJava2 { public static void main( String[] args ) { System.out.println( " " ); System.out.println( "Duke " ); HelloJava2.java ( Duke ) HelloJava2.java section0203 Duke System.out println System.out printf ( ) ( ) print println println ln line

29 Duke println System.out.println(); HalloJava2.java 2.4 a Z ASCII ( :American Standard Code for Information Interchange) NUL DEL SP P ` p 1 SCH DC1! 1 A Q a q 2 STX DC2 2 B R b r 3 ETX DC3 # 3 C S c s 4 EQT DC4 $ 4 D T d t 5 ENQ NAK % 5 E U e u 6 ACK SYN & 6 F V f v 7 BEL ETB 7 G W g w 8 BS CAN ( 8 H X h x 9 HT EM ) 9 I Y i y A LF SUB * : J Z j z B VT ESC + ; K [ k { C FF FS, < L \ l D CR GS - = M ] m E SO RS. > N ^ n ~ F SI US /? O _ o DEL 2.9 ASCII ASCII ( 2.9 ) 16 A (10 65) A ASCII bits ASCII 8 bits 7 7 bits bit 0 ASCII 8 bits

30 16 2 Java I JIS Shift JIS Java ( ) (Unicode) Unicode Unicode Xerox Microsoft Apple IBM Sun Microsystems Hewlett-Packard JustSystems The Unicode Consortium 1993 Java Unicode Unicode A (^^) 2.3 UnicodeCheck.java (UNICODE ) package section0204; public class UnicodeCheck { public static void main( String[] args ) { System.out.println( "A Unicode " + Integer.toHexString( A ) ); System.out.println( " Unicode " + Integer.toHexString( ) ); System.out.println( " Unicode " + Integer.toHexString( ) ); System.out.println( " Unicode " + Integer.toHexString( ) ); A Unicode ASCII A Unicode Unicode ( ) ASCII ASCII 5C ASCII ( 5C) Unicode 00A5 Unicode 005C 2.5 ( )

31 NUL DEL SP P ` p 1 SCH DC1! 1 A Q a q 2 STX DC2 2 B R b r 3 ETX DC3 # 3 C S c s 4 EQT DC4 $ 4 D T d t 5 ENQ NAK % 5 E U e u 6 ACK SYN & 6 F V f v 7 BEL ETB 7 G W g w 8 BS CAN ( 8 H X h x 9 HT EM ) 9 I Y i y A LF SUB * : J Z j z B VT ESC + ; K [ k { C FF FS, < L \ l D CR GS - = M ] m E SO RS. > N ^ n ~ NUL DEL SP P ` p 1 SCH DC1! 1 A Q a q 2 STX DC2 2 B R b r 3 ETX DC3 # 3 C S c s 4 EQT DC4 $ 4 D T d t 5 ENQ NAK % 5 E U e u 6 ACK SYN & 6 F V f v 7 BEL ETB 7 G W g w 8 BS CAN ( 8 H X h x 9 HT EM ) 9 I Y i y A LF SUB * : J Z j z B VT ESC + ; K [ k { C FF FS, < L l D CR GS - = M ] m E SO RS. > N ^ n ~ F SI US /? O _ o DEL F SI US /? O _ o DEL 2.10 ASCII 3 2 // /* */ Javadoc /** */ 2.4 Comments.java ( ) package section0205; public class Comments { int x = 10; // // int y = 20; 2 /* int z = 30; */ /* * Eclipse * */ /**

32 18 2 Java I * Javadoc C */ Eclipse 5 ( ) warning ( ) Eclipse x x Eclipse Eclipse 2.11 Eclipse ( 2.11 'unused' 'x' Enter Suppress warnings unused "unused" ) 1 (annotation: ) Java 5 Java ( ) ( ) // 1

33 ( x = 1; // x 1 ) ( // x 1 x = 1; ) 2 ( ) Eclipse Ctrl + 7 Ctrl + / // /* */ Eclipse Ctrl + Shift + / Ctrl + Shift + \ Javadoc C ( ) Javadoc Javadoc /** (* 1 ) */ 2.6 Java (primitive type) (reference type) 3 (floating point number type)

34 20 2 Java I (integer type): byte, short, int, long byte ( ) 8bits short ( ) 16bits int ( ) 32bits long ( ) 64bits = Java OS int 32bits C int 16bits 32bits bits 1bit bit bits Mathematica byte 8bits 1bit 7bits Mathematica Shift+Enter 127 byte 128 int 32bits long 1234 long 1234L 1234l ( l L) 64bits int short byte 2.5 IntegerMaxAndMin.java ( ) package section0206; public class IntegerMaxAndMin { System.out.println( " " ); System.out.println( "byte "); System.out.println( " = " + Byte.MIN_VALUE ); System.out.println( " = " + Byte.MAX_VALUE ); System.out.println( "short "); System.out.println( " = " + Short.MIN_VALUE ); System.out.println( " = " + Short.MAX_VALUE ); System.out.println( "int ");

35 System.out.println( " = " + Integer.MIN_VALUE ); System.out.println( " = " + Integer.MAX_VALUE ); System.out.println( "long "); System.out.println( " = " + Long.MIN_VALUE ); System.out.println( " = " + Long.MAX_VALUE ); (real number type): float, double Java (floating point number type) (fixed point number type) (^^;)? Java float ( ) 32bits IEEE754 double ( ) 64bits IEEE754 IEEE (Institude of Electrical and Elctrinics Engineers) 754 IEEE IEEE ( double float double float float 12.34F 12.34f double 12.34D 12.34d ( ) ( ) ( A ) 2.6 RealNumberMaxAndMin.java ( ) package section0206; public class RealNumberMaxAndMin { System.out.println( " " ); System.out.println( "float " ); System.out.println( " = " + Float.MIN_VALUE ); System.out.println( " = " + Float.MAX_VALUE ); System.out.println( "double " ); System.out.println( " = " + Double.MIN_VALUE );

36 22 2 Java I System.out.println( " = " + Double.MAX_VALUE ); float 7 double : boolean etc. Java boolean ( ) true ( ) false ( ) x = 1 true false (1) x + 1 = 2 (2) 4 < x (3) 0 < x x < 2 (4) x < 0 2 < x C boolean false 0 true 0 2 < 1 0 C ++ boolean bool true, false C false true false true Java : char char char ( character!? ) char ( forum=3) (^^) int long char ( ) Unicode 29356(=0x72AC) CharIsInteger.java ( ) package section0206; public class CharIsInteger { System.out.println( " " ); System.out.println( " " + (int) ); System.out.println( "16 " + Integer.toHexString( ) );

37 System.out.println( " = " + (char)( + 127) ); Java long ( ) Java double ( ) Java Java ( ) ( ) $ Java int ( ) Java

38 24 2 Java I xy 2. x-y 3. $xy 4. 10xy 5. xy 6. int 7. main 8. Class main Class Java main Class Java abstract assert boolean break byte case catch char class const continue default do double else enum extends final finally float for goto if implements import instanceof int interface long native new package private protected public return short static strictfp super switch synchronized this throw throws transient try void volatile while Java Unicode ( 0 ) int x Java int x int x; int x y int x, y; C 1 1 ( int x; int y; 2 ) = ; x 10 x = 10; Java =

39 = 10; 10 = x; int x = 10; 2.8 package section0207; public class Substitution { byte i = 12; short j = 123; int k = 12345; long l = L; float x = f; double y = ; boolean b = true; char c = 'A'; Substitution.java ( 'unused' 'main()' Java ( double x = 123;) ( int y = ;) int long float double ( int i = 1L; ) byte i = 12; short j = 123; (^^) byte short long ( L ) 2 int 12 [ 128, 127] byte i = 12; OK byte i = 200; Java byte x = 1234; 2. short x = 1234; 3. int x = 1234; 4. long x = 1234; 5. long x = ; 6. float x = 1234; 7. float x = ; 8. double x = f; 9. double x = 1234L;

40 26 2 Java I 2.8 Java + ) % / + / % 5 % ( 1.2 % 0.5 = ) (arithmetic operator symbol) println 2.9 package section0208; public class Arithmetics { System.out.println( ); System.out.println( 13-5 ); System.out.println( 13 * 5 ); System.out.println( 13 / 5 ); System.out.println( 13 % 5 ); Arithmetics.java ( ) / int int int 30 int double double /5 int int int 2 ( ) /5, 13/5.0, 13./5. OK x x 1. int x = ; 2. int x = 11-4; 3. int x = 11 * 4; 4. int x = 11 / 4; 5. int x = 11 % 4; 6. double x = 11 / 4; 7. int x = 11.0 / 4; 8. double x = 11.0 / 4; 9. int x = 1 / 2; 10. double x = -1.0 / 2; 11. int x = -1 / 2.0;

41 int x y x + y int z PAdditionValues.java ( ) package section0208; public class AdditionValues { // x y z System.out.println( "x=" + x + ", y=" + y + ", x+y=" + z ); SwapValues.java 2.11 SwapValues.java ( ) package section0208; public class SwapValues { public static void main(strings[] args) { int a = 2; int b = 3; // a b // System.out.println( "a=" + a + ", b=" + b ); int x = (1+2)*(3+4); double y = ((1+2)*(3+4))/(2.0*5); 2 (1+2)*(3+4) (1+2)*(3+4)/(2.0*5) (1+2)*(3+4)/2.0* Java ( ) ( )

42 28 2 Java I System.out.println( "x=" + x + ", y=" + y + ", x+y=" + z ); + + " " + " " " " " " + 10 " 10" System.out.println( " " ); double x 1.5 int y 2 (System.out.println) x = 1.5, y = int a b a=10, b= = AdditionValues2.java ( ) package section0209; public class AdditionValues2 { int a = 12; int b = 34; System.out.println( /* */ ); = 46 b = -10 if = -10

43 int x 1 Java x = x + 1; ( ) = x 1 x x 1 x + 1; x x 2 x = x + x; OK x y x = x + y; x y 1 x,y = x,y + 1; x = x + 1; y = y + 1; x 2 3 Java x x x += 2; x -= 2; x *= 2; x /= 2; x %= 2; ( ) + = x += 2; x = x + 2; x =+ 2; x = +2; (2 ) x y (a ) 2.13 CompoundAssignment.java ( )

44 30 2 Java I package section0210; public class CompoundAssignment { public static void main(string[] arge) { int a = 0; a += 7; System.out.println( "a = " + a ); a -= 2; System.out.println( "a = " + a ); a *= 5; System.out.println( "a = " + a ); a /= 3; System.out.println( "a = " + a ); a %= 3; System.out.println( "a = " + a ); a /= 3 (int ) x package section0210; public class ErrorSubst { int a; a += 5; System.out.println( "a = " + a ); ErrorSubst.java ( ) Eclipse ( ) a 3 5 int a = 0; 5 (Java )

45 ± x 1 x++; ++x; x 1 x--; --x; x ++; ( ) ++ (increment operator symbol) -- (decrement operator symbol) = ( x++;) x 1 ( x x++; x++; ) C C C ( ) C# C ++ (++ ) x 1 4 ( 2 ) x 2 2 x = x + 2; x++++; x++ x = x + 1 x++++; (x = x + 1)++; x = x + 2; x += 2; x y 1 z z = (x + y)++; (x + y)++ (x + y) = (x + y) + 1 z = x + y + 1; ( ) ++x x x; x++; x 1 int y = ++x + 3; int y = x++ + 3; int y = ++x + 3; int y = (x = x + 1) + 3; x = x x 3 y 2.15 package section0210; public class SubstInEquation { SubstInEquation.java ( )

46 32 2 Java I int x = 10; int y = ( x = x + 1 ) + 3; System.out.println( "x = " + x ); System.out.println( "y = " + y ); ( x = x + 1 ) ++x x++ y ++x x = x + 1 x++ y 1 ( 1 ) (int y = (++x) + 3;) x = x + 1; int y = x + 3; x=11, y=14 (int y = (x++) + 3;) int y = x + 3; x = x + 1; x=11, y=13 ( ) (++x; int y = x + 3; ) SubstInEquation2.java ( ) package section0210; public class SubstInEquation2 { int x = 1; int y = ( ++x ) + ( x++ ); System.out.println( "x = " + x + ", y = " + y ); Java (multiple assignment statement) 2.17 package section0210; public class MultipleSubst { int a; int b; int c; MultipleSubst.java ( )

47 c = b = a = 1; System.out.println( "a=" + a + ", b=" + b + ", c=" + c ); c = b = a = 1; a 1 b = (a = 1) b 1 c = (b = 1) c 1 (^^;) 2.18 MultipleSubst2.java ( ) package section0210; public class MultipleSubst2 { int a = 1; int b = 1; int c = 1; System.out.println( "a=" + a + ", b=" + b + ", c=" + c ); c = b*2 = a = 1; c = b++ = a = 1; MultipleSubst3.java ( ) package section0210; public class MultipleSubst3 { int x = 2; int y = 3; int z = 4; z += y *= x; System.out.println( "x=" + x + ", y=" + y + ", z=" + z ); 2.11 ( ) ( ) int double (double x = 2;) (int y = 2.0;) double int (cast) 2.0 y int y = (int) 2.0; y 2

48 34 2 Java I int y = (int) ; (int) 2.0 int y = ; double 3.0 int int y = (int)( ); 2 ( y 3 ) double x int y y = (int) x; x 1.5 y y int x = (int) 2.5-1; 2. int x = ; 3. float x = (float) ; 4. int x = (int) 12345L; 5. long x = (long) 123; 6. double x = (double) 12.3F; 7. byte x = (byte) 100; 8. long x = (long) 1234; 9. char x = (char) 12354; 10. int x = (int) true; 11. int x = (int) 'A'; 7 int short, byte int short, byte byte x = 100; 100 byte [ 128, 127] OK int a = 100; int a = 100; byte x = a; byte x = (byte) a; a 100 byte x = 200; byte x = (byte) a; 200 [ 128, 127] 2.20 package section0211; public class Casting1 { public static void main(string[] arge) { byte x = (byte) 200; System.out.println( "x = " + x ); Casting1.java ( ) 200 int Java 32bits byte x 8bits (byte) 32bits 8bits 24bits ) x 56 byte x = 100; 2.11 Java

49 bits 符号付き整数の キャスト (byte) 8bits 符号付き整数 -56 (2 の補数表現に注意 ) byte byte [ 128, 127] (byte) (x ) 1. byte x = (byte) -129; 2. byte x = (byte) -128; 3. byte x = (byte) 127; 4. byte x = (byte) 128; 2.21 package section0211; public class Casting2 { public static void main(string[] arge) { double x = 10.1; int y = (int)( x / 0.1 ); System.out.println( "y = " + y ); Casting2.java ( ) y = 101 y = System.out.println( x / 0.1 ); int x y ( ) Math.round() x = 2 int x double CompoundAssign.java ( )

50 36 2 Java I package section0211; public class CompoundAssign { public static void main(string[] arge) { int x = 0; x += 2.5; System.out.println( "x = " + x ); x += 2.5; x = x + 2.5; x = (int)( x ); ( ) a 1. double a = / 2 + 2; 2. double a = / 2 + 2; 3. double a = (4 + 3) / 2 + 2; 4. double a = (double) / 2 + 2; 5. double a = (double)(4 + 3) / 2 + 2; 6. double a = / ( ); (comparison operator) ( (relational operator) ) 2 2 boolean ( true false) 6 true ( ) 2 int double OK 2 == 2 1 = 1 (1 1 )

51 A == B A B 1 == 1 A!= B A B 1!= 2 A > B A B 2 > 1 A >= B A B 2 >= 1 A < B A B 1 < 2 A <= B A B 1 <= true false == <= > % 3!= == 1 / 'B' == 'A' (2 <= 3)!= true boolean true false A && B A & B 2 A B true true A B A B A B true true!a A false true A ^ B A B true A B A && B A B!A A ^ B true true true true false false true false false true false true false true false true true true false false false false true false int x 1 true false 1. x <= < x && x <=5 3. (x % 2 == 0) (x % 2 == 1) 4.!(x > 2) 5. (x - 0.1) / 7 == (x % 2 == 0)^(x % 2 == 1)

52 38 2 Java I 2 0 < x <= 5 ( ) (0 < x) <= 5 true <= 5 2 A && B A & B (short-circuit evalution) A && B A false B true false false ( ) B A B A true B true false true B A & B A B A B A && B A B A && B A B B A A false B a!= 0 && b / a > c) A & B A B ) ( methoda() & methodb()) Java 1. x 5 true 2. x true x true x y 5 true int year true

53 (Exclusive OR) ( ) 2 true Java ( = ) A ^ B = (A &&!B) (!A && B) = (A B) && (!A!B) A && B =!(!A!B), A B =!(!A &&!B) if (brunch) true A false B Java if x 0 y 1 0 y package section0212; public class IfElse { int x = 3; int y = 0; if( x >= 0 ) { y += 1; else { y -= 1; System.out.println( "y = " + y ); if if( ) { // true else { // false IfElse.java (if else ) if true if ( ) true else else ( ) else

54 40 2 Java I false if boolean boolean x if( x > 1000 ) OK if( x ) int x x x 2.24 package section0212; public class OddOrEven { int x = 100; // OddOrEven.java ( ) else else else if if( ) { // true false if if if ( if ) if if if 2 3 if x if( ) { if( ) { // true true else { // true false else { if( ) { // false true else { // false false

55 else int x y 4 x y int x x x x if( x > 0 ) { System.out.println( "x " ); if( x == 0 ) { System.out.println( "x " ); if( x < 0 ) { System.out.println( "x " ); x=1 2 3 true true int vote Vote.java 2.25 package section0212; public class Vote { int vote = 1; // Vote.java ( ) int vote = 1; if( vote == 1 ) {

56 42 2 Java I System.out.println( " " ); if( vote == 2 ) { System.out.println( " " ); if( vote == 3 ) { System.out.println( " " ); else { System.out.println( " " ); vote == 1 2 if vote == 3 else if( x > 0 ) { if( y > 0 ) { // x 0 y 0 else { // x 0 y 0 else { if( y > 0 ) { // x 0 y 0 else { // x 0 y 0 Java else if ( 1 ) if( x > 0 ) { if( y > 0 ) { // x 0 y 0 else { // x 0 y 0 else if( y > 0 ) { // x 0 y 0 else { // x 0 y 0 int x = 123; if( x == 2 ) { // x 2 else if( x % 2 == 0 ) { // x 2 else if( x > 2 ) { // x 2 (x = 123 ) else {

57 // x 0 else int degree S A B C D RankEvaluation.java S 90 A 80 B 70 C 60 D RankEvaluation.java ( ) package section0212; public class RankEvaluation { int degree = 85; // if A if( degree >= 90 ) { Systerm.out.println( " S " ); else if( degree < 90 && degree >= 80 ) { Systerm.out.println( " A " ); else if( degree < 80 && degree >= 70 ) { // : // ( ) if false degree < 90 degree < 90 ( ) degree >= 70 RankEvaluation2.java 2 RankEvalution RankEvalution2 ( )

58 44 2 Java I if ( ) if condition_a condition_b boolean if( condition_a && condition_b ) { System.out.println( true ); else { System.out.println( false ); if else 1 if( ) { // else { // if( ) // else // int x 0 x 2 2 // if( x >= 0 ) x *= 2; else x *= -2; if else // if( x >= 0 ) x *= 2; else x *= -2; int x = 1; int y = 2; if( x >= 0 ) x *= 2; y += 2;

59 y += 2; x >= 0 y +=2 x int x = 1; int y = 2; if( x >= 0 ) x *= 2; y += 2; 1 int x = 1; int y = 2; if( x >= 0 ) { x *= 2; y += 2; switch 1 switch switch if boolean case case defult int x = 123; switch( x % 3 ) { case 0: // x 3 break; case 1: // x 3 break; default: // 2 ( 3 2 ) break; char rank switch switch( rank ) { case 'S': System.out.println( " S " ); break; case 'A': System.out.println( " A " ); break; case 'B': System.out.println( " B " ); break;

60 46 2 Java I case 'C': System.out.println( " C " ); break; default: System.out.println( " " ); break; break; case switch rank == 'S' S break switch default case break; default switch switch if switch if ( ) drink switch drink == "orange" drink == "apple" drink == "coffee" drink == "tea" switch 'S' 'B' case rank rank == 'S' case 'S': break; case 'A': case 'B': case 'C': " " break; switch rank == 'A' rank == 'B' case 'C': break; switch ( rank=='d' ) defalut " " break; switch( rank ) { case 'S': case 'A': case 'B': case 'C': System.out.println( " " ); break;

61 default: System.out.println( " " ); a b x if if( a > b ) { x = a; else { x = b; if( a > b ) x = a; else x = b;?: x = ( a > b )? a : b;? true? false : a > b ( x = a > b? a : b; ) x = ( a > b? a : b ); degree 60 ( ) System.out.println( " " + (degree >= 60? " " : " ") + " " ); boolean ismale true false boolean if boolean

62 48 2 Java I 2.27 IsVariable.java (boolean ) package section0212; public class IsVariable { boolean ismale = true; // true false if( ismale == true ) { System.out.println( " " ); else { System.out.println( " " ); ismale ismale == true is ismale true false ismale == true true false if( ismale == true ) if( ismale ) boolean is is+ can+ has+ if( ismale ) ( ismale )? " " : " " for 10 for for(int i = 1; i <= 10; i++) { // for ( ) for 3 ( i++ ) for( ; ; )

63 i, j, k, l, m, n counter 1 ( 1 ) i++ i+=1 i=i+1 ++i OK ( i++ ) x for for for for ( 1 ) for ( 0 ) for 1. for(int i=0; i<10; i++) 2. for(int i=10; i>0; i--) 3. for(int k=1; k<=100; k+=2) 4. for(int j=1; j<100; j*=2) 5. for(int i=1; i>-100 && i<100; i*=-2) 6. for(char c='a'; c<='z'; c++) 7. for(double x=-1.0; x<=1.0; x+=1.0/50) double 2.28 DoubleCounter.java ( )

64 50 2 Java I package section0213; public class DoubleCounter { int count = 0; for(double x=-1.0; x<=1.0; x+=1.0/50) { System.out.println( count + ":" + x ); count++; count 1.0/ x==1.0 1 (1.0 ) for for while int n '*' PrintStar.java for for n n-1 1 PrintStar2.java 2 for i n 1 for 1 i ********** ********* *** ** * package section0213; public class FibonacciNumbers { int a = 1; int b = 1; System.out.print( a + " " + b + " " ); for(int i=3; i<=10; i++) { int c = a + b; System.out.print( c + " " ); a = b; b = c; FibonacciNumbers.java ( )

65 System.out.println(); n 3 1 n 2, 3, 5 NoMultiple2.java 2.30 NoMultiple.java (3 ) package section0213; public class NoMultiple { int n = 100; System.out.println( "1 " + n + " " ); for(int i=1; i<=n; i++) { if( i % 3!= 0 ) { System.out.println( "3 " + i ); n 2, 3, NoMultiple3.java while 2 while while for for while 10 while int i = 1; while( i <= 10 ) { // i++; for 3

66 52 2 Java I while Java int long n CollatzSequence.java Collatz n 1 n n 2 n CollatzSequence.java ( ) package section0213; public class CollatzSequence { int n = 7; System.out.print( "n = " + n ); // " " // n == 1 // // do while 1 do while 10 do while int i = 1; do { // i++; while( i <= 10 ); for 3 do while while do while 2 2

67 i <= 10 while do while 2.32 package section0213; public class WhileVSDoWhile { int count = 0; while( count > 0 ) { System.out.println( "while " ); do { System.out.println( "do while " ); while( count > 0 ); WhileVSDoWhile.java (while do while ) do while FibonacciNumbers.java 3 a, b, c System.out.println( "a="+a+", b="+b+", c="+c ); c 2.33 FibonacciNumbers.java ( ) package section0213; public class FibonacciNumbers { int a = 1; int b = 1; System.out.print( a + " " + b + " " ); for(int i=3; i<=10; i++) { int c = a + b; System.out.print( c + " " ); a = b; b = c; System.out.println(); System.out.println( "a="+a+", b="+b+", c="+c );

68 54 2 Java I if a b main ( ) c 8 for ( ) 14 3 a, b 2 c c 1 i i for i 7 12 for ( ) 14 i 4 int a = 1; ( {int a = 1; ) a 2 int i; for(i=1; i<=10; i++) { System.out.println( "i=" + i ); for(i=1; i<=20; i+=2) { System.out.println( "i=" + i ); 2 for main Java CPU 2 i CPU CPU for(int i=1; i<=10; i++) { System.out.println( "i=" + i ); for(int i=1; i<=20; i+=2) { System.out.println( "i=" + i ); while do while

69 int i = 1; while( i <= 10 ) { System.out.println( i ); i++; for(int i=1; i<=10; i++) { System.out.println( i ); for... for (i=1; i<=10; i++) while { int i = 1; while( i <= 10 ) { System.out.println( i ); i++; for(int i=1; i<=10; i++) { System.out.println( i ); while i for while do while ( ) 2.34 package section0213; public class InfiniteLoop { int i = 10; // int i = -1; while( i!= 0 ) { System.out.println( "i=" + i ); i--; InfiniteLoop.java ( )

70 56 2 Java I 10 1 i 0 4 i 1 ( ) Eclipse ( ) (^^;) for(int i=0; i<=10; i--) // i++ int i=0; while( i < 10 ) { System.out.println( i ); // i++ ( ) 10 while( true ) 20 break; 2.35 GuessingGame.java ( ) package section0213; import java.util.scanner; public class GuessingGame { Scanner scan = new Scanner(System.in); System.out.println( " " ); System.out.println( " 1 99 " ); int value = (int)( 1 + Math.random()*99 ); int count = 0; while( true ) { count++; System.out.print( " Enter!" ); int n = scan.nextint(); if( n < value ) { System.out.println( " " ); else if( n > value ) { System.out.println( " " ); else { System.out.println( " "); break; System.out.println( " " + count + " "); scan.close();

71 while( true ) boolean for for(;;) for 3 3 for(;;) break; switch break; for while do while switch FibonacciNumbers.java Fibonacci FibonacciNumbers2.java ( ) System.out.printf i j (i*j) System.out.println(); ( ) 2.36 package section0213; public class MultiplicationTable { System.out.print( " " ); for(int j=1; j<=9; j++) { System.out.printf( "%2d ",j ); System.out.println(); System.out.print( "---+" ); for(int j=1; j<=9; j++) { System.out.print( "---" ); System.out.println(); for(int i=1; i<=9; i++) { System.out.printf( "%2d ", i ); for(int j=1; j<=9; j++) { MultiplicationTable.java ( )

72 58 2 Java I System.out.printf( "%2d ", (i*j) ); System.out.println(); for(int i=0; i<5; i+=2){ for(int j=4; j>=0; j-=2){ System.out.println( i*j ); int i = 1; while( i < 5 ){ int j = 10; while( j > 4 ){ System.out.println( i*j ); j -= 2; i+=1; Fifteen.java Fifteen2.java % ( ) 2

73 money rate 10 ( CompoundInterest.java ) ( CompoundInterest2.java ) break continue break; break; continue; continue; for(int i=1; i<=100; i++) { if( i % 2 == 0 i % 5 == 0 ) continue; System.out.println( i ); if for continue; break; break; 2.37 DoubleLoop.java ( ) package section0213; public class DoubleLoop { for(int i=1; i<=3; i++) { System.out.println( "i=" + i +": "); for(int j=1; j<=3; j++) { System.out.println( " j=" + j + ": "); if( i == 2 && j == 2 ) break; break (^^;)

74 60 2 Java I 2.38 DoubleLoop2.java ( break ) package section0213; public class DoubleLoop2 { loop_i: for(int i=1; i<=3; i++) { System.out.println( "i=" + i +": "); for(int j=1; j<=3; j++) { System.out.println( " j=" + j + ": "); if( i == 2 && j == 2 ) break loop_i; i for ( loop_i) break break continue 2.39 DoubleLoop3.java ( continue ) package section0213; public class DoubleLoop3 { loop_i: for(int i=1; i<=3; i++) { System.out.println( "i=" + i +": "); for(int j=1; j<=3; j++) { System.out.println( " j=" + j + ": "); if( i == 2 && j == 2 ) continue loop_i; break i loop_i: for(int i=1; i<=3; i++) { for(int j=1; j<=3; j++) { if( i * j == 4 ) break loop_i; // i j 2

75 LoopParameter.java ( ) package section0213; public class LoopParameter { int ii = 0; int jj = 0; loop_i: for(int i=1; i<=3; i++) { for(int j=1; j<=3; j++) { if( i * j == 4 ) { ii = i; jj = j; break loop_i; System.out.println( " " + ii + " " + jj + " " ); int 1 x int int[] x; 1 y double[] y; ( ) int x[]; Java Java int[] a, b; // int int c[], d; // c int d int 1 1

76 62 2 Java I int[] x; JVM x 1 ( 2.13 ) x 1 5 x = new int[5]; new JVM ( ) ( int[5]: 5 ) [0] [1] [4] x [i] x[i] x[0] x ( x ) new x x ( ) int[] x = new int[5]; 1 x!"# int[] x;$x%#&'( 1)*+!"#$%&!"#$'()* [0] [1] [2] [3] [4]!"# new int[5]$%&'()*+,-./ int0512#)*345!"#$int[] x = new int[5];%&'()*'+%,-.$ /0%12 x[0]%34567 x#,-89:$;<=>?@a double x boolean check int[] x = new int[5]; ( (^^;)) new int[5]; 5 (int 0 ) double 0 boolean false 0 ( 2.13 ) [0] [1] [4] [1] [2]

77 [5] Java 0 5 [5] 5 x[0] = 2; x 2 x[1] = -1; x[2] = 3; x[3] = 0; x[4] = 5; ( 2.14 ) x [0] [1] [2] [3] [4] package section0214; public class ArrayInitialization { int[] x = new int[5]; x[0] = 2; x[1] = -1; x[2] = 3; x[3] = 0; x[4] = 5; ArrayInitialization.java ( ) Java 5 1 int[] x = {2, -1, 3, 0, 5; new int[5]; int int[] x = {2, -1, 3, 0, 5; int[] x; x = {1, 2, 3, 4, 5; // 2 (!?) (new int[5]{1, 2, 3, 4, 5; ) int[] x; x = new int[]{1, 2, 3, 4, 5; // 2

78 64 2 Java I new int[] ( ) i++; i = i + 1; double y package section0214; public class PrintArray { int[] degree = { 90, 85, 72, 100, 95 ; for(int i=0; i<degree.length; i++) { System.out.println( degree[i] ); PrintArray.java ( ) for 2 degree.length.length degree.length 5 degree[0] degree[4] 5 for(int i=0; i<=4; i++) degree.length for degree.length for for(int i=0; i<=degree.length-1; i++) Java for(int i=0; i<degree.length; i++) i int PrintArray.java ( ) 1 PrintArray2.java 2. PrintArray2.java PrintArray3.java ( )

79 Java degree System.out.println( Arrays.toString( degree ) ); import java.util.arrays; PrintArray4.java 10 { 1, 2, 3,..., 10 i ArrayInitialization2.java ( ) package section0214; import java.util.arrays; public class ArrayInitialization2 { int[] array = new int[10]; for(int i=0; i<array.length; i++) { array[i] = i + 1; System.out.println( "array = " + Arrays.toString( array ) ); a = {2, 4, 6, 8, 10,, a = {1, 2, 4, 8, 16, 32,, a = {1, 1, 1, 1, 1, 1,, 1 sum int int int sum = 0; int sum; sum += degree[i]; (int sum = 0;) int sum = 0; for(int i=0; i<degree.length; i++) { sum for(int i=0; i<degree.length; i++) { sum 2.44 package section0214; public class SumOfArray { int[] degree = { 90, 85, 72, 100, 95 ; SumOfArray.java ( )

80 66 2 Java I int sum = 0; for(int i=0; i<degree.length; i++) { // int sum = 0; sum += degree[i]; System.out.println( " " + sum ); max int max = 0; 2.45 package section0214; public class MaxOfArray { int[] degree = { 90, 85, 72, 100, 95 ; int max = 0; for(int i=0; i<degree.length; i++) { if( degree[i] > max ) { max = degree[i]; System.out.println( " " + max ); MaxOfArray.java ( ) max 1 max 0 max 2 1. Java int Integer.MIN_VALUE ( 2.5 IntegerMaxAndMin.java ) degree degree[0] max = degree[0]; 2. degree[0] 1. max = degree[0]; max = degree[0]; int i=1 1 0 ( ) degree

81 degree MinOfArray.java degree AverageOfArray.java x AverageOfPositive.java 2.46 AverageOfPositive.java ( ) package section0214; public class AverageOfPositive { int[] x = { 15, -30, -18, 0, 25, 32, -5, 16, 51 ; // x // // // OlympicGame.java OlympicGame.java ( ) package section0214; public class OlympicGame { double[] points = {9.95, 9.82, 9.95, 10.0, 9.64, 9.55, 10.0; // points // points 2 // // " "

82 68 2 Java I DifferenceTwoArray.java ( ) package section0214; import java.util.arrays; public class DifferenceTwoArray { int[] x = { 90, 85, 72, 100, 95 ; int[] y = { 82, 70, 98, 68, 70 ; int[] z = new int[x.length]; for(int i=0; i<z.length; i++) { z[i] = x[i] - y[i]; System.out.println( "x - y = " + Arrays.toString( z ) ); SwapArray.java 2.49 SwapArray.java ( ) package section0214; public class SwapArray { int[] a = {13, 53, 24, 67, 83, 40; int[] b = {20, 14, 61, 94, 92, 50; // // a[0] b[0],..., a[a.length-1] b[b.length-1] // System.out.println("a = " + Arrays.toString( a ) ); System.out.println("b = " + Arrays.toString( b ) );

83 a a[0] a[a.length 1] a[1] a[a.length 2] ToReverseOrder.java 2.50 ToReverseOrder.java ( ) package section0214; public class ToReverseOrder { int[] a = { 11, 19, 15, 17, 21, 13, 23, 27, 25 ; // // // int degree ( S, A, B, C, D ) int grade EvaluateGrade.java 2.51 EvaluateGrade.java ( ) package section0214; public class EvaluateGrade { int[] degree = {82, 90, 65, 30, 80, 66, 72, 59, 20, 90, 75, 84, 68, 75, 45, 76, 90, 98, 55, 42, 100, 92, 78, 85, 72, 45, 62, 70, 82, 95, 60, 38, 92, 85, 78, 55, 80, 74, 92, 83 ; // grade[0]: S... grade[4]: D int[] grade = { 0, 0, 0, 0, 0 ; String[] gradename = { "S", "A", "B", "C", "D" ; // degree // grade // 90 S grade[0] // for(int i=0; i<grade.length; i++ ) { System.out.println( " " + gradename[i] + " " + grade[i] + " " );

84 70 2 Java I n ShiftArray.java int[] array = { 1, 2, 3, 4, 5 ; int n = 2; array = { 4, 5, 1, 2, 3; ( %) 2.52 ShiftArray.java ( ) package section0214; import java.util.arrays; public class ShiftArray { int[] array = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ; int n = 5; // array n // System.out.println( Arrays.toString( array ) ); Java 2 3 A int[][] A = new int[2][3]; int[] x = new int[4]; int[][] A new int A ( A[0] ) A ( 2.15 ) A 2 A[0], A[1] A[0] 2 A[0][0] A[0][1] A[0][2] A 参照 参照参照 A[1][0] A[1][1] A[1][2] A[0] A[1] 2.15

85 A[0][0] = 3; A[0][1] = -2; A[0][2] = 5; A[1][0] = 0; A[1][1] = 4; A[1][2] = -1; ( 2.16 ) A[0][0] A[0][1] A[0][2] A A[0] A[1] A[1][0] A[1][1] A[1][2] package section0214; public class ArrayInitialization3 { // int[][] A = new int[2][3]; A[0][0] = 3; A[0][1] = -2; A[0][2] = 5; A[1][0] = 0; A[1][1] = 4; A[1][2] = -1; int[][] B = { { 3, -2, 5, { 0, 4, -1 ; ArrayInitialization3.java ( ) int[][] C; C = new int[][]{ { 3, -2, 5, { 0, 4, -1 ; Java 1 A int[][] A[0] A[0][0] A[0][0] int A[0] A[0][0] A[0][2] 1 int[] 12 A[0] = new int[] { 1, 2, 3 ; (A[0] A[0] = { 1, 2, 3 ;

86 72 2 Java I ) 3 1, 2, 3 A[0] A[0] { 3, -2, 5 { 1, 2, 3 { 3, -2, 5 (^^;) Java GC (Garbage Collection) GC Java 1 C ++ GC GC Java GC ( ) GC A ( 2 ) (1) (2) (3) (4) (5) (6) Java int 3 A int B {{{1,2,3,4,{5,6,7,8,{9,10,11,12,{{13,14,15,16,{17,18,19,20,{21,22,23, B Java A A[0] A[1]

87 A[0][0] A[0][1] A[0][2] A[0][3] A 参照 参照 A[0] A[1] 参照 A[1][0] A[1][1] 2.17 (int[][] A = new int[2][];) A[0] A[1] int[] 1 A[0] int[] A[0] 1 A[0] = new int[4]; A[0] 4 int[][] A = new int[2][]; A[0] = new int[4]; A[1] = new int[2]; A[0][0] = 1; : A[1][1] = 5; // int[][] B = {{1, -2, 0, 3, {-3, 5; // int[][] C; C = new int[][]{{1, -2, 0, 3, {-3, 5; // int[][] D = new int[2][]; D[0] = new int[]{1, -2, 0, 3; D[1] = new int[]{-3, 5; int A StudentDegrees.java 2.54 package section0214; public class StudentDegrees { int[] sno = {1401, 1402, 1403; int[][] degrees = { {80, 95, 65, 70, {100, 55, 82, 78, 90, {95, 85, 72; StudentDegrees.java ( )

88 74 2 Java I // int SetArrays.java x [0] [1] [2] [3] [4] [5] y z [0] [1] [2] [3] [4] [0] [1] [2] [0] [1] [2] [0] [1] [2] [3] [4] [0] [1] package section0214; public class SetArrays { // x, y, z // x y z // SetArrays.java ( ) //, x 1, 2, 3, 4, 5 // for x[0]=1, x[1]=2,... // //, y int sum, // System.out.println( " y " + sum + " " ); //, z -1

89 null ArrayIndexOutOfBoundsException package section0214; public class ArrayIndexOutOfBounds { int[] array = { 1, 2, 3, 4, 5 ; System.out.println( array[5] ); ArrayIndexOutOfBounds.java ( ) 0 int[] x = new int[0]; int[] y = { ; int[] x = null; 0 ( ) null int x int y null ( 0 ) 2.57 package section0214; import java.util.arrays; public class ArrayCopy { int[] x = { 1, 3, 0, -2, 4 ; ArrayCopy.java ( )

90 76 2 Java I int[] y = new int[x.length]; for(int i=0; i<x.length; i++) { y[i] = x[i]; // y System.out.println( "y = " + Arrays.toString( y ) ); x y int[] y = new int[x.length]; x.length y for 1 (^^;) 2.58 ArrayCopy2.java ( ) package section0214; import java.util.arrays; public class ArrayCopy2 { int[] x = { 1, 3, 0, -2, 4 ; int[] y = x; System.out.println( "y = " + Arrays.toString( y ) ); int[] y = x; x OK int[] y = x; x[0] = -1; y y y[0] -1 int[] y = x; ( 2.18 ) x 5 x[0] int[] y = x; y x[0] y x x[0] = -1; y[0] -1 x 参照 [0] [1] [2] [3] [4] コピー y 参照 代入 ArrayCopy3.java

91 ArrayCopy3.java ( ) package section0214; public class ArrayCopy3 { int[][] A = { {1, 3, 0, {-2, 4 ; // A int B // A // 2 1 OK for Java for Java 5 10 Java 9 for C ++ for-each 1 for 1 [0] for 2.60 package section0214; public class ExtendedForEach { int[] x = { 1, 3, 0, -2, 4 ; for(int xi : x) { System.out.print( xi + " " ); System.out.println(); ExtendedForEach.java ( for ) for ( ) x int int x xi x x xi xi 1 xi ( )

92 78 2 Java I double y ExtendedForEach2.java for 2.61 ExtendedForEach2.java ( for ) package section0214; public class ExtendedForEach2 { double[] y = { 12.34, 35.79, , 20.52, ; // for y sum System.out.println( " " + sum ); ExtendedForEach3.java 2.62 ExtendedForEach3.java ( for ) package section0214; public class ExtendedForEach3 { int[][] A = { {1, 3, 0, {-2, 4 ; // for A for for ( for OK ) MatrixVector.java ( ) package section0214; public class MatrixVector { int[][] A = {{1,2,3,{1,1,1,{0,1,-1; int[] x = {1,1,1; // System.out.println( "A=" ); for(int i=0; i<a.length; i++) { for(int j=0; j<a[i].length; j++) { System.out.printf( "%3d", A[i][j] );

93 System.out.println(); System.out.println(); // System.out.println( "x=" ); for(int i=0; i<x.length; i++) { System.out.printf( "%3d%n", x[i] ); System.out.println(); // int[] y = new int[a.length]; for(int i=0; i<a.length; i++) { y[i] = 0; for(int j=0; j<a[i].length; j++) { y[i] += A[i][j] * x[j]; // System.out.println( "Ax=" ); for(int i=0; i<x.length; i++) { System.out.printf( "%3d%n", y[i] ); System.out.println(); java.util.arrays.deeptostring() 2.64 MatrixMatrix.java ( ) package section0214; import java.util.arrays; public class MatrixMatrix { int[][] A = {{1,2,3,{1,1,1,{0,1,-1; int[][] B = {{1,0,1,{0,1,1,{1,1,0; // System.out.println( " A = " + Arrays.deepToString( A ) ); System.out.println( " B = " + Arrays.deepToString( B ) ); // int[][] C = new int[a.length][b[0].length]; for(int i=0; i<c.length; i++) { for(int j=0; j<c[i].length; j++) { C[i][j] = 0; for(int k=0; k<b.length; k++) { C[i][j] += A[i][k] * B[k][j]; // System.out.println( "AB = " + Arrays.deepToString( C ) );

94 80 2 Java I 2.15 Math Math Math ( ) (B.6.3 ) 2.65 TrigonometricTable.java ( ) package section0215; public class TrigonometricTable { int sep = 12; for(int k = 0; k<=sep; k++) { double theta = Math.PI * k / sep; double costheta = Math.cos(theta); double sintheta = Math.sin(theta); System.out.println( " =" + k + " /" + sep + ", cos =" + costheta + ", sin =" + sintheta ); Math.PI Java 3.14 Math 1 ( e = ) Math.E (^^;) 2.66 MathMethods.java ( ) package section0215; public class MathMethods { double a = ; System.out.println( a + " " + Math.abs(a) ); double x = 100; System.out.println( "log_e(" + x + ") " + Math.log(x) ); System.out.println( "log_10(" + x + ") " + Math.log10(x) ); int p = 3; System.out.println( "e^" + p + " " + Math.pow(Math.E,p) ); System.out.println( " " + p + " " + Math.sqrt(p) ); int m = 5; int n = 3; System.out.println( "max(" + m + "," + n + ") " + Math.max(m,n) ); System.out.println( "min(" + m + "," + n + ") " + Math.min(m,n) );

95 2.15 Math Math ( ) int abs(int) double abs(double) double cos(double) radian cos double sin(double) radian sin double tan(double) radian tan double log(double) ( e) double log10(double) ( 10) double pow(double, double) x y pow(x, y) int max(int, int) double max(double, double) 2 int min(int, int) double min(double, double) 2 double sqrt(double) double random() [0, 1) long round(double) int round(float) System.out.println( "[0,1) 2 " + Math.random() + "," + Math.random()); System.out.println( a + " " + (int)(math.round(a))); static void mein(string args) System.out.Println( ' ' + r + ' ' + area ); pakage section0215; double r = 1.5; pablic class CircleArea { double area = r * r * Math.PAI; ABC AB AC a, b 2 θ ABC (1/2)ab sin θ theta 30 Math.sin(double)

96 82 2 Java I 2.67 package section0215; public class TriangulumArea { double a = 1.0; double b = 1.0; double theta = 30.0; // TriangulumArea.java ( ) double area = System.out.println( " " + area ); Math.random() 1 6 Dice.java Dice2.java Math.random() ( ) Math.random() Java (Mersenne twister) SFMT Math.random() Math.random()

97 Scanner System.in System.out System.out.println() print() Math.cos() Math System Math System GC (Garbage Collection) System Math PI in out 2 (PI ) Math.PI System.in System.out System.out.println() System.out println() System.out System.out.println() System.in System.in (^^;) Scanner Scanner(System.in) System Math Scanner Java Java Scanner import 1 2 import Scanner java.util.scanner Eclipse Scanner java.util.scanner import import 1

98 84 2 Java I 2.68 package section0216; import java.util.scanner; public class OddEven { Scanner scan = new Scanner( System.in ); System.out.print( " " ); int n = scan.nextint(); scan.close(); if( n % 2 == 0 ) { System.out.println( n + " " ); else { System.out.println( n + " " ); OddEven.java ( ) 5 System.in Scanner Scanner scan Scanner 1 scan scan OK scan scan 1 nextint() int 1 7 n 6 6 print 1 nextint() Scanner ( close() ) Eclipse Eclipse Eclipse n 8 (scan.close()) 2 ax 2 + bx + c = 0 3 nextdouble() ax 2 + bx + c 3 (a 0 ) d = b 2 4ac d < 0 d > 0 2 x1 = + ( b+ d)/(2a) x2 = + ( b d)/(2a)

99 2.17 II 85 Math.sqrt() d == 0 x= + (-b)/(2a) 2.69 QuadraticEquation.java ( ) package section0216; import java.util.scanner; public class QuadraticEquation { Scanner scan = new Scanner( System.in ); System.out.println("ax^2+bx+c "); System.out.print( "a = " ); double a = scan.nextdouble(); System.out.print( "b = " ); double b = scan.nextdouble(); System.out.print( "c = " ); double c = scan.nextdouble(); scan.close(); // a, b, c // Scanner 2.17 II 2 System.out.print() System.out.println() ( ) System.out.printf() C System.out.printf() System.out printf() package section0217; public class TrigonometricTable2 { TrigonometricTable2.java (printf )

100 86 2 Java I int sep = 12; for(int k = 0; k<=sep; k++) { double theta = Math.PI * k / sep; double costheta = Math.cos(theta); double sintheta = Math.sin(theta); System.out.printf( " =%02d /%2d, cos =%9.6f, sin =%9.6f%n", k, sep, costheta, sintheta ); printf() 1 " =%02d /%2d, cos =%9.6f, sin =%9.6f%n" % %kd k (%2d) 0 0 (%02d) %k.mf k m (%9.6f) k %n printf() (print() ) %n %02d %2d %9.6f %9.6f k sep costheta sintheta ( ) %b, %B boolean %c, %C char %e, %E %o 8 %s, %S %x, %X 16 %E Newton 2.71 NewtonMethod.java ( Newton ) package section0217; public class NewtonMethod { // f(x) = cos(1/log x) = 0 x 1.2 Newton // f'(x) = sin(1/log x)/(x(log x)^2) int count = 0; double x = 1.6;

101 2.17 II 87 String format = "count=%d : x=%10.7f f(x)=%13.5e%n"; while( Math.abs(f(x)) > 1.0e-15 ) { System.out.printf( format, count, x, f(x) ); x = x - f( x )/df( x ); count++; System.out.printf( format, count, x, f(x) ); static double f(double x) { return Math.cos(1.0/Math.log( x )); static double df(double x) { return Math.sin(1.0/Math.log( x ))/(x*math.pow(math.log( x ),2)); 8 10, 14 printf() %10.7f 10 7 %13.5e Mathematica (! (^^;)) f[x_] := Cos[1/Log[x]]; Print["f(x)=", f[x]] Print["f'(x)=", D[f[x], x]] Plot[f[x], {x, 1, 3] NSolve[{f[x] == 0, x >= 1.2, x] 1 f(x)=cos Log[x] f'(x)= Sin 1 Log[x] xlog[x] {{x , {x Mathematica

102 88 2 Java I 2.18 I API (Application Programming Interface) 1 main main main main 1 Java API (Application Programming Interface : 200 3, 500 ) Math.cos() java.lang.math 1 main main CircleArea.java (main ) package section0218; public class CircleArea { for(int r=1; r<=10; r++) { double area = r * r * Math.PI; System.out.printf( " =%2d %8.4f %n", r, area ); 2.73 CircleArea2.java ( ) package section0218; public class CircleArea2 { for(int r=1; r<=10; r++) { printcirclearea( r ); // radius area static void printcirclearea( int r ) { double area = r * r * Math.PI; System.out.printf( " =%2d %8.4f %n", r, area );

103 2.18 I CircleArea.java main CircleArea2.java main printcirclearea main printcirclearea (main printcirclearea ) main main main static main (static ) static ( ) static public ( ) public main public printcirclearea printcirclearea section0218 ( ) Java double x = Math.cos(Math.PI/4); cos π/ ( ) x printcirclearea void void Java main void main String args printcirclearea int radius main String[] args ( ) y = f(x) x f y f(x) 2.74 package section0218; public class CircleArea3 { for(int r=1; r<=10; r++) { printcirclearea( r ); // CircleArea3 ( )

104 90 2 Java I static void printcirclearea( int r ) { double area = circlearea( r ); System.out.printf( " =%2d %8.4f %n", r, area ); // radius static double circlearea( double radius ) { double area = radius * radius * Math.PI; return area; circlearea void double circlearea() printcirclearea circlearea area circlearea ( printcirclearea()) return area; return void printcirclearea return (return void ) CircleArea3 CircleArea2 circlearea() printcirclearea() circlearea() ( ) double int circlearea double // radius static double circlearea( int radius ) { System.out.println( " " ); double area = radius * radius * Math.PI; return area; circlearea Java main r

105 2.18 I 91 circlearea (int ) double method(int a, int b) double method(int x, int y) 2. double method(int a, int b) int method(int a, int b) 3. double method(int a, double b) double method(double a, int b) 4. double method(int a, int b) double method(int a) 5. double method(int a, int b) double method(double x, double y) 6. double method(int a, int b) void method(int a, int b) method( 1, 2 ); printcirclearea() circlearea() r circlearea() radius 2 circlearea() r radius printcirclearea() circlearea() r 1 circlearea() radius ( 2.20 ) int r 1 代入 printcirclearea( ) メソッド側 double area = circlearea( r ); circlearea( ) メソッド側コピー static double circlearea( double radius ){ return area; 値を戻す 2.20

106 92 2 Java I A B double max(double, double) B 2 A A B void swap(int, int) B SwapValues.java 2.75 SwapValues2.java ( ) package section0218; public class SwapValues2 { int a = 1; int b = 2; swap( a, b ); System.out.println( " " + a ); System.out.println( " " + b ); static void swap( int x, int y ) { // x >= y x < y if( x < y ) { int temp = x; x = y; y = temp; int a int b 1 2 代入 代入 main メソッド側 swap メソッド側 swap( a, b ); コピーコピー static void swap( int x, int y ){ 交換しても main に戻していない (^^)b

107 2.18 I 93 ( 2.21 ) Java positivearray() 2.76 FormalParameter.java ( ) package section0218; import java.util.arrays; public class FormalParameter { int[] array = { 1, -2, -3, 4, -5 ; positivearray( array ); // printarray( "array", array ); // static void positivearray( int[] x ) { for(int i=0; i<x.length; i++) { x[i] = Math.abs( x[i] ); static void printarray( String name, int[] x ) { System.out.println( name + " = " + Arrays.toString( x ) ); array 5 5 postitivearray() main void main array ( ) ( ) positivearray static void positivearray( int[] x ) { x = new int[]{ 1, 1, 1, 1, 1 ; 1 1 x main main array { 1, -2, -3, 4, ( ) main

108 94 2 Java I 2.77 package section0218; import java.util.arrays; public class LinearAlgebra { int[][] A = {{1,2,3,{1,1,1,{0,1,-1; printm( "A", A ); int[] x = {1,1,1; printv( "x", x ); // y = Ax int[] y = prodmv( A, x ); printv( "Ax", y ); int[][] B = {{1,0,1,{0,1,1,{1,1,0; printm( "B", B ); LinearAlgebra.java ( ) // C = AB int[][] C = prodmm( A, B ); printm( "AB", C ); // static void printm( String name, int[][] A ) { System.out.println( name + " = " + Arrays.deepToString( A ) ); // static void printv( String name, int[] x ) { System.out.println( name + " = " + Arrays.toString( x ) ); // static int[] prodmv( int[][] A, int[] x ) { int[] y = new int[a.length]; for(int i=0; i<a.length; i++) { y[i] = 0; for(int j=0; j<a[i].length; j++) { y[i] += A[i][j] * x[j]; return y; // static int[][] prodmm( int[][] A, int[][] B ) { int[][] C = new int[a.length][b[0].length]; for(int i=0; i<c.length; i++) { for(int j=0; j<c[i].length; j++) { C[i][j] = 0; for(int k=0; k<b.length; k++) { C[i][j] += A[i][k] * B[k][j];

109 2.18 I 95 return C; main A 2 static int[][] transmnew( int[][] A ) static void transmself( int[][] A ) A main x static double lengthv( int[] x ) Ã n x = x 2 i, (n = x ) i=1 double length = lengthv( {1, 2, 3, 4, 5 ); double length = lengthv( new int[]{1, 2, 3, 4, 5 ); // static int[] toarray( int x, int y ) { return {x, y; return new int[]{x, y; (recurrence relation) 2.78 FibonacciRecursive.java ( ) package section0218; public class FibonacciRecursive { int n = 10; System.out.println( "Fibonacci " + n + " " + fibo( n ) );

110 96 2 Java I static int fibo( int n ) { if( n == 1 n == 2 ) return 1; else return fibo( n-1 ) + fibo( n-2 ); n F n F n = F n 1 + F n 2, F 1 = F 2 = 1 n fibo n (return 1;) n > 2 fibo n 1 n 2 main FactorialRecursive.java ( ) package section0218; public class FactorialRecursive { int n = 10; System.out.println( n + "! " + fact( n ) ); static int fact( int n ) { if( n == 1 ) return 1; else return n * fact( n-1 ); 10 10! = n! = n (n 1)!, 1! = 1 (recursive program) (Tower of Hanoi) package section0218; public class HanoiTower { int n = 3; // hanoi( n, 'A', 'B', 'C' ); HanoiTower.java ( )

111 2.18 I 97 static void hanoi( int n, char a, char b, char c ) { if( n == 0 ) return; hanoi( n-1, a, c, b ); System.out.println( n + " " + a + " " + b + " " ); hanoi( n-1, c, b, a ); hanoi hanoi n 2 ( a ) 3 ( b ) 4 ( c ) A B C A B C 2.22 (1) 2.23 (2) n n hanoi hanoi( n-1, 'A', 'C', 'B' ) 1 hanoi( n-1, 'C', 'B', 'A' ) n n n 1 n 2 hanoi n 0 hanoi( 0, a, b, c ) 9 hanoi void return return void return 1 return return hanoi 9 return 1 12 return return

112 98 2 Java I return return if 5 static void method( int a ) { if( a < 0 ) // 2 System.out.println( " return" ); return; System.out.println( " " ); n = 3 hanoi A B C A A B n HanoiTower2.java 2. A C n HanoiTower3.java 3. A, B, C, D A B n HanoiProblem4.java main main static main(string[] args) null args 2.81 package section0218; public class MainParameters { int a = Integer.valueOf( args[0] ); int b = Integer.valueOf( args[1] ); MainParameters.java ( )

113 2.18 I 99 System.out.println( a + " + " + b + " = " + (a + b) ); ( ) (N) ( 2.24 ) 2.25 (x) = ( 2.26 ) (A) main main String[] args args[0] = "12" args[1] = "34" main Integer Integer.valuesOf() int C main main 1 int main(void) int main(int args, char *argv[]) 2 int System.arraycopy?? 2.82 package section0214; import java.util.arrays; public class ArrayCopy { int[] x = { 1, 3, 0, -2, 4 ; int[] y = new int[x.length]; for(int i=0; i<x.length; i++) { ArrayCopy.java ( )

114 100 2 Java I y[i] = x[i]; // y System.out.println( "y = " + Arrays.toString( y ) ); 2.83 ArrayCopyExample1.java ( ) package section0218; import java.util.arrays; public class ArrayCopyExample1 { int[] x = { 1, 3, 0, -2, 4 ; int[] y = new int[x.length]; System.arraycopy(x, 0, y, 0, x.length); // y System.out.println( "y = " + Arrays.toString( y ) ); System arraycopy arraycopy(a1,s1,a2,s2,len) a1 [s1] a2 [s2] len len 0 len ArrayIndexOutOfBound ArrayCopy3.java ( ) package section0214; import java.util.arrays; public class ArrayCopy3 { int[][] A = { {1, 3, 0, {-2, 4 ; int[][] B = new int[2][]; for(int i=0; i<a.length; i++) { B[i] = new int[a[i].length]; for(int j=0; j<a[i].length; j++) { B[i][j] = A[i][j]; System.out.println( "B = " + Arrays.deepToString( B ) ); 2.85 ArrayCopyExample2.java ( )

115 2.18 I 101 package section0218; import java.util.arrays; public class ArrayCopyExample2 { int[][] A = { {1, 3, 0, {-2, 4 ; int[][] B = new int[2][]; System.arraycopy(A, 0, B, 0, A.length); A[0][0] = 0; // System.out.println( "B = " + Arrays.deepToString( B ) ); B[0][0] 0 (Shallow copy) (Deep copy) Arrays.toString() Arrays.deepToString() 2.86 ArrayCopyExample3.java ( ) package section0218; import java.util.arrays; public class ArrayCopyExample3 { int[][] A = { {1, 3, 0, {-2, 4 ; int[][] B = new int[2][]; for(int i=0; i<a.length; i++) { B[i] = new int[a[i].length]; for(int j=0; j<a[i].length; j++) { System.arraycopy(A[i], 0, B[i], 0, A[i].length); System.out.println( "B = " + Arrays.deepToString( B ) ); clone() clone 2.87 ArrayCloneExample.java ( ) package section0218; import java.util.arrays; public class ArrayCloneExample { // int[] x = { 1, 3, 0, -2, 4 ; int[] y = x.clone(); x[0] = 0; // Deep copy // y System.out.println( "y = " + Arrays.toString( y ) ); // int[][] A = { {1, 3, 0, {-2, 4 ; int[][] B = new int[a.length][];

116 102 2 Java I for(int i=0; i<a.length; i++) { B[i] = A[i].clone(); A[0][0] = 0; // Deep copy // B System.out.println( Arrays.deepToString( B )); clone arraycopy arraycopy clone Java 'A' "A" 1 ( String S) (^^;) String String char String ( ) " " ( ) String String hello; ; 1 String hello = " "; char String char Unicode ( ) String "" String char '' 'a' "a" char String 2.88 package section0219; public class StringvsChar { char a = 'a'; a = 'b'; System.out.println( a ); String s = "a"; s = "b"; StringvsChar.java ( )

117 System.out.println( s ); ( ) ( 'a' ) ( 'b' 'a' ) a a s b a b 2.27 ( "a" s ) (C ) ( "b" ) ( s ) ( "a" ) ( ) char String String 2.89 StringMethods.java ( ) package section0219; public class StringMethods { String name = " "; int length = name.length(); // System.out.println( "\"" + name + "\" " + length + " " ); int sep = name.indexof( " " ); // String familyname = name.substring(0, sep); // String firstname = name.substring(sep+1); System.out.println( " :" + familyname ); System.out.println( " :" + firstname ); String name length indexof substring String

118 104 2 Java I length length() 4 indexof 0 1 sep = 2 substring 2 "abcdefg".substring( 3 ) "defg" ( 0 ) "abcdefg".substring( 2, 5 ) "cde" String StringMethods \" 2 2 (""") 1 2 \" ( ) Java ( ) \b \n \r ( ) \t \u Unicode ( \u3042) \\ \' 1 \" Windows UNIX (MacOS ) MacOS UNIX (Linux ) MacOS UNIX 2 Windows \r\n UNIX \n OS Java Unicode Eclipse Eclipse UTF-8 UNICODE Unix UNIX

119 2.20 ( ) 105 Eclipse UNIX Windows (^^;) 2.20 ( ) (sorting) Java API ( ) (sorting method) 2.90 MyTools.java ( ) package section0220; import java.util.arrays; public class MyTools { /** * n min max */ public static int[] makerandomintarray( int n, int min, int max ) { int[] array = new int[n]; for(int i=0; i<n; i++) { array[i] = (int)( Math.random() * ( max - min + 1 ) ) + min; return array; /** * name array n : n 2n */ public static void printintarray( String name, int[] array, int n ) { System.out.print( name + ": " ); if( n*2 >= array.length ) { // System.out.println( Arrays.toString( array ) ); else { // n System.out.print( "[" ); for(int i=0; i<n; i++) { System.out.print( array[i] + ", " ); System.out.print( "..." ); for(int i=array.length-n; i<array.length; i++) { System.out.print( ", " + array[i] ); System.out.println( "]" );

120 106 2 Java I /** * array i j */ public static void swap( int[] array, int i, int j ) { int dummy = array[i]; array[i] = array[j]; array[j] = dummy; printintarray Arrays tostring() (Selection sort) 最小値 1を見つけ 先頭 5と交換する 次に小さな値 2を見つけ 3と交換する SortingExample.java ( ) package section0220; public class SortingExample { // [1,1000] 1000 int[] data = MyTools.makeRandomIntArray( 1000, 1, 1000 ); MyTools.printIntArray( " ", data, 5 ); /* * * * * */ int[] array = new int[data.length];

121 2.20 ( ) 107 System.arraycopy( data, 0, array, 0, data.length ); // long starttime = System.nanoTime(); ArraySorting.selectionSort( array ); long endtime = System.nanoTime(); MyTools.printIntArray( " ", array, 5 ); printtime( endtime - starttime ); // private static void printtime( long time ) { System.out.printf( " : %10d nsec (10^-9 sec)%n", time ); 2.92 ArraySorting.java#selectionSort ( ) package section0220; public class ArraySorting { /** * (Selection method) array */ public static void selectionsort( int[] array ) { for(int i=0; i<array.length - 1; i++) { int min = i; for(int j=i+1; j<array.length; j++) { if( array[j] < array[min] ) min = j; MyTools.swap( array, i, min ); System.nanoTime() min,i,j Java ( ) (Insertion sort)

122 108 2 Java I 既に整列の済んでいる部分に新たに4を挿入する 4を挿入するには 7と5を移動させて空きを作ってから次は2を挿入するので 4つの値を移動させる SortingExample.java#main ( ) // main System.arraycopy( data, 0, array, 0, data.length ); // starttime = System.nanoTime(); ArraySorting.insertionSort( array ); endtime = System.nanoTime(); MyTools.printIntArray( " ", array, 5 ); printtime( endtime - starttime ); 2.94 ArraySorting.java#selectionSort ( ) // (selectionsort ) /** * (Insertion method) array */ public static void insertionsort( int[] array ) { for(int i=1; i<array.length; i++) { int val = array[i]; int j = i; while( j > 0 ) { if( array[j-1] <= val ) break; array[j] = array[j-1]; j--; array[j] = val; (Bubble sort) ( )

123 2.20 ( ) 109 ( ) 隣り合う 2 つを比較 順序が逆のとき交換する 順に比較していくと 途中から最大値が 右に移動を始める 回目の走査で 最大値が最後尾に 次は 残りの要素で再度走査を行う SortingExample.java#main ( ) // main System.arraycopy( data, 0, array, 0, data.length ); // starttime = System.nanoTime(); ArraySorting.bubbleSort( array ); endtime = System.nanoTime(); MyTools.printIntArray( " ", array, 5 ); printtime( endtime - starttime ); 2.96 ArraySorting.java#bubbleSort ( ) // (insertionsort ) /** * (Bubble sorting method) array */ public static void bubblesort( int[] array ) { for(int i=array.length - 1; i>=1; i--) { for(int j=0; j<i; j++) { if( array[j] > array[j+1] ) MyTools.swap( array, j, j+1 );

124 110 2 Java I (Quicksort) (Divide and Conquer method) 1960 ( ) ( ) center left right i j 左より center より大きな値 右より center より小さな値を見つけては交換する操作をすれ違うまで行う i j 分割した列ごとに 再帰的に クィックソートを施していく 2.31 ( ) 2.97 SortingExample.java#main ( ) // main System.arraycopy( data, 0, array, 0, data.length ); // starttime = System.nanoTime(); ArraySorting.quickSort( array ); endtime = System.nanoTime(); MyTools.printIntArray( "quick ", array, 5 ); printtime( endtime - starttime );

125 2.20 ( ) ArraySorting.java#quickSort ( ) // (bubblesort ) /** * (Quick sorting method) array */ public static void quicksort( int[] array ) { quicksort( array, 0, array.length - 1 ); private static void quicksort( int[] array, int left, int right ) { if( left >= right ) return; int center = (array[left] + array[(left + right)/2] + array[right])/3; int i = left; int j = right; while( i<= j ) { while( array[i] < center ) i++; while( array[j] > center ) j--; if( i <= j ) { MyTools.swap( array, i, j ); i++; j--; quicksort( array, left, j ); quicksort( array, i, right ); (Heap sort) (Heap tree) [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] [0] 5 [1] [2] 6 3 [3] [4] [5] [6] [7] [8] [9] ( ) (tree structure) 2.32 (root)

126 112 2 Java I ( ) (leaces) (inner node) ( ) (binary tree) ( 2.32 ) = = n n/2 ( ) ( ) ( ) ( ) ( ) a b c [n/2] [0] ( 2.32 [4] [0] )

127 2.20 ( ) SortingExample.java#main ( ) // main System.arraycopy( data, 0, array, 0, data.length ); // starttime = System.nanoTime(); ArraySorting.heapSort( array ); endtime = System.nanoTime(); MyTools.printIntArray( "heap ", array, 5 ); printtime( endtime - starttime ); ArraySorting.java#heapSort ( ) // (quicksort ) /** * (Heap sorting method) array */ public static void heapsort( int[] array ) { buildheap( array ); for(int i=array.length-1; i>0; i--) { MyTools.swap( array, 0, i ); heapupdate( array, 0, i ); private static void buildheap( int[] array ) { for(int i=array.length/2-1; i>=0; i--) { heapupdate( array, i, array.length ); private static void heapupdate( int[] array, int parent, int last ) { int left_child = 2 * parent + 1; int right_child = left_child + 1; int largest = parent; if( left_child < last && array[left_child] > array[largest] ) largest = left_child; if( right_child < last && array[right_child] > array[largest] ) largest = right_child; if( largest!= parent ) { MyTools.swap( array, parent, largest ); heapupdate( array, largest, last ); n O(n log n) O(n log n) ( ) (Merge sort)

128 114 2 Java I k 2k k 2k ( ) array array array array array SortingExample.java#main ( ) // main System.arraycopy( data, 0, array, 0, data.length ); // starttime = System.nanoTime(); ArraySorting.mergeSort( array ); endtime = System.nanoTime(); MyTools.printIntArray( "merge ", array, 5 ); printtime( endtime - starttime ); ArraySorting.java#mergeSort ( ) // (heapsort ) /** * (Merge sorting method) array */ public static void mergesort( int[] array ) { int[] array2 = new int[array.length]; int size = 1; while( size < array.length ) {

129 2.20 ( ) 115 merge( array, array2, size ); merge( array2, array, 2 * size ); size *= 4; private static void merge( int[] from, int[] to, int size ) { int start = 0; while( start < from.length ) { int k = start; int i = start; int j = start + size; int iend = Math.min( start + size, from.length ); int jend = Math.min( start + 2 * size, from.length ); while( i < iend && j < jend ) { if( from[i] < from[j] ) to[k++] = from[i++]; else to[k++] = from[j++]; while( i < iend ) to[k++] = from[i++]; while( j < jend ) to[k++] = from[j++]; start += 2 * size; (Shell s sort) D.L.Shell 1959 h n {h i : h i+1 = 3h i +1, h 1 = 1, h i < n O(n 1.25 ) Knuth ({h i = {1, 4, 13, 40, 121, 364,... ) h = 4 離れた ( 同じ色 ) 同士で挿入法ソートを実行 h = 1 : デフォルトの挿入法を実行 SortingExample.java#main ( ) // main System.arraycopy( data, 0, array, 0, data.length ); //

130 116 2 Java I starttime = System.nanoTime(); ArraySorting.shellSort( array ); endtime = System.nanoTime(); MyTools.printIntArray( "Shell ", array, 5 ); printtime( endtime - starttime ); ArraySorting.java#shellSort ( ) // (mergesort ) /** * (Shell's sorting method) array */ public static void shellsort( int[] array ) { int h = 1; while( h < array.length / 3 ) { h = 3 * h + 1; while( h > 0 ) { for(int i=h; i<array.length; i++) { int dummy = array[i]; // int j = i; while( j > h-1 && array[j-h] >= dummy ) { array[j] = array[j-h]; j -= h; array[j] = dummy; // h = (h - 1)/3; Java Java System.currentTimeMillis() (1 msec = 10 3 sec) System.nanoTime() (1 nsec = 10 9 sec) currenttimemillis() nanotime() API TimePrecisionExample.java ( )

131 2.20 ( ) 117 package section0220; public class TimePrecisionExample { final int N = ; int count = 50; int x = 0; for(int k=0; k<count; k++) { long starttime = System.nanoTime(); for(int i=0; i<n; i++) { x++; long endtime = System.nanoTime(); System.out.printf( "%d nsec%n", (endtime - starttime) ); System.out.println( "x = " + x ); Windows 10 Pro / Intel Core i5-3337u 1.80GHz MacOS X / Intel Core i7 2.20GHzz ( x 1 N ) Java Java class JVM ( ) (Windows 0 Mac 38) 0 nsec Windows MacOS Windows nsec (?) 570 nsec (?) MacOS k Windows MacOS X k Windows MacOS X Java N N 0

132 118 2 Java I Java Java Java ( n n (Windows)

133 int a = 123 / 4 % 8; 2. double x = (double) 123 / 4; 3. int a = 1; int b = 2; String s = " " + a + b; 4. int a = 10; int b = a++; 5. int a = 12; a /= 5; ( ) WrongAverage.java ( ) pakage section0220; pablic class WrongAverage { pablic void mein(string[] args) { int a = { 1, 3, -2, 5, 2, 0, 9 ; int i; for(i=1; i<=7; i++) { int sum += a[i]; ; double average = sum / a.length; system.out.println( " ", average, " " ); SwapRowOfMatrix.java ( ) package section0221; public class SwapRowOfMatrix { int[][] A = {{1, 2, 3, 4, {5, 6, 7, 8, {9, 10, 11, 12; int i = 0; int j = 2; // A i j // printf

134 120 2 Java I for(int i=0; i<a.length; i++) { for(int j=0; j<a[i].length; j++) { System.out.printf( "%3d", A[i][j]); System.out.println(); ( ) 1. \ =, = Java a for ( for( 1; 2; 3) ) 1. i i = 0, 2, 4,, i i = 5, 10, 15, 20,, i i = 1, 5, 25, 125, 625, x x = 0.0, 0.01, 0.02,, 1.0 x 1.0

135 n 1. n 2. Math.random() n [0, 1) x = (x 1, x 2,, x n ) Ã n 3. x x = 4. x 1 y y = x x 5. y i=1 x 2 i VectorNormalize.java ( ) package section0221; import java.util.scanner; public class VectorNormalize { // (1) Scanner scan = new Scanner(System.in); System.out.println(" "); int n = scan.nextint(); // (2)(3)(4) // (5) System.out.println( " "); for(int i=0; i<n; i++) { System.out.println( "y[" + i + "]=" + y[i] ); n C m n m n n C 0, nc 1, nc 2,..., nc n 1, nc n Combination.java (n, m) n C m long n package section0221; import java.util.scanner; public class Combination { Combination.java ( )

136 122 2 Java I Scanner scan = new Scanner(System.in); System.out.println("n "); int n = scan.nextint(); for(int m=0; m<=n; m++) { // ncm comb long comb = // comb System.out.println( "(" + n + "," + m +")=" + comb ); e x e = e 1 e x = n=0 x n n! n = 0 n 1 0! + 1 1! + 1 2! n! for e = package section0221; public class Maclaurin { double x = 1.0; Maclaurin.java ( e ) // // // x [1, 3] (^^;) f(x) = sin ( e cos x x log x) 3 1 f(x) dx

137 double dx = ; sum = 0; for(double x = 1; x<=3-dx; x+=dx) sum += f(x)*dx sum Math 1. sin(x) Math.sin( x ); 2. cos(x) Math.cos( x ); 3. log(x) Math.log( x ); 4. e x Math.exp( x ); Mathematica dx = dx = 0.1 dx R T T R p R T p (0, 0), (1, 0), (1, 1), (0, 1) 4 T T 1 ( ) R T (x, y) 100, 000 R 1 100, 000 p T 1 R p π R π/4... Math.random() [0, 1) double double x = Math.random(); double y = Math.random(); (x, y)

138 124 2 Java I MonteCarlo.java ( ) package section0221; public class MonteCarlo { int count = ; // // count // 1 // p ( ) a b c a b 1 MargeArrays.java 2 a b MargeArrays.java ( ) package section0221; import java.util.arrays; public class MargeArrays { int[] a = { 2, 5, 7, 8, 12, 15, 21, 24, 25; int[] b = { 1, 4, 5, 9, 11, 23, 26, 30; int[] c = new int[a.length+b.length]; // // System.out.println( "c = " + Array.toString( c ) );

139 m 1 a m 2 b ArrayTransform.java ArrayTransform.java ( ) package section0221; import java.util.scanner; public class ArrayTransform { int[] a = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15; // Scanner m // a m // n // b int[][] b = new int[n][m]; // a b // 0 // b for(int i = 0; i < b.length; i++) { for(int j = 0; j < b[i].length; j++) { System.out.printf( b[i][j] + "\t" ); // "\t" System.out.println(); b Math.random() double [0, 1) ( ) 1. (0, 1] double rand int rand

140 126 2 Java I 3. true false boolean rand n n 1. n n p[][] p[i][j] = ß 1 (i = 0 j = 0) p[i 1][j] + p[i][j 1] (i 0 & j = 0) 2. n p[] n p[j] = ß 1 (j = 0) p[j 1] + p[j] (j = 1, 2,..., n 1) 3. p[i][j] = i+j C j (i, j = 0,..., n 1) 4. 1 (i = 0 j = 0) p[i][j] = i + j p[i][j 1] j (i 0 & j = 1, 2,..., n 1) InverseMatrix.java 1. n n A = (a ij ) n 2n B = (b ij ) A 2. i = 1, 2,..., n B i b ii (b ii = 1 ) k = 1, 2,..., n (k i) k i b ki 3. A 1 b ii 0

141 InverseMatrix.java ( ) package section0221; public class InverseMatrix { double[][] A = { {2, 6, 9, {1, 4, 6, {0, 1, 2 ; double[][] B = new double[a.length][a[0].length*2]; // B printmatrix( "%5.1f", "B", B ); // B printmatrix( "%5.1f", "B", B ); // A static void printmatrix( String format, String name, double[][] A ) { System.out.println( name + " = "); for(int i=0; i<a.length; i++) { for(int j=0; j<a[0].length; j++) { System.out.printf( format, A[i][j] ); System.out.println(); System.out.println(); // B B = // B =

142 II Java 2

143 129 3 Java II 3.1 (Object oriented) ( ) (Programming paradigm) ( ) COBOL (1959) BCPL (1966) Perl (1987) PHP (1995) Ruby (1993) FORTRAN (1954) Algol (1958) Lisp (1958) PL/I (1964) BASIC (1963) Simlula (1964) C (1971) PASCAL (1969) Smalltalk (1969) Scheme (1975) ML (1973) Ada (1979) C++ (1983) Common Lisp (1984) Tcl/Tk (1988) Python (1991) Java (1991) Haskell (1990) Delphi (1995) JavaScript (1995) OCaml (1996) C# (2001) Swift (2010) Computer Languages Timeline ( などより抜粋 3.1 ( ) FORTRAN ( ) (Procedural) 2 Java C (

144 130 3 Java II ) ( object) ( (^^;)) Java Java (Functional programming) Java (Aspect oriented) Java AspectJ Java ( Wikipedia: ) 3 (encapsulation) (inheritance) (polymorphism) (dynamic binding) ( ) (property) (method) GPA (^^;) (object) (instance)

145 (Database : ) 2000 Java (^_^;) Java main 3.1 Student.java ( ) package section0302; // public class Student { // private int idno; // private String name; // private int countcourses; // private Course[] course; // private static final int MAXCOUNT_COURSES = 100; // // public Student( int idno, String name ) { this.idno = idno; this.name = name; this.countcourses = 0; this.course = new Course[MAXCOUNT_COURSES]; // // public void addrecord( Course course ) { this.course[countcourses++] = course; // public void printrecords() { System.out.println( idno + ":" + name + " " ); if( countcourses == 0 ) { System.out.println( " " ); return; for(int i=0; i<countcourses; i++) { System.out.printf( " %s %d %n", course[i].gettitle(), course[i].getdegree() ); this.printaverage(); //

146 132 3 Java II private void printaverage() { int sum = 0; for(int i=0; i<countcourses; i++) { sum += course[i].getdegree(); System.out.printf( " %f %n", (double) sum / countcourses ); main Java main main ( ) Java Applet Java main ( Java Applet Java 9 HTML5 JavaScript JavaScript Java ) (Pascal-case) ( ) 3 ( ) (field) (constructor) (method) 3 ( ) main ( HelloJava HelloJava main ) Course StudentExample section StudentExample.java ( ) package section0302; // public class StudentExample { // Student noda = new Student( , " "); // noda.addrecord( new Course(" ", 85) ); noda.addrecord( new Course(" ", 77) ); noda.addrecord( new Course(" ", 96) ); // noda.printrecords();

147 package section0302; // public class Course { // // private String title; // private int degree; // public Course( String title, int degree ) { this.title = title; this.degree = degree; // // public String gettitle() { return title; // public int getdegree() { return degree; Course.java ( ) main ( ) Java main public public ( )

148 134 3 Java II ( ) ( ) ( ) Java Student StudentExample.java main ( 3.2 ) ( ) section0302 Student.java Student Student noda = new Student( , " "); Student noda ( ) noda ( 3.2 ) noda Student Student ( Student noda ) 2 8 String int[] String name = " "; int[] a = {1, 2, 3; name a noda new Student( , " "); noda Student new Student( , " ") Student 1 int 2 Student ( )

149 noda Student 型インスタンス 参照 private idno private name 野田愛 private countcourses 0 Course[ ] course public void addrecord( Record ) public void printrecords() private void printaverage() 3.2 ( void ) ( 3.2 ) static ( ) ( ) this.idno = idno; this.name = name; Eclipse 3.4 Eclipse // private int idno; // private String name; // private int countcourses; // private Course[] cours; // private static final int MAXCOUNT COURSES = 100; // // Student( int idno, String name ) { this.idno = idno; this.name = name; this.countcourses = 0; this.cours = new Course[MAXCOUNT COURSES]; this.idno = idno; idno 2 idno 1 private int idno; idno idno idno 2 this.

150 136 3 Java II this. this.idno ( idno) this. 2 Student( int idnum, String sname ) this. idno = idnum; this. idno idno ( ) 3.5 this. private int idno; // private String name; // private int countcourses; // private Course[] cours; // private static final int MAXCOUNT COURSES = 100; // // Student( int idnum, String sname ) { idno = idnum; name = sname; countcourses = 0; cours = new Course[MAXCOUNT COURSES]; this. ( ) this. this.countcourses = 0; this.course = new Course[MAXCOUNT_COURSES]; this. this. 1 ( ) 3.6 ( ) StudentExample.java ( ) package section0302; // public class StudentExample { // Student noda = new Student( , " "); // noda.addrecord( new Course(" ", 85) ); noda.addrecord( new Course(" ", 77) ); noda.addrecord( new Course(" ", 96) ); Student kagura = new Student( , " ", 19 ); // // noda.printrecords(); kagura.printrecords();

151 (String, double ) (String, double ) ( ) (String, double ) (String, int ) Student kagura = new Student(" ", 80); 80 Weight Height Age Student(String, Age ) Student(String, Weight ) Age Weight Student kagura = new Student( , " ", 80); Student kagura = new Student( , " ", new Weight(80)); 80 ( ) (overload) Student 3.7 ( ) Student.java ( ) package section0302; // public class Student { // private int idno; // private String name; // private int age; // private int countcourses; // private Course[] course; // private static final int MAXCOUNT_COURSES = 100; // private static final int UNDEFINED_IDNO = 0; // private static final String UNDEFINED_NAME = ""; // private static final int UNDEFINED_AGE = -1; // // public Student() { this.idno = UNDEFINED_IDNO; this.name = UNDEFINED_NAME;

152 138 3 Java II this.age = UNDEFINED_AGE; this.countcourses = 0; this.course = new Course[MAXCOUNT_COURSES]; // public Student( int idno, String name ) { this(); this.idno = idno; this.name = name; // public Student( int idno, String name, int age ) { this( idno, name ); this.age = age; // printrecords() // public void printrecords() { String strage = (age == UNDEFINED_AGE)? "": String.valueOf(age); System.out.println( idno + ":" + name + " (" + strage + ") " ); if( countcourses == 0 ) { System.out.println( " " ); return; for(int i=0; i<countcourses; i++) { System.out.printf( " %s %d %n", course[i].gettitle(), course[i].getdegree() ); this.printaverage(); (default constructor) UNDEFINED_ private static final final ( ) this.idno = 0; 0 this.idno = 0; this.idno = UNDEFINED_IDNO; this() this( idno, name ) this(...)

153 this();,, ) // public Student() { this.idno = UNDEFINED_IDNO; this.name = UNDEFINED_NAME; this.age = UNDEFINED_AGE; this.countcourses = 0; this.course = new Course[MAXCOUNT_COURSES]; // public Student( int idno, String name ) { this.idno = idno; this.name = name; this.age = UNDEFINED_AGE; this.countcourses = 0; this.course = new Course[MAXCOUNT_COURSES]; // public Student( int idno, String name, int age ) { this.idno = idno; this.name = name; this.age = age; this.countcourses = 0; this.course = new Course[MAXCOUNT_COURSES]; UNDEFINED_AGE Eclipse countcourses numcourses

154 140 3 Java II this(...) ( ) Student sex Student( int idno, String name, String sex ) ( ) Student katushika = new Student( , " ", " "); katushika.printrecords(); Point PointExample main Point p = new Point(); Point 3.8 Point.java ( ) package section0302; // public class Point { private double x; private double y; // public void setx( double x ) { this.x = x; public void sety( double y ) { this.y = y; // public double getx() { return this.x; public double gety() { return this.y; // public void print() { System.out.printf( "(%f,%f)%n", this.x, this.y ); 3.9 package section0302; public class PointExample { PointExample.java ( )

155 Point p = new Point(); // p p.setx( 1.5 ); // p x 1.5 p.sety( -0.3 ); // p y -0.3 p.print(); // p (setter) set ( x void setx( double ) ) (getter) return p x double px = p.getx(); px 1.5 get ( ) Point( double x, double y ) ( ) ( ) Point 2 PointExample main p ( ) ( ) (instance field) ( ) idno idno (class field) ( )

156 142 3 Java II static Student MAXCOUNT_COURSES static 3.10 ( ) Student.java ( ) package section0302; public class Student { private int idno; // private String name; // private int age; // private String sex; // private int countcourses; // private Course[] course; // private static final int MAXCOUNT_COURSES = 100; // private static final int UNDEFINED_IDNO = 0; // private static final String UNDEFINED_NAME = ""; // private static final int UNDEFINED_AGE = -1; // private static final String UNDEFINED_SEX = ""; // public static final String UNIV_NAME = " "; // // ( ) final final (^^;) private int idno = UNDEFINED_IDNO; // Student final 3.11 package section0302; public class MembershipExample { MembershipExample.java ( )

157 int n = 100; // Entry entry = new Entry( n ); // entry.add(" ", 19 ); entry.add(" ", 20 ); entry.add(" ", 18 ); entry.print(); 3.12 Entry.java ( ) package section0302; public class Entry { private int membercount; private Member[] member; private static int memberno = 1000; // final public Entry( int n ) { member = new Member[ n ]; membercount = 0; public void add(string name, int age) { memberno++; // member[membercount++] = new Member( memberno, name, age ); public void print() { System.out.println( " " + membercount ); for(int i=0; i<membercount; i++) { member[i].printrecords(); 3.13 Member.java ( ) package section0302; public class Member { private int idno; private String name; private int age; Member( int idno, String name, int age ) { this.idno = idno; this.name = name; this.age = age; void printrecords() { System.out.printf( "%03d %s (%2d)%n", idno, name, age );

158 144 3 Java II ( -1 ) 2. noda.idno katushika.name ( ) int idno = noda.idno idno. Student.UNIV_NAME noda.univname (Eclipse ) Student.idNo ( ) Point getx() gety() getidno() Point package section0302; // public class Point { private double x; private double y; : 3.14 Point // public double getx() { return this.x; public double gety() { return this.y; x y private Point Point p = new Point(); Point p.x = 1.5; p.y = -0.3; ( )

159 (access modifier) ( ) int mymoney 0 private ( ) ( ) ( ) private ( ) private public ( ) Student.java 1. idno 2. idno 3. printrecords() i 4. printaverage() sum ( ) (i sum) (local variable) (instance method) (class method) main printcirclearea( r ); ( static ) 3.15 package section0218; public class CircleArea2 { CircleArea2.java ( )

160 146 3 Java II for(int r=1; r<=10; r++) { printcirclearea( r ); // radius area static void printcirclearea( int r ) { double area = r * r * Math.PI; System.out.printf( " =%2d %8.4f %n", r, area );.printcirclearea( r ) CircleArea2.printCircleArea( r ); CircleArea2 ( ) Math.cos(double) Math Math. import (import ) Student printrecords() (static ) noda.printrecords(); kagura.printrecords(); ( ) Human String name " " Human taro taro hello TaroExample.java (?) ( ) 3.16 TaroExample.java ( ) package section0302; public class TaroExample { String name = " "; hello( name, "10:00" ); static void hello( String name, String time ) { System.out.print( name + " " + time + " " ); if( time.compareto("12:00") <= 0 ) { // "12:00" System.out.println( " " ); else { System.out.println( " " );

161 main 3.8 Point public double length() double Math.sqrt(double) 3.17 ( ) PointExample.java package section0302; public class PointExample { Point p = new Point(); // p Point q = new Point( 1.5, -0.3 ); p.print(); // p q.print(); // System.out.println( " p " + p.length() ); Point public static double distance( Point, Point ) public double distance( Point ) (0,0) private static final Point ORIGIN length() ORIGIN 3.18 PointExample2.java package section0302; public class PointExample2 { Point p = new Point( 1.0, 2.0 ); Point q = new Point( 2.0, -1.0 ); // double dist1 = Point.distance( p, q ); System.out.println( "p q ( ) " + dist1 ); // double dist2 = p.distance( q ); System.out.println( "p q ( ) " + dist2 );

162 148 3 Java II ComplexNumber 3.19 ComplexNumberExample.java ( ) package section0302; public class ComplexNumberExample { ComplexNumber c1 = new ComplexNumber( 1, 2 ); // c1 = 1 + 2i ComplexNumber c2 = new ComplexNumber( 2,-3 ); // c2 = 2-3i System.out.println("c1 = " + c1.tostring() ); System.out.println("c2 = " + c2.tostring() ); // System.out.println("c1 + c2 = " + c1.add( c2 ).tostring() ); System.out.println("c2 + c1 = " + c2.add( c1 ).tostring() ); System.out.println("c1 + c2 = " + ComplexNumber.add( c1, c2 ).tostring() ); System.out.println("c1 * c2 = " + c1.multiply( c2 ).tostring() ); 3.20 ComplexNumber.java ( ) package section0302; public class ComplexNumber { private double real; // private double imag; // public ComplexNumber( double r, double i ) { this.real = r; this.imag = i; // "( real, imag public String tostring() { // // c public ComplexNumber add( ComplexNumber c ) { // // public static ComplexNumber add( ComplexNumber c1, ComplexNumber c2 ) { // // c public ComplexNumber multiply( ComplexNumber c ) { //

163 ComplexNumber (Annotation ) ( Java public void setreal(double) public ComplexNumber conjugate() public ComplexNumber divide(double) public ComplexNumber divide(complexnumber) public double abs() ( ) public double angle() x + iy θ θ = ( y arctan (x > 0) x) ( y arctan + π (x < 0, y 0) x) ( y arctan π (x < 0, y < 0) x) π/2 (x = 0, y > 0) π/2 (x = 0, y < 0) = 2 arctan Å x2 +y 2 x Math.atan2(y,x) y ã (y 0), 0 (x > 0, y = 0), π (x < 0, y = 0) Point section0302 Line ax + by + c = 0 Line 3 a, b, c 4 3 a, b, c Line( double a, double b, double c ) ( ) y ( ) Line( double m, double d ) 2 (Point ) Line( Point p, Point q ) (Point ) ( ) Line( Point p, double m ) true boolean online( Point p )

164 150 3 Java II double distance( Point p ) true boolean iscross( Line other ) Point Point crosspoint( Line other ) 2 NULL true static boolean online( Line, Point ) static double distance( Line, Point ) true static boolean iscross( Line, Line ) static Point crosspoint( Line, Line ) public Circle private Point center ( ) double r ( ) public Circle( Point, double ) public double area() public String tostring() :(1.0, 2.0) :3.0 public double distance( Point ) 2 ( ) true public boolean includes( Point ) ( ) true public boolean iscross( Circle ) MyMath plus() 3.21 package section0302; public class MyMathExample { MyMathExample.java ( Math )

165 System.out.println( MyMath.plus( 10, 20 ) ); System.out.println( MyMath.plus( 10, 20, 30 ) ); System.out.println( MyMath.plus( 10.0, 20.0 ) ); System.out.println( MyMath.plus( new int[]{ 1, 2, 3, 4, 5 ) ); package section0302; public class Problem0302 { int a; a = 123; package section0302; public class Problem0302 { int a; this.a = 123; main a 123 main a = 123; (?) ( int[]) int[] x = new int[10]; x ( ) (String[]) 2 (int[][]) (Point ) Point Point centroid( Point[] ) Point 3.22 package section0302; public class CentroidExample { Point[] points = { new Point( 0.5, 1.8 ), CentroidExample.java ( Point[])

166 152 3 Java II new Point( 1.2, 0.9 ), new Point( 1.5, 3.2 ), new Point( 1.7, 2.2 ), new Point( 3.0, 0.7 ), new Point( 3.3, 3.1 ), ; Point.centroid( points ).print(); package section0302; // public class Point { private double x; private double y; 3.23 Point.java ( centroid ) // public static Point centroid( Point[] points ) { double xsum = 0.; double ysum = 0.; for( Point p : points ) { xsum += p.x; ysum += p.y; return new Point( xsum/points.length, ysum/points.length ); main 12 Point.centroid( points ).print(); OK Point.centroid( points ) Point centroid() points ( ) Point.print() print() ( ) Point centroid print() // Point.centroid( points ).print(); Point centroid = Point.centroid( points ); centroid.print(); CentroidExample.java main ( ) points new Point( 3.3, 3.1 ) ( ) C (C ++ OK) ( Java )

167 int[] a = { 1, 2, 3, ; (Overload) Math.abs() int Math.abs(int) long Math.abs(long) float Math.abs(float) double Math.abs(double) Java ( ) ( ) public private (access modifier) Java ( ) (package-private ) private (package-private) protected public ( )

168 154 3 Java II private protected (inner class) private int x = 123; public static double[] x = new double[100]; private private 3.24 PrivateFieldExample.java (private field ) package section0303; public class PrivateFieldExample { Circle circle = new Circle( 10.0 ); double radius = circle.radius; double area = circle.getarea(); System.out.printf(" %f %f%n", radius, area ); class Circle { // private double radius; // Circle( double radius ) { // this.radius = radius; double getarea() { // return radius * radius * Math.PI; Cirlce radius private main double radius = circle.radius; radius Circle PrivateFieldExample. getarea() private double area = circle.getarea(); radius private ( package-private ) radius circle.radius private private main circle.radius = ; (^^;) ( ) private

169 ( )PrivateFieldExample.java (private field ) package section0303; public class PrivateFieldExample { Circle circle = new Circle( 10.0 ); double radius = circle.getradius(); double area = circle.getarea(); System.out.printf(" %f %f%n", radius, area ); class Circle { // private double radius; // Circle( double radius ) { // this.radius = radius; double getradius() { // return this.radius; double getarea() { // return radius * radius * Math.PI; Circle double hankei; PrivateFieldExample circle.radius; circle.hankei; radius circle.getradius() getradius() return hankei; Circle section0303 Circle.java (package-private ) private private private cos() Math Math Math Math private

170 156 3 Java II Math private ( ) private package-private ( ) (package-private) package-private public public package-private public package-private protected protected 2 (package-private ) ( ) protected package-private protected ( ) public public 4 package-private A public a() A public a() package section0303; public class Problem0332 {

171 3.4 ( ) 157 A a1 = new A(); a1.setvalue( 10 ); System.out.println( a1.value ); A a2 = new A( 10 ); System.out.println( a2.getvalue() ); class A { private int value; A( int value ) { this.value = value; void setvalue( int value ) { this.value = value; int getvalue() { return this.value; A section0303a (Eclipse import ) public public public ( ) 3.4 ( ) Java ( inheritance)

172 158 3 Java II 1 (super class) (sub class) ( subset ) Java ( ) 3.26 InheritanceExample.java ( ) package section0304; public class InheritanceExample { Student noda = new Student( , " " ); Professor hasiguchi = new Professor( " ", " ", " " ); Lecture linearalgebra1 = new Lecture( "A001", " " ); noda.take( linearalgebra1 ); hasiguchi.lectured( linearalgebra1 ); 3.27 Human.java ( ) package section0304; // public class Human { private String name; // private int age; // private String sex; // public static final String NAME_UNKNOWN = null; // public static final int AGE_UNKNOWN = -1; // public static final String SEX_UNKNOWN = null; // // public Human( String name, int age, String sex ) { this.name = name; this.age = age; this.sex = sex; // public String getname() { return this.name; public int getage() { return this.age;

173 3.4 ( ) 159 public String getsex() { return this.sex; 3.28 Professor.java ( ) package section0304; // public class Professor extends Human { private String licence; // // public Professor( String licence, String name, String sex ) { super( name, AGE_UNKNOWN, sex ); this.licence = licence; // public void lectured( Lecture lecture ) { System.out.printf( "(%s) %s %s %n", this.licence, this.getname(), lecture.getname() ); 3.29 package section0304; // public class Lecture { private String lecno; // private String lecname; // // public Lecture( String lno, String lname ) { this.lecno = lno; this.lecname = lname; // public String getlecno() { return lecno; public String getname() { return lecname; Lecture.java ( ) 3.30 package section0304; public class Student extends Human { private int idno; // // public Student( int idno, String name ) { Student.java ( )

174 160 3 Java II super( name, AGE_UNKNOWN, SEX_UNKNOWN ); this.idno = idno; // public void take( Lecture lecture ) { System.out.printf( "%s(%d) %s %n", this.getname(), this.idno, lecture.getname() ); class extends extends 3.4 UML (Unified Modeling Language) (class diagram) UML UML UML Java ( ) Human Student ( ) Java Student Human Human - name : String - age : int - sex : String + NAME_UNKNOWN : String = null + AGE_UNKNOWN : int = -1 + SEX_UNKNOWN : String = null + getname() : String + getage() : int + getsex() : String <<constructor>> + Human(name : String, age : int, sex : String ) - lecno : String - lecname : String Lecture + getlecno() : String + getname() : String <<constructor>> + Lecture( lno : String, lname : String ) + public # protected ~ package private - private 可視性 - idno : int Student - licence : String Professor + take( lecture : Lecture ) : void <<constructor>> + Student( idno : int, name : String ) + lectured( lecture : Lecture ) <<constructor>> + Professor( licence : String, name : String, sex : String ) 3.4 UML Point WeightedPoint WeightedPoint 2 WeightedPoint centroid( WeightedPoint )

175 3.4 ( ) PointExample3.java ( ) package section0304; public class PointExample3 { // double[][] data = { {0.5, 1.8, 2, {1.2, 0.9, 1, {1.5, 3.2, 3, {1.7, 2.4, 2, {2.5, 3.9, 4, {1.9, 2.2, 1, {3.0, 0.7, 3, {3.5, 3.1, 2, {4.2, 1.9, 2, {4.0, 3.7, 1 ; // points[] WeightedPoint[] points = new WeightedPoint[data.length]; for(int i=0; i<points.length; i++) { points[i] = new WeightedPoint( data[i][0], data[i][1], data[i][2] ); // ( ) WeightedPoint center = new WeightedPoint( points[0] ); // center points[i] center for(int i=1; i<points.length; i++) { center = center.centroid( points[i] ); // ( ) System.out.print( " " ); center.print(); 3.32 package section0304; import section0302.point; public class WeightedPoint extends Point { private double weight; // WeightedPoint.java ( ) // centroid 3.22 n A B B C ( 3.5 ) A A a ( ) B b C

176 162 3 Java II c A insta insta A a B b c C + c : int insta B + b : int A + a : int クラスAのインスタンス型 int a int b int c クラスBから継承した部分クラスCから継承した部分 3.5 C B (multiple inheritance) Java (C ++ ) Java (single inheritance) Java C ++ Java 3.33 // class AmphibiousCycle extends Car, Boat { // speed drive() class Car { // double speed; // km/h void drive() { // class Boat { // double speed; // knot : 1knot = 1852m/h void drive() { // 2 (

177 3.4 ( ) 163 ) 乗り物 drive() 自動車 船 drive() drive() 水陸両用車 drive() 3.6 C ++ ( ) Java ( ) 2 A C C A A C ( ) (a),(b),(c) (a) (b) (c) C + c : int C + c : int B + b : int C + c : int B + b : int A B A A D + a : int + b : int + a : int + a : int + d : int

178 164 3 Java II A クラスのインスタンスクラスの情報 + x : double + y : double + length() : double B + w : double + getweight() : double C + c : java.color + getcolor() : java.color クラス の情報 Object A Object A Object Human Student Human 3.5 A, B, C C Object Object java.lang.object java.lang Object Object public boolean equals( Object obj ) protected Object clone() public String tostring() Object Object ( ) C tostring() package section0304; 3.34 ObjectExample.tex (Object )

179 3.4 ( ) 165 public class ObjectExample { C a = new C( 100 ); C b = a; C c = new C( 100 ); System.out.println("a: " + a.tostring() ); System.out.println("b: " + b.tostring() ); System.out.println("c: " + c.tostring() ); System.out.println( "a.equals(b): " + a.equals( b ) ); System.out.println( "a.equals(c): " + a.equals( c ) ); class C { int value; C( int value ) { this.value = value; tostring() (^^;) ( ) JVM clone() Human Object Object 3.26 noda hasiguchi tostring() equals() ( ) Object 3.35 ArrayIsObject.java ( Object ) package section0304; import java.util.arrays; public class ArrayIsObject { int[] a = { 1, 2, 3 ; int[] b = { 1, 2, 3 ; System.out.println( "a: " + a.tostring() ); // System.out.println( "a == b : " + ( a == b ) ); // a b System.out.println( "a.equals(b) : " + a.equals( b ) ); // a b System.out.println( "Arrays.equals(a, b) : " + Arrays.equals( a, b) ); // a b a b

180 166 3 Java II equals == Arrays equals == equals() == ( ) equals() StringIsObject.java ( == equals() ) package section0304; public class StringIsObject { String a = "abcde"; String b = "abcde"; String c = "abc"; c += "de"; System.out.println( "a == b : " + ( a == b ) ); System.out.println( "a.equals(b) : " + a.equals( b ) ); System.out.println( "a == c : " + ( a == c ) ); System.out.println( "a.equals(c) : " + a.equals( c ) ); String a = "abcde"; Sting b = "abcde"; a b WeightedPoint ColoredWeightedPoint WeightedPoint print() 3.37 PointExample4.tex ( ) package section0304; import javafx.scene.paint.color; // javafx.scene.paint Color public class PointExample4 { ColoredWeightedPoint p = new ColoredWeightedPoint(1.0, 2.0, 3.0, Color.RED ); p.print();

181 3.4 ( ) ColoredWeightedPoint.java ( ) package section0304; import javafx.scene.paint.color; public class ColoredWeightedPoint extends WeightedPoint { private Color color; public ColoredWeightedPoint( double x, double y, double w, Color color ) { super( x, y, w ); this.color = public void print() { System.out.printf( "(%f, %f), w=%f:c=%s%n", this.getx(), this.gety(), this.getweight(), this.color.tostring() ); p.print(); ColoredWeightedPoint print() WeightedPoint print() ColoredWeightedPoint 3 UML print() Point WeightedPoint - x : double - y : double - ORIGIN : Point {final + setx( x : double ) : void + sety( y : double ) : void + getx( ) : double + gety( ) : double + print( ) : void + length( ) : double + distance( p : Point ) : double + distance( p : Point, q : Point ) : double + centroid( p : Point, q : Point ) : Point <<constructor>> + Point( x : double, y : double ) + public # protected ~ package private - private 可視性 - weight : double + getweight() : double + print( ) : void + centroid( WeightedPoint ) : WeightedPoint <<constructor>> + WeightedPoint( x : double, y : double, w : double ) + WeightedPoint( p : WeightedPoint ) - color : javafx.scene.paint.color ColoredWeightedPoint + print( ): void <<constructor>> + ColoredWeightedPoint( x : double, y : double, w : double, color : Color ) 3.7 UML SubClass method()

182 168 3 Java II 3.39 package section0304; public class OverrideExample2 { SubClass a = new SubClass(); a.method(); // class SuperClass { public void method() { System.out.println( "SuperClass.method()" ); // class SubClass extends SuperClass void method() { System.out.println( "SubClass.method()" ); OverrideExample2.java ( ) public package-private ( package-private public ) Object tostring() equals() public clone() protected tostring() Object ( ) Point tostring() Point print() tostring print() package p1; import p2.b; public class C { A a = new A(); a.method();

183 3.4 ( ) 169 System.out.println( a.x ); System.out.println( a.b[0] ); System.out.println( a.y ); System.out.println( a.z ); class A extends B { public int x = 100; int[] b = {1,2,3; void method() { A a = new A(); System.out.println( a.z ); package p2; public class B { private int y = 123; protected double z = 1.23; super this this.x x this.method() method() this( ) super super.x x super.method() method() super( ) ( ) (super.x == this.x ) super.x 3.40 package section0304; public class SuperExample { SubA b = new SubA( 10 ); b.print(); b.print2(); SuperExample.java (supar. )

184 170 3 Java II class SuperA { int x; void print() { System.out.println( "SuperA:" + x ); class SubA extends SuperA { SubA( int x ) { this.x = void print() { System.out.println( "SubA:" + x ); void print2() { super.print(); print2() A print() super.print() super. print() super.super.print() final final final final final ( ) final String System Math final String final final

185 3.4 ( ) FinalParameter.java ( final) package section0304; public class FinalParameter { String x = "pen"; String y = "pineapple"; System.out.printf( "%s + %s = %s%n", x, y, add( x, y ) ); x = "apple"; System.out.printf( "%s + %s = %s%n", x, y, add( x, y ) ); static String add( String a, String b ) { String c = a + "." + b; b = "strawberry"; return c; final static String add(final String a, final String b){ b="strawberry"; final final Point q q = new Point(0,0); final 8 p.print(); 3.42 FinalExample.java (final ) package section0304; import section0302.point; public class FinalExample { final Point p = new Point(1,2); // p p.setx( 0 ); p.sety( 0 ); p.print(); // final Point q = new Point(1,2); q = new Point(0,0); // q.print();

186 172 3 Java II final 1 ( ) final int x = 123; double y = x; double x = 123.5; int y = x; double x = 123.5; int y = (int) x; y 3.43 package section0304; public class OverrideExample3 { SubC e = new SubC(); System.out.println( "c=" + e.c ); // System.out.println( ((SuperC) e).c ); e.print(); // ((SuperC) e).print(); e.print2(); // ((SuperC) e).print2(); class SuperC { int c = 1; void print() { System.out.println( "SuperC.print()" ); class SubC extends SuperC { int c = void print() { System.out.println( "SubC.print()" ); void print2() { System.out.println( "SubC.print2()" ); OverrideExample3.java ( ) SubC e c 2 print() print2() print() // e (SuperC) SuperC

187 3.4 ( ) 173 SuperC e ~ c : int = 1 ~ print( ) : void SubC ~ c : int = 2 ~ print( ) : void ~ print2( ) : void SubC 型インスタンス int c = 1 void print( ) int c = 2 void print2( ) オーバーライドされていないオーバーライドされているクラスSuperCから継承した部分 3.8 print2() 3.8 print() 2 ( ) SuperC e SubC ( print() ) e SuperC ((SuperC) e) e SuperC print2() ( ) SubC.print() e print() 2 ((SuperC) e).c 1 c 2 1 ( ) 2 e.c SubC c ((SuperC) e).c c ( super() )

188 174 3 Java II double x = 123; class A extends B A a = new B(); B b = new A(); double x = 123; ( ) B A a = new B(); ( 3.8 ) A A a = new B(); ( ) A ( 3.9 ) B b = new A(); B b = new A(); B b = new A(); b A b B a b B A a = new B( ); B b = new A( ); A B 型インスタンス B 型インスタンス この部分の情報が無い! A 型インスタンス A 型インスタンス 3.9 class A extends B ( 3.9 ) A a = new A(); // B b = (B) a; // b A c = b; // 3 ( ) b (?) A long l = 123L; int i = (int) l; long int ( )

189 3.5 ( ) A c = (A) b; c a ( ) instanceof ( ) instanceof boolean instanceof true 3.44 InstanceOfExample.java ( ) package section0304; import section0302.point; import javafx.scene.paint.color; public class InstanceOfExample { ColoredWeightedPoint cp = new ColoredWeightedPoint( 1.0, 2.0, 10.0, Color.RED ); WeightedPoint wp = new WeightedPoint( 0.0, 0.0, 1.0 ); Point p = new WeightedPoint( -1.0, -2.0, 0.0) ; // System.out.println( "(1) " + (cp instanceof ColoredWeightedPoint) ); System.out.println( "(2) " + (cp instanceof WeightedPoint) ); System.out.println( "(3) " + (cp instanceof Point) ); System.out.println( "(4) " + (wp instanceof ColoredWeightedPoint) ); // false System.out.println( "(5) " + (wp instanceof WeightedPoint) ); System.out.println( "(6) " + (wp instanceof Point) ); System.out.println( "(7) " + (p instanceof WeightedPoint) ); // true System.out.println( "(8) " + (p instanceof Point) ); C c = new A(); Object 2. B b = new C(); 3. Object obj = new A(); C 4. A a = new Object(); B 5. A a = new A(); if( a instanceof A ) { B b = a; 6. C c = new C(); if( c instanceof C ) { B b = c; A 7. A a = new A(); if( a instanceof C ) { B b = a; 3.5 ( ) (Polymorphism) (Monomorphism) 1 Point WeightedPoint

190 176 3 Java II ColoredWeightedPoint print() 3.45 PolymorphismExample.java ( (?)) package section0305; public class PolymorphismExample { Shape[] shapes = { new Circle( 1.2 ), // new Square( 1.5, 2.4 ), // new Trapezoid( 1.2, 3.0, 2.5 ) // ; for( Shape shape : shapes ) { shape.printarea(); class Shape { // String name; // double getarea() { // return 0; void printarea() { System.out.println( this.name + " " + this.getarea() ); class Circle extends Shape { // double radius; Circle( double radius ) { this.name = " "; this.radius = double getarea() { return radius * radius * Math.PI; class Square extends Shape { // double height; double width; Square( double height, double width ) { this.name = " "; this.height = height; this.width = double getarea() { return height * width; class Trapezoid extends Shape { // double upper; double lower;

191 double height; Trapezoid( double upper, double lower, double height ) { this.name = " "; this.upper = upper; this.lower = lower; this.height = double getarea() { return ( upper + lower ) * height / 2; ( ) (Dinamic binding) 3.6 Java 1 (algorithm error) (syntax error) (execution error) Java (scan.nextint()) JVM (Java Virtual Machine) (Exception) (Exception) Java (Exception) (throw ) catch catch catch

192 178 3 Java II ( ) 3.46 DivideZeroExample.java ( ) package section0306; public class DivideZeroExample { int x = 0; int y = 10; int z = y / x; System.out.printf( "%d / %d = %d%n", y, x, z ); Exception in thread "main" java.lang.arithmeticexception: / by zero at section0306.dividezeroexample.main(dividezeroexample.java:6) main java.lang.arithmeticexception section0306 DivideZeroExample.java main (DivideZeroExample.java 6 ) (single thread) 1 main Java (multi thread) 3.47 package section0306; public class OutOfBoundExample { int[] array = new int[10]; for(int i=1; i<=array.length; i++) { array[i] = i; for(int x : array) { System.out.print( x + " " ); System.out.println(); OutOfBoundExample.java ( ) Exception in thread "main" java.lang.arrayindexoutofboundsexception: 10 at section0306.outofboundexample.main(outofboundexample.java:6) 6 java.lang.arrayindexoutofboundsexception java.lang ArrayIndexOutOfBoundsException

193 Java JVM Exception (catch ) Exception java.lang.exception java.lang.error ( Error ) java.lang.object java.lang.throwable java.lang.exception java.lang.error java.io.ioexception java.lang.runtimeexception java.io.filenotfoundexception java.lang.arithmeticexception java.lang.indexoutofboundsexception java.lang.nullpointerexception java.lang.arrayindexoutofboundsexception 3.10 Exception Error java.lang.outofmemoryerror java.lang.stackoverflowerror Error ( ) Exception 2 java.lang.runtimeexception ArithmeticException ArrayIndexOutOfBoundsException (catch ) FileNotFoundException ( )

194 180 3 Java II NullPointerException (NullPointerException ) String str1 = ""; System.out.println( "str1.length = " + str1.length() ); String str2 = null; System.out.println( "str2.length = " + str2.length() ); try catch finally (stack trace) 3.48 ( ) DivideZeroExample.java ( ) package section0306; public class DivideZeroExample { int x = 0; int y = 10; try { int z = y / x; System.out.printf( "%d / %d = %d%n", y, x, z ); catch( Exception e ) { e.printstacktrace(); try try { 6 9 try try catch catch( ) { 9 11 catch catch 2 try catch try { // catch catch( Exception e ) { try catch catch (?)

195 Exception Exception catch ( ) Exception printstacktrace() 3.49 ( ) DivideZeroExample.java package section0306; public class DivideZeroExample { int x = 0; int y = 10; try { int z = y / x; System.out.printf( " %d / %d = %d%n", y, x, z ); catch( ArithmeticException e ) { System.err.println( " 0 " ); System.err.println( " " ); (?) ArithmeticException 3.50 ( ) OutOfBoundExample.java package section0306; import java.util.arrays; public class OutOfBoundExample { int[] array = new int[10]; try { for(int i=1; i<=array.length; i++) { array[i] = i; catch( ArrayIndexOutOfBoundsException e ) { System.err.println( " " ); System.out.println( Arrays.toString( array ) ); ArrayIndexOutOfBoundsException catch (^^;) try catch Java 7 catch 3.51 ( ) DivideZeroExample.java

196 182 3 Java II package section0306; public class DivideZeroExample { int x = 0; int y = 10; try { int z = y / x; System.out.printf( " %d / %d = %d%n", y, x, z ); catch( ArithmeticException e ) { System.err.println( " 0 " ); System.err.println( " " ); catch( Exception e ) { System.err.println( " " ); System.err.println( e ); 2 catch ArithmeticException 2 Exception 2 catch catch catch ArithmeticException Exception ArithmeticException Exception catch ArithmeticException catch catch System.out.println( e ); e.printstacktrace() 3.52 TwoCatchExample.java ( ) package section0306; public class TwoCatchExample { int[] array = new int[5]; int x = (int)(math.random() * 10); try { array[x] = 10 / x; System.out.printf( " %d %d%n", x, array[x] ); catch( ArithmeticException e ) { System.err.println( " " ); System.err.println( e ); catch( ArrayIndexOutOfBoundsException e ) { System.err.println( " " ); System.err.println( e ); catch Java 7 catch

197 ( ) TwoCatchExample.java package section0306; public class TwoCatchExample { int[] array = new int[5]; int x = (int)(math.random() * 10); try { array[x] = 10 / x; System.out.printf( " %d %d%n", x, array[x] ); catch( ArithmeticException ArrayIndexOutOfBoundsException e ) { System.err.println( " " ); System.err.println( e ); ( ) System.err.println System.out ( ) System.err Eclipse System.out System.err (redirect) ( ) 3.54 RedirectExample.java ( ) package section0306; import java.io.filenotfoundexception; import java.io.printstream; public class RedirectExample { // PrintStream defaultsystemout = System.out; PrintStream defaultsystemerr = System.err; // try { // out err System.setOut( new PrintStream("src/section0306/output.txt") ); System.setErr( new PrintStream("src/section0306/error.txt") ); catch (FileNotFoundException e) { e.printstacktrace(); for(int i=-10; i<10; i++) { try { System.out.println( i + ":" + 10/i ); catch( ArithmeticException e ) { System.err.println( i + ":" + " " ); // System.setOut( defaultsystemout ); System.setErr( defaultsystemerr ); System.out.println( " " );

198 184 3 Java II try catch try catch finally finally finally catch finally 3.55 FinallyExample.java ( finally ) package section0306; import java.io.file; import java.io.filenotfoundexception; import java.util.scanner; public class FinallyExample { Scanner scan = null; try { scan = new Scanner( new File( "src/section0306/input.txt" ) ); while( scan.hasnext() ) { System.out.println( scan.nextline() ); // scan.close(); // return; catch( FileNotFoundException e ) { System.out.println( " " ); finally { if( scan!= null ) { System.out.println( "finally " ); scan.close(); 3 FileNotFoundException FileNotFoundException 3 ( ) scan.close() 13 scan.close() finally finally ( ) ( finally )

199 (^^;) finally ( 14 return ) Exception 3.56 MyExceptionExample.java ( ) package section0306; import java.util.inputmismatchexception; import java.util.scanner; public class MyExceptionExample { // Scanner Scanner scan = new Scanner( System.in ); int n = 0; // 10 while( true ) { try { System.out.print( "10 " ); // inputint n = inputint( scan ); // break; catch( NoWithinRangeException e ) { System.out.println( e.tostring() ); System.out.println(); System.out.println( " " + n ); // Scanner [1,9] static int inputint( Scanner scan ) throws NoWithinRangeException { int n = scan.nextint(); if( n <= 0 n >= 10 ) { throw new NoWithinRangeException(); return class NoWithinRangeException extends Exception { NoWithinRangeException() { super( "\n!" ); NoWithinRangeException Exception Exception super Exception

200 186 3 Java II \n main inputint( scan ) inputint 10 NoWithinRangeException ( main ) try catch throws throw throws MyException1, MyException2 main catch inputint catch main catch MyExceptionExample.java inputint 3.7 Scanner Scanner Scanner Java 5.0 C scanf() Scanner java.util ( ) java.util import Scanner ( ) next nextline 3.57 package section0307; import java.util.scanner; public class ScannerExample { System.out.print( " " ); Scanner scan = new Scanner( System.in ); int n = scan.nextint(); System.out.println( " " + n ); scan.close(); ScannerExample.java ( )

201 3.7 Scanner Scanner Scanner(InputStream source[, String charsetname]) [throws IllegalArgumentException] (System.in) Scanner(File source[, String charsetname]) throws FileNotFoundException[, IllegalArgumentException] Scanner(Path source[, String charsetname]) throws IOException[, IllegalArgumentException] Scanner(Readable source) Readable Scanner(ReadableByteChannel source[, String charsetname]) [throws IllegalArgumentException] Scanner(String source) Scanner void close() Pattern delimiter() boolean hasnext([pattern pattern j String pattern]) true boolean hasnextint([int radix]) int true boolean hasnextline() true String next([pattern pattern j String pattern]) int nextint([int radix]) int String nextline() Scanner skip(pattern pattern j String pattern) Scanner usedelimiter(pattern pattern j String pattern) Scanner useradix(int radix) Scanner ( System.in) scan nextint close Eclipse next next ( delimiter) ( )

202 188 3 Java II 3.58 ScannerExample2.java (next) package section0307; import java.util.scanner; public class ScannerExample2 { Scanner scan = new Scanner( "abc def" ); System.out.println( "scan1 = " + scan.next() ); System.out.println( "scan2 = " + scan.next() ); scan.close(); nextline 3.59 ScannerExample3.java (nextline) package section0307; import java.util.scanner; public class ScannerExample3 { Scanner scan = new Scanner( "abc def" ); System.out.println( "scan1 = " + scan.nextline() ); scan.close(); 1 next() Scanner next() nextline() 3.60 ScannerExample4.java (Scanner ) package section0307; import java.util.scanner; public class ScannerExample4 { // String linecd = System.getProperty("line.separator"); Scanner scan = new Scanner( "abc"+ linecd +"def" ); System.out.println( "scan1 = " + scan.next() ); System.out.println( "scan2 = " + scan.nextline() ); scan.close(); System getproperties() next abc scan1 scan

203 3.7 Scanner 189 nextline next() nextint() nextline() scan2 scan.nextline(); 1 ( ) CSV CSV Comma-Separated Values,.csv Windows CSV Excel Excel CSV Java Scanner Scanner usedelimiter 3.61 DelimiterExample.java ( ) package section0307; import java.util.scanner; public class DelimiterExample { String text = "10 hours, 20 minutes, 30 seconds"; // String values = text.replaceall("[^0-9,]", ""); // Scanner scan = new Scanner(values); scan.usedelimiter( ", " + System.getProperty("line.separator") ); // int hours = scan.nextint(); int minutes = scan.nextint(); int seconds = scan.nextint(); scan.close(); System.out.printf("%2d:%2d:%2d%n", hours, minutes, seconds); String replaceall (Regular Expression) 0-9, ^ [ ] values 10,20,30 usedelimiter ( )

204 190 3 Java II DelimiterExample.java replaceall ( \\s*,\\s* ) Scanner findinline match MathResult group(int) ( ) 3.62 ScannerExample5.java ( ) package section0307; import java.util.scanner; import java.util.regex.matchresult; public class ScannerExample5 { Scanner scan = new Scanner( "Usain Bolt:100m:9.58sec" ); /* * \\w A-Z, a-z, 0-9, _ * * [ ]+ * \\d 0-9 * ( ) match */ scan.findinline( "([\\w ]+):(\\d+)m:([\\d]+.[\\d]+)sec" ); MatchResult result = scan.match(); scan.close(); // group 1 String name = result.group(1); int dist = Integer.valueOf(result.group(2)); double time = Double.valueOf(result.group(3)); System.out.println( name + " " + dist + " m " + time + " "); File Scanner Java Windows C:Yjava (MacOS ) workspace ( ) src bin.metadata

205 3.7 Scanner 191 Eclipse ( ) ( Eclipse ) 3.63 HelloJavaFromFile.java ( Duke) package section0307; import java.io.file; import java.io.filenotfoundexception; import java.util.scanner; public class HelloJavaFromFile { public static void main(string[] args) throws FileNotFoundException { // src section0307 hellojava.txt File file = new File( "src/section0307/hellojava.txt" ); Scanner scan = new Scanner( file ); String message = scan.nextline(); System.out.println( message ); scan.close(); hellojava.txt ( ) Duke 3.64 hellojava.txt ( ) File folder0 folder1 2 file1 folder2 file4 file2 file3 1. file1 file4../file4 2. file4 file1 folder1/file1 3. file1 file2 4. file1 file3 5. file3 file4

206 192 3 Java II Scanner(File) Scanner nextint() Scanner File File Scanner Scanner Java Java 5.0 FileReader BufferedReader InputStreamReader Scanner Scanner ( Scanner ) inputdata.txt /src/section0307 inputdata.txt inputdata.txt ( ) 3.66 FileScanner.java (Scanner ) package section0307; import java.io.file; import java.io.filenotfoundexception; import java.util.scanner; public class FileScanner { public static void main(string[] args) throws FileNotFoundException { Scanner scan = new Scanner( new File( "src/section0307/inputdata.txt" ) ); int x = scan.nextint(); int y = scan.nextint(); int z = x * y; System.out.printf( "%d * %d = %d %n", x, y, z ); double a = scan.nextdouble(); double b = scan.nextdouble(); double c = a * b; System.out.printf( "%f * %f = %f %n", a, b, c ); scan.close(); FileNotFoundException FileNotFoundException IOException (catch ) catch throw (throws FileNotFoundException)

207 Scanner Scanner close() Scanner ( ) nextint() nextlong() nextdouble() Scanner hasnext() hasnext() true next ( ) 3.67 ScannerReadFile.java (hasnext() ) package section0307; import java.io.file; import java.io.filenotfoundexception; import java.util.scanner; public class ScannerReadFile { try { Scanner scan = new Scanner( new File( "src/section0307/number.txt" ) ); int count = 0; while( scan.hasnext() ){ String str = scan.next(); count++; System.out.printf( "%2d %s%n", count, str ); scan.close(); catch(filenotfoundexception e) { System.out.println(" "); 3.8 Scanner Java (stream) ( 3.11 ) ( )

208 194 3 Java II キーボード 画面 入力ストリームプログラム出力ストリーム ファイル ファイル 3.11 java.io import ( 3.12 ) Writer Reader Output Input 4 抽象クラス java.io.writer バッファリングすることで書き込みを効率化 java.io.bufferedwriter 3 文字ストリームからバイトストリームへの橋渡し java.io.outputstreamwriter 4 文字ファイルへの書き込み簡易クラス java.io.filewriter 2 抽象クラス : バイト出力ストリームを表現する全てのクラスのスーパークラス java.io.outputstream java.io.filteroutputstream バッファリングされた出力ストリーム java.io.bufferedoutputstream 生のバイトストリームを書き込む際に使用 java.io.fileoutputstream FileInputStream / FileOutputStream FileInput(Output)Stream FileInput(Output)Stream File File FileNotFoundException read write read write IOException close

209 StreamExample01.java (FileOutputStream ) package section0308; import java.io.file; import java.io.fileinputstream; import java.io.filenotfoundexception; import java.io.fileoutputstream; import java.io.ioexception; public class StreamExample01 { // File file = new File( "src/section0308/file01.txt" ); String str = "abcdefg\n "; try { System.out.println( " " ); FileOutputStream fos = new FileOutputStream( file ); // fos.write( str.getbytes() ); fos.close(); // catch ( FileNotFoundException e ) { System.out.println( " " ); catch ( IOException e ) { System.out.println( " " ); // try { System.out.println( " " ); // byte[] bdata = new byte[(int) file.length()]; FileInputStream fis = new FileInputStream( file ); fis.read( bdata ); fis.close(); // // str = new String( bdata ); System.out.println( str ); catch ( FileNotFoundException e ) { System.out.println( " " ); catch ( IOException e ) { System.out.println( " " ); section0308 ( ) jpeg bitmap 3.69 package section0308; StreamExample02.java (FileOutputStream )

210 196 3 Java II import java.io.file; import java.io.fileinputstream; import java.io.filenotfoundexception; import java.io.fileoutputstream; import java.io.ioexception; public class StreamExample02 { File file = new File("src/section0308/doraemon.bmp"); File file2 = new File("src/section0308/copy.bmp"); byte[] bdata = null; // try { System.out.println(" "); bdata = new byte[(int)file.length()]; FileInputStream fis = new FileInputStream( file ); fis.read( bdata ); fis.close(); catch (FileNotFoundException e) { System.out.println( " "); catch (IOException e) { System.out.println(" "); // try { System.out.println(" "); FileOutputStream fos = new FileOutputStream( file2 ); fos.write( bdata ); fos.close(); catch (FileNotFoundException e) { System.out.println( " "); catch (IOException e) { System.out.println(" "); FileReader / FileWriter Reader / Writer ( Scanner ) FileReader FileWriter Reader / Writer FileWriter write FileReader read read 1 ( ) 3.70 package section0308; import java.io.file; import java.io.filenotfoundexception; StreamExample03.java (FileWriter )

211 import java.io.filereader; import java.io.filewriter; import java.io.ioexception; public class StreamExample03 { File file = new File("src/section0308/file01.txt"); String str = "abcdefg\n "; // try { System.out.println(" "); FileWriter fw = new FileWriter( file ); fw.write( str ); fw.close(); catch (IOException e) { System.out.println(" "); // try { System.out.println(" "); str = ""; FileReader fr = new FileReader( file ); int c; while( (c = fr.read())!=-1 ) { str += (char) c; fr.close(); System.out.println( str ); catch (FileNotFoundException e) { System.out.println( " "); catch (IOException e) { System.out.println(" "); BufferedReader / BufferedWriter abc a b c OS ( ) ( ) FileReader BufferedReader / BufferedWriter BufferedWriter(Reader) FileWriter(Reader) writer newline readline readline null

212 198 3 Java II close 3.71 StreamExample04.java (BufferedWriter ) package section0308; import java.io.bufferedreader; import java.io.bufferedwriter; import java.io.file; import java.io.filenotfoundexception; import java.io.filereader; import java.io.filewriter; import java.io.ioexception; public class StreamExample04 { File file = new File("src/section0308/file01.txt"); String str = "abcdefg\n "; System.out.println(" "); // try { BufferedWriter bw = new BufferedWriter( new FileWriter( file )); bw.write( str ); bw.newline(); bw.close(); catch (IOException e) { System.out.println(" "); System.out.println(" "); // try { BufferedReader br = new BufferedReader( new FileReader( file )); String line; while( (line = br.readline())!= null ) { System.out.println( line ); br.close(); catch (FileNotFoundException e) { System.out.println( " "); catch (IOException e) { System.out.println(" "); InputStreamReader / OutputStreamWriter InputStreamReader(Writer) Java UNICODE ISO2022JP (JIS ) SJIS ( JIS ) EUC JP ( UNIX ) EUC JP SJIS Eclipse 3.72 StreamExample05.java (OutputStreamWriter )

213 package section0308; import java.io.bufferedreader; import java.io.bufferedwriter; import java.io.file; import java.io.fileinputstream; import java.io.filenotfoundexception; import java.io.fileoutputstream; import java.io.ioexception; import java.io.inputstreamreader; import java.io.outputstreamwriter; public class StreamExample05 { File file = new File( "src/section0308/file02.txt" ); String str = "abcdefg\n "; System.out.println( " " ); // EUC try { BufferedWriter bw = new BufferedWriter( new OutputStreamWriter( new FileOutputStream( file ),"EUC_JP") ); bw.write( str ); bw.newline(); bw.close(); catch ( IOException e ) { System.out.println( " " ); System.out.println( " " ); // "SJIS" try { BufferedReader br = new BufferedReader( new InputStreamReader( new FileInputStream( file ), "SJIS") ); String line; while( (line = br.readline())!= null ) { System.out.println( line ); br.close(); catch (FileNotFoundException e) { System.out.println( " " ); catch (IOException e) { System.out.println( " " ); Java Excel Mathematica Java Java Excel Java Excel Excel Mathematica Mathematica Java Mathematica

214 200 3 Java II CSV csv CSV Comma Separated Values Excel Excel Mathematica Import CSV 3.73 CSV Example.java (CSV ) package section0308; import java.io.bufferedwriter; import java.io.filewriter; import java.io.ioexception; public class CSV_Example { public static void main(string[] args) throws IOException { // BufferedWriter bw = new BufferedWriter(new FileWriter("src/section0308/curve.csv")); bw.write(", Sin( )/ "); bw.newline(); // [0.1, 30.0] 0.1 for(int i=1; i<=300; i++) { double x = i / 10.0; bw.write( String.valueOf(x) ); bw.write(","); bw.write( String.valueOf(func(x)) ); bw.newline(); bw.close(); System.out.println(" "); static double func(double x) { return Math.sin( x )/x; Eclipse Excel section0308 curve.csv Excel Excel Mathematica Mathematica data = Import[ ] ListPlot[data] [ ] URL 3.9 import Java java.util ArrayList java.util.arraylist list = new java.util.arraylist();

215 3.9 import 201 import ( ) import java.util.arraylist; ArrayList ArrayList list = new ArrayList(); import import import package java.util.arraylist java util ArrayList import (on demand import) java.util 3 import java.util.arraylist; import java.util.linkedlist; import java.util.hashmap; import java.util.*; ( ) import java.awt.canvas; import java.awt.color; import java.awt.event.actionevent; import java.awt.event.mouseaapter; import java.awt.*; import java.awt.event.*; import java.awt import import ( 3.74 ) 3.74 ImportExamaple.java ( ) package section0309; import section0309.sub1.a; public class ImportExamaple { A.print(); // import section0309.sub2.a.print(); //

216 202 3 Java II package section0309.sub1; public class A { public static void print() { System.out.println( "section0309.sub1.a "); package section0309.sub2; public class A { public static void print() { System.out.println( "section0309.sub2.a "); java.lang java.lang Java System.out.println System Object Math String Thread import System.out.println Math.cos java.lang.system.out.println java.lang.math.cos Java 5.0 (static import) java.lang.math Math import 3.75 StaticImportExample.java ( ) package section0309; import static java.lang.math.pi; import static java.lang.math.pow; public class StaticImportExample { double radius = 1.2; System.out.println( " " + radius + " " + pow(radius,2) * PI );

217 ( ) ( ) (abstract class) (concrete class) abstract (abstract method) 3.76 AbstractClass.java ( (?)) package section0310; public class AbstractClass { Shape[] shapes = { new Circle( 1.2 ), // new Square( 1.5, 2.4 ), // new Trapezoid( 1.2, 3.0, 2.5 ) // ; for( Shape shape : shapes ) { shape.printarea(); // abstract class Shape { String name; // Shape( String name ) { // this.name = name; void printarea() { System.out.println( this.name + " " + this.getarea() );

218 204 3 Java II // abstract double getarea(); // class Circle extends Shape { double radius; Circle( double radius ) { super( " " ); this.radius = double getarea() { // return radius * radius * Math.PI; // class Square extends Shape { double height; double width; Square( double height, double width ) { super( " " ); this.height = height; this.width = double getarea() { // return height * width; // class Trapezoid extends Shape { double upper; double lower; double height; Trapezoid( double upper, double lower, double height ) { super( " " ); this.upper = upper; this.lower = lower; this.height = double getarea() { // return ( upper + lower ) * height / 2; Shape Shape 0 Shape getarea() abstract ( abstract double getarea(); ) ( ) abstract int calc( int x, int

219 y ); ( ) Shape double getarea() super(" "); Shape this(); this() super() main shape shape.printarea(); Shape printarea getarea() (Telephone ) (Cellular) (FixedLinePhone) ( ) Telephone 抽象クラス 抽象メソッドは 名前を斜体で Cellular FixedLinePhone Java C ++ Java (interface) ( ) 3.77 InterfaceExample.java ( ) package section0310; public class InterfaceExample { Dog pochi = new Dog( " " ); // Dog peace = new HearingDog( " " ); // Dog hope = new RescureDog( " " ); // Dog lucky = new RescureHearingDog( " " ); // Dog[] mydogs = { pochi, peace, hope, lucky ; for(dog dog : mydogs) { dog.print(); System.out.println();

220 206 3 Java II // Rescurable[] rescurabledogs = RescureDog.selectRescureDog( mydogs ); for(rescurable dog : rescurabledogs) { dog.rescure(); // ( ) class Dog { String name; Dog( String name ) { this.name = name; void print() { System.out.printf( " %s %n", this.name ); // class HearingDog extends Dog implements Hearable { HearingDog( String name ) { super( name void print() { System.out.printf( " %s %n", this.name public void hearing() { System.out.printf( " %s %n", this.name ); // class RescureDog extends Dog implements Rescurable { RescureDog( String name ) { super( name void print() { System.out.printf( " %s %n", this.name public void rescure() { System.out.printf( " %s %n", this.name ); // public static Rescurable[] selectrescuredog( Dog[] dogs) { Rescurable[] selecteddog = new Rescurable[dogs.length]; int count = 0; for(dog dog : dogs) { if( dog instanceof Rescurable ) { selecteddog[count++] = (Rescurable) dog; Rescurable[] rescurabledogs = new Rescurable[count]; System.arraycopy(selectedDog, 0, rescurabledogs, 0, count);

221 return rescurabledogs; // class RescureHearingDog extends Dog implements Hearable, Rescurable { RescureHearingDog( String name ) { super( name void print() { System.out.printf( " %s %n", this.name public void rescure() { System.out.printf( " %s %n", this.name public void hearing() { System.out.printf( " %s %n", this.name ); // interface Hearable { void hearing(); // ( ) // interface Rescurable { void rescure(); // ( ) <<interface>> Hearable ~ hearing( ) : void Dog ~ name : String ~ print( ) : void <<interface>> Rescurable ~ rescue( ) : void HearingDog RescureDog RescureHearingDog 3.13 interface

222 208 3 Java II public package-private public public abstract public static final ( extends ) (extends) (implements) UML ( 3.13 ) implements class implements { RescureHearingDog 2 Hearable Rescurable false 3.78 InterfaceExample2.java ( instanceof) package section0310; public class InterfaceExample2 { B a = new A(); System.out.println("a instanceof A = " + (a instanceof A) ); System.out.println("a instanceof B = " + (a instanceof B) ); System.out.println("a instanceof C = " + (a instanceof C) ); A b = new A(); System.out.println("b instanceof A = " + (b instanceof A) ); System.out.println("b instanceof B = " + (b instanceof B) ); System.out.println("b instanceof C = " + (b instanceof C) ); B c = new B(); System.out.println("c instanceof A = " + (c instanceof A) ); System.out.println("c instanceof B = " + (c instanceof B) ); System.out.println("c instanceof C = " + (c instanceof C) ); C d = new A();

223 System.out.println("d instanceof A = " + (d instanceof A) ); System.out.println("d instanceof B = " + (d instanceof B) ); System.out.println("d instanceof C = " + (d instanceof C) ); class A extends B implements C { public void method() { System.out.println( "yahoo!" ); class B { final int CONST = 100; interface C { void method(); d C d A C method() B CONST ( main System.out.println( d.const ); System.out.println( ((A).d).const ); 100 ) d.method(); yahoo! Java 8 ( ) Java (Java 8 API ) ( ) 3.79 InterfaceExample3.java ( ) package section0310; public class InterfaceExample3 { // TestClass tc = new TestClass(); tc.hello(); // TestClass2 tc2 = new TestClass2(); tc2.hello(); // TestClass3 tc3 = new TestClass3();

224 210 3 Java II tc3.hello(); interface Interface1 { // // default default void hello() { System.out.println( "Hello interface1" ); interface Interface2 { // default void hello() { System.out.println( "Hello interface2" ); class TestClass implements Interface1 { class TestClass2 implements Interface1, Interface2 public void hello() { System.out.println( "Hello TestClass2" ); class TestClass3 implements Interface1, Interface2 { public void hello() { Interface1.super.hello(); static ( static ) 3.11 Java API Collection (generics) (type parameter) (generic type) (type parameter), (type variable) (parameterized type) (raw type) (actual type parameter) (bounded type parameter) (unbounded wildcard type) (upper bounded wildcard type) (lower bounded wildcard type) List<E> <E> List<String> List <String> <E extends Number> List<?> List<? extends Number> List<? super Number>

225 package section0311; public class BoxExample1 { Box1 ibox = new Box1( new Integer(123) ); int n = ((Integer) ibox.get()).intvalue(); System.out.println( n ); BoxExample1.java ( ) // Box1 dbox = new Box1( new Double(12.3) ); // double m = ((Integer) dbox.get()).doublevalue(); // System.out.println( m ); Box1 sbox = new Box1( "Hello" ); String hello = (String) sbox.get(); System.out.println( hello ); class Box1 { Object obj; Box1( Object obj ) { this.obj = obj; Object get() { return obj; Box1 int double String Object Object ( ) int Object Integer (wrapper class) ( ) new Integer(10) 10 Integer ibox String Object Box1 Object Object obj get() Object main int n Integer Integer int intvalue()

226 212 3 Java II double Double ( Object ) Object Double Integer (type safe) 3.81 BoxExample2.java ( ) package section0311; public class BoxExample2 { Box<Integer> ibox = new Box<Integer>( new Integer(123) ); int n = ((Integer) ibox.get()).intvalue(); System.out.println( n ); // Box<Double> dbox = new Box<Double>( new Double(12.3) ); // double m = ((Integer) dbox.get()).doublevalue(); // System.out.println( m ); Box<String> sbox = new Box<String>( "Hello" ); String hello = (String) sbox.get(); System.out.println( hello ); class Box<E> { E e; Box( E e ) { this.e = e; E get() { return e; Box < > 3.82 package section0311; public class BoxExample3 { Box<Integer> ibox = new Box<Integer>( 123 ); int n = ibox.get(); System.out.println( n ); Box<Double> dbox = new Box<Double>( 12.3 ); BoxExample3.java ( )

227 double m = dbox.get(); System.out.println( m ); Box<String> sbox = new Box<String>( "Hello" ); String hello = sbox.get(); System.out.println( hello ); Box<Integer> Integer int Integer ( double Double ) (Autoboxing) ( ) (Auto-Unboxing) ( ) Integer a = 123; int b = a; ( null) NullPointerException class Box<E> { E e; Box( E e ) { this.e = e; E get() { return e; 3.83 Box Box <E> E ( Element ) Box<Integer> E Integer Box<String> E String <E> (Object ) Box Eclipse ( Eclipse ) BoxExample3.java 3.84 BoxExample3.java ( ) package section0311; /* */ import section0311.box; /* */ public class BoxExample3 { /* */ /* 5 */ Box ibox = new Box(Integer.valueOf(123)); /* 6 */ int n = ((Integer)ibox.get()).intValue();

228 214 3 Java II /* 7 */ System.out.println(n); /* */ /* 9 */ Box dbox = new Box(Double.valueOf(12.3D)); /* 10 */ double m = ((Double)dbox.get()).doubleValue(); /* 11 */ System.out.println(m); /* */ /* 13 */ Box sbox = new Box("Hello"); /* 14 */ String hello = (String)sbox.get(); /* 15 */ System.out.println(hello); /* */ /* 17 */ /* */ Box class Box { Object e; Box( Object e ) { this.e = e; Object get() { return e; 3.85 Box Object [ 1] [ 2] [ 3] [ 4] [ 5] [ 6] = Box<int> box = E e = new E() = E[] e = new E[10] Object static static = static ( ) ( ) E T ( Type ) E (Element) T (Type) S K (Key) V (Value) package section0311;

229 public class CreateBoxExample Create<Integer> ci = new Create<Integer>(); Box<Integer> ibox = ci.makebox(100); // Integer i = ci.maket(); // Integer[] iarray = ci.makearray(10); class Create<T> { Box<T> makebox(t e) { return new Box<T>(e); /* T maket() { return new T(null); T[] makearray(int n) { return new T[n]; */ Box ( ) Box<T> makebox(t e) Box makebox(object e) T maket() Object Integer T[] makearray(int n) Object Integer Integer Object Integer Object ( ) ArrayStoreException 3.86 IntegersToObjects.java (Integer Object ) package section0311; import java.util.arrays; public class IntegersToObjects { Integer[] integers = {1, 2, 3; Object[] objects = integers; objects[0] = 1.23; System.out.println( Arrays.toString( objects ) ); String[] strings = {"a", "b", "c"; objects = strings; System.out.println( Arrays.toString( objects ) );

230 216 3 Java II Integer Object Box<Integer> Box<Object> package section0311; public class BoxExample4 { Box<Object> box = new Box<Object>(null); // box = new Box<Integer>( 100 ); // System.out.println( box.get() ); // box = new Box<String>( "Hello" ); System.out.println( box.get() ); Box<Integer> Box<String> Box<Object> (wildcard type) package section0311; public class BoxExample4 { Box<?> box = null; box = new Box<Integer>( 100 ); System.out.println( box.get() ); box = new Box<String>( "Hello" ); System.out.println( box.get() ); Box<?> 3.87 package section0311; public class IntegersToObjects3 { NBox<? extends Number> nbox = null; nbox = new NBox<Integer>( 100 ); System.out.println( nbox.get() ); nbox = new NBox<Double>( ); System.out.println( nbox.get() ); // nbox = new NBox<String>( "abc" ); class NBox<E extends Number> { E e; NBox( E e ) { this.e = e; E get() { return e; IntegersToObjects3.java ( )

231 Number Number ( Number ) Number int n = (Integer) nbox.get(); System.out.println( n ); Generic swap 3.88 GenericMethod.java (Generic method ) package section0311; import java.util.arrays; public class GenericMethod { String[] s = {"a", "b", "c"; swap(s,1,2); System.out.println( Arrays.toString( s ) ); Integer[] i = {1, 2, 3; swap(i,1,2); System.out.println( Arrays.toString( i ) ); Object[] o = {new Integer(10), "a", new Long(0); swap(o,1,2); System.out.println( Arrays.toString( o ) ); static <T> void swap(t[] array, int i, int j) { T temp = array[i]; array[i] = array[j]; array[j] = temp; ( void) swap<string>( s ); ( ) T[] merge(t[], T[]) GenericMethod.java

232 218 3 Java II (wrapper class) ( ) int x; int x byte short int long float double boolean char Byte Short Integer Long Float Double Boolean Character Integer.MAX_VALUE int Integer MAX_VALUE Integer ( ) public Integer static int MAX_VALUE int static int MIN_VALUE int 2 31 Integer(int) Integer Integer(String) Integer static int compare(int, int) int static int max(int, int) int static int min(int, int) int static int parseint(string) static Integer valueof(int) Integer static Integer valueof(string) Integer int compareto(integer) Integer boolean equals(object) Object int intvalue() int String tostring() [0, 1) ArrayList<Double> numbers RandomDoubles.java Math.random()

233 3.12 Java API IntegerExample.java (Integer ) package section0311; public class IntegerExample { Integer value1 = new Integer( 100 ); Integer value2 = new Integer( "100" ); System.out.println( value1 == value2? " ":" " ); System.out.println( value1.compareto( value2 ) == 0? " ":" " ); System.out.println( value1.equals( value2 )? " ":" " ); ArrayListExample.java list.add( 30 ) ArrayList<Integer> list.add( new Integer( 30 ) ) Java 5 Java (autoboxing) (autounboxing) int Integer list.add( new Integer(10) ) list.add( 10 ) OK ( ) int x = list.get(0).intvalue() Integer int x = array.get(0) OK ( ) Java Integer value2 = 100; 3.12 Java API API (Application Programming Interface) OS API OS Java JVM OS API Java OS API Java Java API Java API rt.jar zip Eclipse Java JRE rt.jar Java API

234 220 3 Java II Collection Collection Student[] students = new Student[100]; students.idnosort(); ( Student sort() Student.idNoSort( students ); ) Java API java.util Collection 3.14 <<interface>> Collection <<interface>> List <<interface>> Queue <<interface>> Set Stack ArrayList LinkedList PriorityQueue <<interface>> SortedSet HashSet 実装 : implements 継承 : extends <<interface>> NavigableSet LinkedHashSet TreeSet 3.14 Collection Collection 3 (List ) (Queue ) (Set ) ( ) ArrayList List

235 3.12 Java API ArrayList Collection Map SortedMap ArrayList List ArrayList ArrayList List ( ) Java 3.90 ArrayListExample.java (ArrayList ) package section0311; import java.util.list; import java.util.arraylist; import java.util.comparator; public class ArrayListExample { List<Integer> list = new ArrayList<Integer>(); // list.add( new Integer(10) ); // 10 list.add( new Integer("20") ); // Integer OK

236 222 3 Java II ArrayList<E > (E ) ArrayList() ArrayList(int) boolean add(e) void add(int, E) void clear() Object clone() E get(int) int indexof(object) boolean isempty() boolean remove(object) E remove(int) E set(int, E) int size() void sort(comparator<? super E>) Object[] toarray() 10 true list.add( 30 ); // int list.add( 2, 40 ); // list [2] 40 (30 ) System.out.println( "ArrayList " + list.size() ); System.out.println( list.tostring() ); list.sort( Comparator.naturalOrder() ); // System.out.println( list.tostring() ); list.remove(1); // array [1] ( ) System.out.println( list.tostring() ); ArrayList<Integer> ArrayList List list List ArrayList ArrayList<Point> points = new ArrayList<Point>(100); ArrayList ( ) add Arrays aslist 3.91 package section0312; import java.util.arraylist; import java.util.arrays; public class ArrayListExample2 { ArrayListExample2.java ( ArrayList )

237 3.12 Java API 223 // int Integer Integer[] intarray = { 10, 20, 30, 40 ; ArrayList<Integer> intlist = new ArrayList<Integer> (Arrays.asList( intarray ) ); intlist.add(2, 50); System.out.println( intlist.tostring() ); List<Integer> List<Double> List<Number> list.add( new Double(12.3) ) Comparable Comparator 3.90 Comparator.naturalOrder 2 Java 2 Comparable Comparator java.lang.comparable<t> int compareto(t) compareto(t) 1, 0, Point.java (Comparable ) package section0312; /** * 2 ( ) */ class Point implements Comparable<Point> { /** x */ double x; /** y */ double y; Point( double x, double y ) { this.x = x; this.y = y; /** public String tostring() { return String.format( "(%4.1f,%4.1f)", this.x, this.y ); /** * ( ) */ double dist() {

238 224 3 Java II return Math.sqrt( x*x + y*y ); /** * (-1,0,1 ) <br> * < -1,<br> * = 0,<br> * > 1 public int compareto(point other) { double thisdist = this.dist(); double otherdist = other.dist(); if( thisdist > otherdist ) return 1; else if( thisdist < otherdist ) return -1; else return 0; Point Arrays.sort package section0312; import java.util.arrays; public class ComparableExample { Point[] points = { new Point( 1, 3), new Point( 2, 2), new Point(-2, 1), new Point( 4, 0), new Point( 1,-1), new Point( 0, 3), new Point( 3, 2) ; Arrays.sort( points ); for(point point : points) { System.out.print( point.tostring() + " " ); System.out.println(); Point List Collections.sort package section0312; import java.util.arraylist; import java.util.arrays; import java.util.collections; import java.util.list; public class ComparableExample2 { List<Point> points = new ArrayList<Point>( Arrays.asList( new Point[]{ new Point( 1, 3), new Point( 2, 2), new Point(-2, 1), new Point( 4, 0), new Point( 1,-1), new Point( 0, 3), new Point( 3, 2) ) );

239 3.12 Java API 225 Collections.sort( points ); for(point point : points) { System.out.print( point.tostring() + " " ); System.out.println(); Comparable java.util.comparator<t> compare(t o1, T o2) static package section0312; import java.util.arrays; import java.util.comparator; public class ComparatorExample { Point[] points = { new Point( 1, 3), new Point( 2, 2), new Point(-2, 1), new Point( 4, 0), new Point( 1,-1), new Point( 0, 3), new Point( 3, 2) ; Arrays.sort( points, new PointComparator() ); for(point point : points) { System.out.print( point.tostring() + " " ); System.out.println(); class PointComparator implements Comparator<Point> public int compare(point p, Point q) { double pdist = p.dist(); double qdist = q.dist(); if( pdist > qdist ) return -1; else if( pdist < qdist ) return 1; else return 0; Point ( ) Comparator<Point> PointComparator ArrayListExample.java List sort() sort() Comparator Comparator.naturalOrder() Comparator static naturalorder() Comparable Comparator List Integer Integer Comparable ( Java 8 )

240 226 3 Java II ComparableExample2.java Collections.sort( points ); Comparator.naturalOrder() Comparator.reverseOrder() (String) (double) (double) 3 Person pienuts BodyMeasurement.java Comparator BodyComparator Array.sort( pienuts, new BodyComparator() ) Person[] pienuts = { new Person("Snoopy", 80.0, 15.5), new Person("Charlie", 140.0, 35.5), new Person("Linus", 140.0, 32.0), new Person("Sally", 135.0, 26.5), new Person("Lucy", 142.0, 30.5), new Person("Schroeder", 142.0, 31.0), new Person("Peppermint", 144.0, 33.5), new Person("Marcie", 135.0, 29.5) ; Comparator Java 8 Comparator (^_^;) 3.93 ShapesExample.java ( ) package section0311; import java.util.arraylist; import java.util.comparator; import java.util.list; public class ShapesExample { List<Shape> shapes = new ArrayList<Shape>(); shapes.add( new Circle( 1.2 ) ); shapes.add( new Square( 1.5, 2.4 ) ); shapes.add( new Trapezoid( 1.2, 3.0, 2.5 ) ); // shapes.sort( Comparator.comparing(Shape::getArea) ); for( Shape shape : shapes ) { shape.printarea();

241 3.12 Java API 227 // abstract class Shape { String name; // Shape( String name ) { // this.name = name; abstract double getarea(); // : void printarea() { // System.out.printf( "%s %8.5f%n", this.name, this.getarea() ); // class Circle extends Shape { double radius; Circle( double radius ) { super( " " ); this.radius = double getarea() { // return radius * radius * Math.PI; // : class Square extends Shape { double height; double width; Square( double height, double width ) { super( " " ); this.height = height; this.width = double getarea() { // return height * width; // : class Trapezoid extends Shape { double upper; double lower; double height; Trapezoid( double upper, double lower, double height ) { super( " " ); this.upper = upper; this.lower = lower; this.height = double getarea() { // return ( upper + lower ) * height / 2;

242 228 3 Java II LinkedList ArrayList List LinkedList ArrayList ( ) LinkedList ( ) ( 3.16 ) list list LinkedList ArrayList LinkedList 100 ArrayList 100 LinkedList 100 ArrayList 101 LinkedList ( 3.16 ) 3.94 LinkedListExample.java (LinkedList ) package section0311; import java.util.list; import java.util.linkedlist; import java.util.comparator; public class LinkedListExample { List<Integer> list = new LinkedList<Integer>(); list.add( new Integer(10) ); list.add( new Integer("20") ); list.add( 30 ); list.add( 2, 40 );

243 3.12 Java API 229 System.out.println( "LinkedList " + list.size() ); System.out.println( list.tostring() ); list.sort( Comparator.naturalOrder() ); System.out.println( list.tostring() ); list.remove(1); System.out.println( list.tostring() ); LinkedList ArrayList List ArrayList LinkedList [0] Stack Queue Stackx ( ) Queue ( ) Stack LIFO (Last In First Out: ) Queue FIFO (First In First Out: ) ( 3.17 ) Stack Queue 4 Stack Queue Stack Queue Java Stack List Queue List Queue LinkedList PriorityQueue ( 3.14 ) LinkedList List Queue PriorityQueue Comparator ( ) Stack Queue

244 230 3 Java II Stack<E > Queue<E > E peek() E pop() E push(e) E peek() E poll() boolean offer(e) Stack Queue 3.95 StackQueue.java (Stack Queue ) package section0311; import java.util.linkedlist; import java.util.queue; import java.util.stack; public class StackQueue { Stack<Integer> stack = new Stack<Integer>(); stack.push( 100 ); // stack.push( 200 ); stack.push( 300 ); stack.push( 400 ); System.out.println( "Stack " + stack.capacity() ); System.out.println( " " + stack.size() ); System.out.println( stack.tostring() ); stack.pop(); System.out.println( "Stack " ); System.out.println( stack.tostring() ); stack.push( 500 ); System.out.println( "Stack 500 " ); System.out.println( stack.tostring() ); // LinkedList Queue Queue<Integer> queue = new LinkedList<Integer>(); queue.offer( 100 ); // queue.offer( 200 ); queue.offer( 300 ); queue.offer( 400 ); System.out.println( "Queue " + ((LinkedList<Integer>) queue).size() ); System.out.println( " " + queue.size() ); System.out.println( queue.tostring() ); queue.poll(); System.out.println( "Queue " ); System.out.println( queue.tostring() ); queue.offer( 500 ); System.out.println( "Queue 500 " ); System.out.println( queue.tostring() );

245 3.12 Java API Java LinkedList LinkedList Comparator StudentList() void add(string) void add(int, String, Date, double) void add(student) StudentCell find(int) boolean delete(int) true void print(): ( ) studentslist: package public StudentListExample main StudentList StudentCell StudentList Student ,, 1980,11,26, ,, 1982,1,25, ,, 1983,6,17, ,, 1983,8,30, ,, 1982,12,24, ,, 1978,11,7, ,, 1977,1,11, ,, 1970,11,17, ,, 1972,1,10, ,, 1974,9,2, ,, 1980,11,18, ,, 1979,7,2, ,, 1979,2,20, ,, 1976,5,17, ,, 1971,7,24, ,, 1972,10,9, ,, 1973,12,8, ,, 1977,1,31, , \UTF{5F45, 1974,7,9, students.txt ( ):src/section StudentListExample.java (main )

246 232 3 Java II package section0311; import java.io.filenotfoundexception; public class StudentListExample { public static void main(string[] args) throws FileNotFoundException { StudentList slist = new StudentList(); slist.add( "src/section0312/students.txt" ); slist.add( , " ", new Date(1972,8,18), ); slist.add( , " ", new Date(1972,11,13), ); slist.print(); System.out.println(); // slist.add( , " ", new Date(1972,8,18), ); // slist.delete( ); // " " slist.delete( ); // " " slist.delete( ); // " \UTF{5F45 " slist.delete( ); // " " slist.print(); 3.98 Student.java ( ) package section0311; /** 1.0 */ class Student { /** */ int idno; /** */ String name; /** {@link Date */ Date birthday; /** */ double height; /** * idno name birthday {@link Date height */ Student( int idno, String name, Date birthday, double height ) { this.idno = idno; this.name = name; this.birthday = birthday; this.height = height; /** * csv csvtext csv <br> *,,,,,

247 3.12 Java API 233 */ static Student makestudent( String csvtext ) { String[] term = csvtext.split(",", 0); int idno = Integer.parseInt( term[0].trim() ); String name = term[1].trim(); Date birthday = new Date( Integer.parseInt( term[2].trim() ), Integer.parseInt( term[3].trim() ), Integer.parseInt( term[4].trim() ) ); double height = Double.parseDouble( term[5].trim() ); return new Student( idno, name, birthday, height ); /** * other ${\1,0,1\$ */ public int compareto( Student other ) { if( this.idno < other.idno ) return -1; else if( this.idno == other.idno ) return 0; else return 1; /** * */ void print() { System.out.printf( "%d %-6s (%s) %5.1f%n", idno, name, birthday.tostring(), height ); 3.99 package section0311; /** 1.0 */ class Date { /** */ int year; /** */ int month; /** */ int day; /** * year month day */ Date( int year, int month, int day ) { this.year = year; this.month = month; this.day = day; Date.java ( )

248 234 3 Java II /** * */ public String tostring() { return String.format( "%4d/%02d/%02d", year, month, day ); StudentCell.java ( ) package section0311; /** * {@link StudentList 1.0 */ class StudentCell { /** */ Student student; /** */ StudentCell precell; /** */ StudentCell nextcell; /** * student */ StudentCell( Student student ) { this.student = student; precell = null; nextcell = null; /** other ${\1,0,1\$ */ public int compareto( StudentCell other ) { return (this.student).compareto( other.student ); package section0311; import java.io.file; import java.io.filenotfoundexception; import java.util.scanner; /** 1.0 */ class StudentList { /** */ StudentCell firstcell; // StudentList.java ( )

249 3.12 Java API 235 /** */ StudentCell lastcell; // /** */ StudentList() { this.firstcell = null; this.lastcell = null; /** * filename csv <br> * {@link Student#makeStudent(String) Student.makeStudent FileNotFoundException */ void add( String filename ) throws FileNotFoundException { Scanner scan = new Scanner( new File( filename ) ); while( scan.hasnextline() ) { String csvtext = scan.nextline(); Student newstudent = Student.makeStudent( csvtext ); add( newstudent ); scan.close(); /** * <br> * add(student) idno name birthday Date height */ void add( int idno, String name, Date birthday, double height ) { add( new Student( idno, name, birthday, height ) ); /** * newstudent Student <br> * null */ void add( Student newstudent ) { StudentCell newcell = new StudentCell( newstudent ); // if( firstcell == null && lastcell == null ) { firstcell = newcell; lastcell = newcell; return; // StudentCell nextcell = firstcell; while( nextcell!= null ) { // switch( nextcell.compareto( newcell ) ) { case -1: // nextcell = nextcell.nextcell; break; case 0: // System.out.println( " ");

250 236 3 Java II newcell.student.print(); System.out.println(); return; case 1: // ( ) if( nextcell == firstcell ) { // newcell.nextcell = firstcell; firstcell.precell = newcell; firstcell = newcell; else { // StudentCell precell = nextcell.precell; // precell.nextcell = newcell; newcell.precell = precell; newcell.nextcell = nextcell; nextcell.precell = newcell; return; // newcell.precell = lastcell; lastcell.nextcell = newcell; lastcell = newcell; /** * idno null */ StudentCell find( int idno ) { StudentCell nextcell = firstcell; while( nextcell!= null ) { if( nextcell.student.idno == idno ) return nextcell; if( nextcell.student.idno > idno ) return null; nextcell = nextcell.nextcell; return null; /** * <br> * idno true */ boolean delete( int idno ) { StudentCell findcell = find( idno ); if( findcell == null ) return false; // if( findcell == firstcell ) { // if( findcell == lastcell ) { // firstcell = null; lastcell = null; else { firstcell = firstcell.nextcell; firstcell.precell = null; else if( findcell == lastcell ) { //

251 3.12 Java API 237 lastcell = lastcell.precell; lastcell.nextcell = null; else { // findcell.precell.nextcell = findcell.nextcell; findcell.nextcell.precell = findcell.precell; return true; /** * */ void print() { StudentCell nextcell = firstcell; System.out.println( " " ); while( nextcell!= null ) { nextcell.student.print(); nextcell = nextcell.nextcell; System.out.println(); Java TreeSet TreeMap 3.18 ( ) ( root) ( leaves) (innner node) (Binary tree) (Binary search tree) ( 3.18 ) ( ) BinarySearchTreeExample.java package section0311; /** * <br> *

252 238 3 Java II 1 (-2.1,2.6) (-1.6,-0.5) 2 (-2.5,2.3) (0.5,1.0) 5 (1.6,-3.1) (0.6,-1.1) (2.3,3.2) 7 (3.7,0.8) 8 (5.6,-5.1) (1.0,3.6) 9 (6.6,2.5) 10 (7.3,-3.1) (6.1,0.5) 17 (7.9,0.3) (4.8,-1.7) (3.9,-2.4) 15 (4.3,3.8) (-0.9,5.2) */ public class BinarySearchTreeExample { // y double[][] pointdata = { {-2.1, 2.6, {-2.5, 2.3, {-1.6,-0.5, { 0.5, 1.0, { 1.6,-3.1, { 2.3, 3.2, { 3.7, 0.8, { 5.6,-5.1, { 6.6, 2.5, { 7.3,-3.1, { 1.0, 3.6, { 6.1, 0.5, { 4.8,-1.7, { 0.6,-1.1, { 4.3, 3.8, { 3.9,-2.4, { 7.9, 0.3, {-0.9, 5.2 ; // Node[] nodes = PNode.makeNodeArray( pointdata ); // BinarySearchTree pointtree = new BinarySearchTree( nodes ); // // // pointtree.dpsprint(); // pointtree.bfsprint(); /** * <br> * */

253 3.12 Java API 239 abstract class Node implements Comparable<Node> { /** */ static int sno = 0; /** */ int no; /** */ Node parent; /** */ Node left; /** */ Node right; Node() { this.no = ++sno; this.parent = null; this.left = null; this.right = null; /** * */ class PNode extends Node { /** */ Point point; PNode(Point point ) { super(); this.point = point; /** */ public String tostring() { String sleft = (left==null)?".":string.valueof(left.no); String sright = (right==null)?".":string.valueof(right.no); String sparent = (parent==null)?".":string.valueof(parent.no); return String.format("%2d%s: l=%2s r=%2s p=%2s", this.no, point.tostring(), sleft, sright, sparent); /** * PNode pointdata x y * PNode */ static PNode[] makenodearray( double[][] pointdata ) { PNode[] nodes = new PNode[pointData.length]; for(int i=0; i<pointdata.length; i++) { nodes[i] = new PNode(new Point( pointdata[i][0], pointdata[i][1] )); return nodes; /** * <br> * <br> * */

254 240 3 Java public int compareto(node other) { return this.point.compareto(((pnode)other).point); /** * <br> * */ class BinarySearchTree { /** */ Node root = null; /** * Point points Point */ BinarySearchTree(Node[] nodes) { for(int i=0; i<nodes.length; i++) { add( root, nodes[i] ); /** * currentnode newnode * */ void add( Node currentnode, Node newnode ) { if( currentnode == null ) { // top root = newnode; return; else { int check = currentnode.compareto( newnode ); if( check < 0 ) { if( currentnode.right == null ) { currentnode.right = newnode; newnode.parent = currentnode; else { add( currentnode.right, newnode ); else if( check > 0 ) { if( currentnode.left == null ) { currentnode.left = newnode; newnode.parent = currentnode; else { add( currentnode.left, newnode ); // if( check == 0 ) return; /** */ void dpsprint() { System.out.println( " "); if( root == null ) { System.out.println( " 2 ");

255 System.out.println(); return; dpsprint( root ); System.out.println(); /** * dpsprint() * currentnode Node */ void dpsprint( Node currentnode ) { if( currentnode == null ) return; dpsprint( currentnode.left ); System.out.println( currentnode.tostring() ); dpsprint( currentnode.right ); /** */ void bfsprint() { System.out.println( " "); if( root == null ) { System.out.println( " 2 "); System.out.println(); return; bfsprint( root ); System.out.println(); /** * bfsprint() * currentnode Node */ void bfsprint( Node currentnode ) { if( currentnode == null ) return; System.out.println( currentnode.tostring() ); bfsprint( currentnode.left ); bfsprint( currentnode.right ); 3.13 (nested class) 4

256 242 3 Java II (static) (static member class) static (nonstatic member class) (anonymous class) (local class) 3 (inner class) (enclosing class) (outer class) NestedClassExample.java ( ) package section0312; public class NestClassExample { A a = new A(); a.print(); A.B b = new A.B(3, 4); b.print(); A.B.sprint(); // class A { int ia; static int sa; A() { this.ia = 1; A.sa = 2; void print() { System.out.printf( "A's print() ia=%d, sa=%d, sb=%d%n", ia, sa, B.sb ); // static class B { int ib; static int sb = 0; B(int ib, int sb) { this.ib = ib; B.sb = sb; void print() { System.out.printf( "B's print() sa=%d, ib=%d, sb=%d%n", sa, ib, sb ); static void sprint() { System.out.printf( "B's sprint() sa=%d, sb=%d%n", sa, sb ); B A A A

257 B A main B b = new B( 1 ) static A a.b b = new a.b(); B A b ( static ) (package-pribate publi) ( ) (private protected ) B private (BankAccount) (Permissions) (?) package section0312; public class StaticMemberExample { BankAccount nodaai = new BankAccount( , " " ); nodaai.setpermissions( new BankAccount.Permissions( true, false, false ) ); nodaai.printforclose(); class BankAccount { // int number; // String name; // Permissions permissions; // BankAccount( int number, String name ) { this.number = number; this.name = name; void setpermissions( Permissions permissions ) { this.permissions = permissions; void printforclose() { // System.out.println( name + " " + (permissions.canclose? " ":" ") ); // static static class Permissions { // boolean candeposit; // boolean canwithdraw; // boolean canclose; // Permissions( boolean cand, boolean canw, boolean canc ) { this.candeposit = cand; this.canwithdraw = canw; this.canclose = canc;

258 244 3 Java II static static public, private, protected, package-private, final, abstract static ( ) static (inner class) static static InnerClassExample.java ( ) package section0312b; public class InnerClassExample { A a = new A(); a.print(); A.B ab = a.new B(5, 6); ab.print(); class A { // int ia; static int sa; B b; A() { this.ia = 1; A.sa = 2; this.b = new B(3, 4); void print() { System.out.printf( "A's print() ia=%d, sa=%d%n", ia, sa ); class B { // int ib=3; B( int ib, int sb ) { this.ib = ib; ia = ib; sa = sb; void print() { System.out.printf( "B's print() ia=%d, sa=%d, ib=%d%n", ia, sa, ib ); static A.B ab = new A.B(4); public, private, protected, package-private, final, abstract

259 ( ) Arrays sort AnonymouseClassExample.java ( ) package section0312; import java.util.arrays; import java.util.comparator; public class AnonymouseClassExample { String[] array = {"b", "B", "A", "C", "a", "c"; Arrays.sort( array, new Comparator<String>() { public int compare(string s1, String s2) { return s1.compareto(s2); ); for(string s : array) System.out.println( s ); static 3.14 (parallel computing) 2 (multi-process) (multi-thread) main main main main main main (?)

260 246 3 Java II Java 2 Thread Runnable Java Thread Runnable Thread Thread Thread Thread start run start run run run start ( main ) run run Thread run Thread run ThreadExample01.java (Thread ) package section0314; public class ThreadExample01 { System.out.println( "main thread start..." ); MyThread thread_a = new MyThread(); MyThread thread_b = new MyThread(); thread_a.start(); thread_b.start(); System.out.println( "main thread end..." ); class MyThread extends Thread public void run() { System.out.println( getname() + " thread start..." ); working(); System.out.println( getname() + " thread end..." ); private void working() { int sum = 0; for(int i=1; i<=100000; i++) { sum += i; System.out.println( getname() + ": sum = " + sum );

261 main main thread start... start main thread start... Thread-0 thread start... Thread-1 thread start... main thread end... Thread-0: sum = Thread-0 thread end... Thread-1: sum = Thread-1 thread end... run Thread getname() ( setname(string) ) main 2 run start thread_a.start(); IllegalThreadStateException Exception in thread "main" java.lang.illegalthreadstateexception at java.lang.thread.start(thread.java:705) at threadexamples.threadexample01.main(threadexample01.java:9) start thread B thread A main thread start... main thread end... Thread-1 thread start... Thread-0 thread start... Thread-1: sum = Thread-1 thread end... Thread-0: sum = Thread-0 thread end main ( ) ThreadExample02.java (Thread ) package section0314; public class ThreadExample02 { public static void main(string[] args) throws InterruptedException {

262 248 3 Java II Deposit deposit = new Deposit(); DepositThread thread_a = new DepositThread(" ", deposit, 1000); thread_a.start(); DepositThread thread_b = new DepositThread(" ", deposit, 1000); thread_b.start(); // Thread.sleep(100L); System.out.println( "2 " + deposit.getdeposit() + " " ); class DepositThread extends Thread { Deposit deposit; int money; DepositThread( String name, Deposit deposit, int money ) { super( name ); this.deposit = deposit; this.money = public void run() { System.out.println( getname() + " " + money + " " ); deposit.adddeposit( money ); class Deposit { int deposit; public Deposit() { this.deposit = 0; int getdeposit() { return deposit; void adddeposit( int money ) { this.deposit = this.getdeposit() + money; sleep() : Thread join() : Thread sleep public static void sleep InterruptedException IllegalArgumentException IllegalArgumentException sleep(long) sleep(long, int) ( ) main 100 msec

263 join public final void join InterruptedException join() join(0) join(long) 0 join(long, int) ( ) 2 public static void main(string[] args) throws InterruptedException { Deposit deposit = new Deposit(); DepositThread thread_a = new DepositThread(" ", deposit, 1000); thread_a.start(); DepositThread thread_b = new DepositThread(" ", deposit, 1000); thread_b.start(); // Thread.sleep(100L); thread A.join(); thread B.join(); System.out.println( "2 " + deposit.getdeposit() + " " ); main Runnable Runnable Thread Runnable Runnable run Runnable run Thread start ThreadExample04.java (Runnable ) package section0314; public class ThreadExample04 { System.out.println( "main thread start..." ); Thread thread_a = new Thread( new SubThread("thread_A") ); thread_a.start(); Thread thread_b = new Thread( new SubThread("thread_B") ); thread_b.start(); System.out.println( "main thread end..." ); class SubThread implements Runnable { String name; SubThread( String name ) { this.name = name;

264 250 3 Java II String getname() { return public void run() { System.out.println( getname() + " thread start..." ); working(); System.out.println( getname() + " thread end..." ); private void working() { int sum = 0; for(int i=1; i<=100000; i++) { sum += i; System.out.println( getname() + ": sum = " + sum ); ThreadExample02.java package section0314; public class ThreadExample02 { public static void main(string[] args) throws InterruptedException { for( int i=0; i<100; i++) { Deposit deposit = new Deposit(); DepositThread thread_a = new DepositThread(" ", deposit, 1000); thread_a.start(); DepositThread thread_b = new DepositThread(" ", deposit, 1000); thread_b.start(); // Thread.sleep(100L); thread_a.join(); thread_b.join(); System.out.print( "2 " + deposit.getdeposit() + " " ); if( deposit.getdeposit()!= 2000 ) { System.out.print( " " ); System.out.println(); class DepositThread extends Thread { Deposit deposit; int money; DepositThread( String name, Deposit deposit, int money ) { super( name ); this.deposit = deposit; this.money = public void run() {

265 // System.out.println( getname() + " " + money + " " ); try { Thread.sleep(5L); catch (InterruptedException e) { e.printstacktrace(); deposit.adddeposit( money ); class Deposit { int deposit; public Deposit() { this.deposit = 0; int getdeposit() { return deposit; void adddeposit( int money ) { this.deposit += money; join msec ( 3.19 ) adddeposit() ( ) thread_a adddeposit(1000) deposit 0 円 1000 円 1000 円 2000 円 thread_b adddeposit(1000) 時間の流れ thread_a adddeposit(1000) deposit 0 円 0 円 1000 円 1000 円 thread_b adddeposit(1000) 時間の流れ 3.19 ( 1000 ) adddeposit

266 252 3 Java II synchronized adddeposit synchronized void adddeposit( int money ) { this.deposit += money; BankBooks.java ( ) package section0314; public class BankBooks { BankBook bankbook1 = new BankBook( " 1", ); // BankBook bankbook2 = new BankBook( " 2", ); // // 1000 BankingThread banking1 = new BankingThread( bankbook1, bankbook2, 1000 ); // 5000 BankingThread banking2 = new BankingThread( bankbook2, bankbook1, 5000 ); // banking1.start(); banking2.start(); // bankbook1.print(); bankbook2.print(); System.out.printf( " %n%s : %d %n%s : %d %n", bankbook1.name,14000,bankbook2.name,16000 ); // class BankingThread extends Thread { BankBook book1; // BankBook book2; // int money; // BankingThread( BankBook book1, BankBook book2, int money ) { this.book1 = book1; this.book2 = book2; this.money = money; public void run() { book1.setdeposit(book1.getdeposit() - money); // book2.setdeposit(book2.getdeposit() + money); // // class BankBook { String name; // int deposit; // BankBook( String name, int money ) {

267 3.15 JavaFX ( ) 253 this.name = name; this.deposit = money; // int getdeposit() { return this.deposit; // void setdeposit(int money) { this.deposit = money; // void print() { System.out.printf( "%s : %d %n", this.name, this.deposit ); 3.15 JavaFX ( ) Java 1996 Java 1.0 GUI (Graphical User Interface) AWT (Abstract Window Toolkit) GUI CUI (Character-based User Interface) Java OS write once, run anywhere ( ) AWT 1998 Java 2 GUI Swing Swing AWT OS ( OS GUI ) Java Flash Sun Microsystems Flash JavaFX 2007 JavaFX Script 2011 Oracle JavaFX Script Java Swing JavaFX Java 7 GUI JavaFX (^_^;) Eclipse JavaFX e(fx)clipse: Eclipse JavaFX JavaFX Scene Builder: GUI e(fx)clipse JavaFX Java 7u2 JDK JavaFX Eclipse Scene Builder Eclipse ( ) e(fx)clipse Eclipse

268 254 3 Java II e(fx)clipse - install ( 3.20 ) Eclipse JavaFX javafx e(fx)clipse Scene Builder Scene Builder JavaFX GUI Oracle Scene Builder ( ) Java SE 8u40 Scene Builder GLUON Scene Builder OpenJDK OpenJFX ( ) GLUON GLUON Download Now Scene Builder ( 3.21 ) Gluon Eclipse Scene Builder Eclipse (MacOS Eclipse ) JavaFX SceneBuilder SceneBuilder.exe (MacOS SceneBuilder.app) ( 3.22 )

269 3.15 JavaFX ( ) Scene Builder 3.22 Eclipse Scene Builder JavaFX JavaFX JavaFX section0315 JavaFX Java... JavFX JavaFX Java JavaFX UI FXML JavaFXExample01.java Eclipse JavaFX JavaFX Eclipse JavaFX SDK JavaFX SDK JRE package section0315; import javafx.application.application; import javafx.event.actionevent; import javafx.event.eventhandler; JavaFXExample01.java ( JavaFX)

270 256 3 Java II import javafx.scene.scene; import javafx.scene.control.button; import javafx.scene.layout.stackpane; import javafx.stage.stage; public class JavaFXSample01 extends Application { launch( args public void start(stage primarystage) { Button button = new Button(); button.settext( "Say 'Hello World'" ); button.setonaction(new EventHandler<ActionEvent>() public void handle( ActionEvent event ) { System.out.println( "Hello World!" ); ); StackPane root = new StackPane(); root.getchildren().add( button ); Scene scene = new Scene( root, 300, 250 ); primarystage.settitle( "Hello World!" ); primarystage.setscene( scene ); primarystage.show(); 3.23 JavaFX JavaFXExample01 javafx.application.application JavaFX main Application Application void init() abstract void start(stage) throws Exception Stage void stop() static void launch(string...) JavaFX main main

271 3.15 JavaFX ( ) 257 start JavaFX main main main main launch Application init JavaFX ( ) init start start JavaFX (Stage) (Scene) (SceneGraph) Application start start primarystage JavaFX Stage (components) Scene primarystage.setscene( scene ) Stage Scene (container) Stage show() ( start ) show() void hide() void close() start Exception try catch throws ( throws ) main main Eclipse start start stop stop Stage Label Button ( ) 6 VBox ( ) HBox

272 258 3 Java II AnchorPane FlowPane BorderPane GridPane JavaFX JavaFXExample02.java (JavaFX ) package section0315; import javafx.application.application; import javafx.geometry.pos; import javafx.scene.scene; import javafx.scene.control.label; import javafx.scene.layout.vbox; import javafx.stage.stage; public class JavaFXExample02 extends Application { print( Thread.currentThread(), "main() " ); launch(args); print( Thread.currentThread(), "main() " ); static void print( Thread thread, String message ) { System.out.printf( "%s: %s%n", thread.getname(), message public void init() throws Exception { print( Thread.currentThread(), "init() " public void start(stage primarystage) throws Exception { print( Thread.currentThread(), "start() " ); primarystage.settitle( "JavaFX " ); Label label = new Label(" "); VBox vbox = new VBox(); vbox.setalignment( Pos.CENTER ); vbox.getchildren().add( label ); primarystage.setscene( new Scene( vbox, 480, 240 ) ); primarystage.show(); print( Thread.currentThread(), "start() " public void stop() throws Exception { print( Thread.currentThread(), "stop() " ); main: main() JavaFX-Launcher: init() JavaFX Application Thread: start()

273 3.15 JavaFX ( ) 259 JavaFX Application Thread: start() JavaFX Application Thread: stop() main: main() main launch() JavaFX-Launcher main JavaFX-Launcher init GUI JavaFX Application Thread start GUI start show ( ) stop stop main Stage start Stage Stage Stage JavaFXExample03.java ( ) package section0315; import javafx.application.application; import javafx.stage.stage; public class JavaFXExample03 extends Application { public void start(stage primarystage) throws Exception { primarystage.settitle( " " ); // (= true) primarystage.setresizable( true ); // primarystage.setwidth( 480 ); primarystage.setheight( 240 ); // 640, 360 primarystage.setmaxwidth( 640 ); primarystage.setminwidth( 360 ); // primarystage.show(); ( ) false (Windows MacOS ) ( Stage (public final ) is

274 260 3 Java II JavaFXExample04.java ( ) package section0315; import javafx.application.application; import javafx.scene.scene; import javafx.scene.layout.flowpane; import javafx.scene.paint.color; import javafx.stage.stage; public class JavaFXExample04 extends Application { public void start(stage primarystage) throws Exception { primarystage.settitle( " " ); primarystage.setwidth( 640 ); primarystage.setheight( 480 ); primarystage.show(); Stage newstage = new Stage(); newstage.settitle( " " ); newstage.setwidth( 320 ); newstage.setheight( 240 ); newstage.setalwaysontop(true); newstage.setresizable(false); newstage.show(); Stage newstage2 = new Stage(); newstage2.settitle( " " ); newstage2.setscene( new Scene(new FlowPane(), 480, 360, Color.PINK ) ); newstage2.show(); 3 ( 3.24 ) alwaysontop false true fullscreenexitkey fullscreen false true iconified false true maxwidth, maxheight Double.MAX_VALUE minwidth, minheight 0 width, height 0 resizable true false title opacity scene null x, y Stage

275 (Scene) ( ) setscene Scene Stage Scene Stage setscene Scene Scene GUI GUI ( VBox ) ( ) setscene Java int double 2 Java 5 (enumerated type) ( ) C C ++ enum

276 262 3 Java II (enumerate) enum package section0316; public class PlayCardExample01 { // Card1 card = new Card1( Card1.HEARTS, 8 ); System.out.println( card.tostring() ); // class Card1 { int suit; // int number; // static final int CLUBS = 0; static final int DIAMONDS = 1; static final int HEARTS = 2; static final int SPADES = 3; Card1( int suit, int number ) { this.suit = suit; this.number = number; public String tostring() { String suitname = null; switch( this.suit ) { case CLUBS: suitname = " "; break; case DIAMONDS: suitname = " "; break; case HEARTS: suitname = " "; break; case SPADES: suitname = " "; break; default: throw new IllegalArgumentException(); return suitname + " " + this.number; PlayCardExample01.java ( ) int (Card1 card = new Card1( 5, 8 ); ) 4 0, 1, 2, 3 4 int 4 int bin (static final int CLUBS = 4;)

277 PlayCardExample02.java ( ) package section0316; public class PlayCardExample02 { Card2 card = new Card2( Card2.Suit.HEARTS, 8 ); System.out.println( card.tostring() ); class Card2 { Suit suit; int number; Card2( Suit suit, int number ) { this.suit = suit; this.number = number; public String tostring() { return this.suit.suitname + ":" + this.number; // static class Suit { private final String suitname; static final Suit CLUBS = new Suit(" "); static final Suit DIAMONDS = new Suit(" "); static final Suit HEARTS = new Suit(" "); static final Suit SPADES = new Suit(" "); private Suit( String suitname ) { // this.suitname = suitname; Card2 Suit Card2 Suit Suit private Suit 4 Java 5 enum enum java.lang.enum enum Suit Card3 ( enum?) ( ) PlayCardExample new.java (enum ) package section0316; public class PlayCardExample3 { Card3 card = new Card3( Card3.Suit.HEARTS, 8 ); System.out.println( card.tostring() ); // Card3.Suit.suitPrint(); class Card3 { int number; Suit suit; Card3( Suit suit, int number ) { this.suit = suit;

278 264 3 Java II this.number = number; public String tostring() { return this.suit.tostring() + ":" + this.number; // ( ) enum Suit { // ( ) CLUBS(" "), DIAMONDS(" "), HEARTS(" "), SPADES(" "); // // private final String name; // private Suit( String name ) { this.name = name; // static void suitprint() { for( Suit suit : Suit.values()) { System.out.printf( "[%d] %s(%s)%n", suit.ordinal(), suit.name(), suit.name ); class { enum { ( ) ( ) ordinal() name() ordinary() name() name enum enum package section0316; public enum RGBColor { RED( " ", 0xff0000 ), GREEN( " ", 0x00ff00 ), BLUE( " ", 0x0000ff ); String jname; int value; RGBColor( String jname, int value ) { this.jname = jname; RGBColor.java ( )

279 this.value = public String tostring() { return jname + "(" + String.format("%06x", Value) + ")"; EnumImportExample.java ( ) package section0316; import static section0316.rgbcolor.*; public class EnumImportExample { RGBColor c = GREEN; // RGBColor.GREEN System.out.println( " " + c.tostring() ); 3.17 (annotation) Java 5 ( Eclipse) (Eclipse java.lang.annotation.annotation java.lang ( ) Javadoc DeprecatedExample.java ( : ) package section0317; public class DeprecatedExample { System.out.println( plus(1, 2) ); System.out.println( add(1, 2) ); // plus add plus

280 266 3 Java public static int plus(int a, int b) { return a + b; public static int add(int a, int b) { return a + b; (plus add) Eclipse ( ) public class A { public void print() { /* */ class B extends A public void print( int x ) { /* (Warning) alength Eclipse a alength int[] a = { 1, 2, 3 int alength = a.length; 3.18 System.out.printf int x = 100; int y = 200; System.out.printf( "x = %d%n", x );

281 System.out.printf( "%d + %d = %d%n", x, y, (x+y) ); printf printf Java 5 (variable arity parameter) (arity ) VariableArityExample.java ( ) package section0318; public class VariableArityExample { System.out.println( "sum(1, 2) = " + sum( 1, 2 ) ); System.out.println( "sum(1, 2, 3) = " + sum( 1, 2, 3 ) ); // {11, 12, 13, 14, 15 [2] check( 2, 11, 12, 13, 14, 15 ); static int sum( int... x ) { int sum = 0; for(int i : x) { sum += i; return sum; static void check( int n, int... x ) { System.out.printf( "x[%d] = %d%n", n, x[n] ); int... x int 3 sum( int... x, int... y ) ( x y ) sum( int x, int... y ) sum( int... x, int y ).length ( x.length 0 sum() check( 2 ); ArrayIndexOutOfBoundsException

282 III

283 Apx.2 A A ( A.1 ) A , ( A.2 ) 16 ( A.3 ) A F ( ) 0 F 16

284 A.2 Apx.3 A.2 A.3 16 A x (x hexadecimal:16 ) 0x7a 0x7A bit( ) 8 bits 1 1 byte( ) A

285 Apx.4 A A ) ) ) ) ) ) ) ₂ A A A

286 A.3 Apx.5 n 2 b 1 b 2 b 3 b n x 0 x 2x + b i, (i = 1, 2,..., n) x 10 A A A A3 8 A p p 1 (= p 1 ) p 2 1 (= p 2 ) A

287 Apx.6 A A ( A.8 ) = = = = A ( A.9 ) A A

288 A.4 2 Apx.7 A A A.4 2 n 10 2 A.11 2 p log p A n p log p ( ) [ ] < log 2 10 <

289 Apx.8 A A (= 2 1 ) 1 bit 2 ( A.12 ) 2.5 ( ) A A bits 64 bits Windows OS 64 bits 32 bits 32 bits Emulator ( ) 32 bits 1 bit 0 1 ) 16 bits 16 bits 16 bits 0 bits = = = ( A.13 ) A bits 2 )

290 A.7 2 Apx.9 正の最大整数 A bits A ( ) 16 bits A ( 100) 17 bits 16 bits bits 0 1 A bits bits

291 Apx.10 A A (Fixed Decimal Point Number) (Floating Decimal Point Number) 0.123E-2 E (Exponential) Java = = (Mantissa) (Exponent) bits ( A.15 ) A bits A.9 IEEE 754 IEEE 754 IEEE (Institude of Electrical and Elctrinics Engineers) IEEE bits 64 bits bits ( ) IEEE (^^;) ( ) 127 A.9.1 IEEE IEEE 754 (1 bit) (8 bits) (23 bits) 32 bits ( A.16 ) bit

292 A.9 IEEE 754 Apx ( ) 1 ( ) (127) = 133 = A.16 IEEE 754 A.9.1. IEEE bits ( ) A IEEE bits 1 bit 11 bits 52 bits IEEE bits 0.1 ( A.9.1 ) NaN Not a Number 0 / / / / NaN 0 / A.9.1 IEEE 754

293 Apx.12 A A.10 6 bits 1 bit 2 bits 3 bits 2 ( A.17 ) A IEEE bits A IEEE 754 Java Float.MAX_VALUE, Float.MIN_VALUE

294 Apx.13 B Eclipse B.1 Eclipse Eclipse Eclipse Java Eclipse Java Eclipse Eclipse Neon Apple MacOS Windows All in One 64bits MacOS B.2 Pleiades Eclipse Java Pleiades Windows Pleiades zip MacOS Pleiades dmg JDK JRE Eclipse Eclipse 4.6 Neon Pleiades ( B.2 ) ( B.2 ) OS 32bits 64bits Full Edition Standard Edition 36 Windows OS 32bits 64bits 64 64bits OS bit ( Full Edition, Java ) JRE JDK ( B.2 ) Windows / MacOS

295 付録 B Eclipse のインストール Apx.14 図 B.1 Pleiades のダウンロードの開始ページ 図 B.3 図 B.2 Pleiades の Edition の選択 Pleiades のダウンロード開始 (Windows) ファイル名は Windows 用 pleiades java-win-64bit-jre_ MacOS 用 pleiades java-mac-jre_ dmg でした B.3 Java API ドキュメントのダウンロード Eclipse では プログラムの作成中に Java で用意されているクラスやメソッドのドキュメント (Java API documents) をネットを介して見ることができるのですが そのドキュメントを事前に各自のパソコンにダウンロードして おけば ネットに接続していない環境でも利用出来るようになり便利です そこで ドキュメントをダウンロードする ため Oracle のダウンロードページに移動します URL からわかるように マニュアルの改変で URL が変わる可能性があるので その場合は Google などでキーワー ド Java API ドキュメント と検索して下さい 日本語版ドキュメントのダウンロードはページの下のほうにアーカ イブ ファイルへのリンクがありますので それをクリックします (図 B.4 参照) 最新バージョンの日本語版ドキュメントをダウンロードすることにします この文章を書いている時点でダウンロー

296 B.4 Eclipse Apx.15 B.4 API B.5 8.zip ( B.5 ) Java Eclipse B.4 Eclipse Eclipse B.4.1 ( ) Eclipse Java Eclipse Windows C:Y pleiades Eclipse java MacOS pleiades.app Eclipse java pleiades (MacOS pleiades.app) B.4.2 Windows pleiades-***.zip MacOS pleiades-***.dmg

297 Apx.16 B Eclipse Windows pleiades ( B.6 ) pleiades C:Y ( B.7 ) C:Ypleiades C:YpleiadesYeclipseYclipse.exe ( B.8 ) MacOS Eclipse ( B.9 ) Eclipse Eclipse B.6 Pleiades (1) B.7 Pleiades (2) B.8 Eclipse (Windows) B.9 Pleiades (Mac)

298 B.5 Java API Apx.17 B.5 Java API zip E Windows Eclipse C:Ypleiades ( B.10, B.11 ) C:YpleiadesYE YapiYindex.html ( B.12 ) MacOS Pleiades 1 ( ) 8.zip 8.zip E54527_01 Applications\E \api\index.html zip dmg Eclipse B.10 API (1) B.11 API (2) B.6 Eclipse B.6.1 workspace Windows C:YpleiadesYeclipseYeclipse.exe Eclipse ( B.8 ) Eclipse eclipse.exe (K) ( B.13 ) Eclipse ( B.14 ) MacOS Eclipse LaunchPad Windows

299 Apx.18 B Eclipse B.12 API B.13 Eclipse B.14 Eclipse Windows workspace C:Yjava ( B.15 ) OK Eclipse MacOS workspace Windows

300 B.6 Eclipse Apx.19 B.15 ( B.16 ) (H) (W) B.16 Eclipse (W) (V) ( B.17 B.18 ) B.17 B.18

301 Apx.20 B Eclipse B.6.2 (F) (N) Java Java (P) ( B.19 B.20 ) JRE Java JavaSE-1.8 Java Eclipse Java B.19 Java (1) B.20 Java (2) (N) B.6.3 API Windows MacOS Eclipse Java JRE JRE(J) java 8 (MacOS Java SE 8) (E) ( B.21 ) JRE JRE JRE Ctrl+A (MacOS Command+A) Javadoc ( B.22 ) Javadoc URL

302 B.6 Eclipse Apx.21 B.21 Javadoc (1) B.22 Javadoc (2) B.23 Javadoc (3) B.24 Javadoc (4) Windows C:YpleiadesYE Yapi MacOS E ( B.23 ) ( B.24 )

303 Apx.22 B Eclipse B.6.4 Eclipse Eclipse 6 Java Windows OS MS ( ) ( ) ( ) MS (MacOS Eclipse ) Java Java... OK ( B.25 ) B.25 Font

304 B.6 Eclipse Apx OK Eclipse Eclipse MacOS Eclipse eclipse.ini MacBookAir Eclipse.app Contents/Eclipse/eclipse.ini -Dorg.eclipse.swt.internal.carbon.smallFonts eclipse MacOS Eclipse (Windows -clean ) Applications/Eclipse.app/Contents/MacOS/eclipse -clean Eclipse Windows MacOS Eclipse ( B.26 ) 2 3 ( ) B.26 Eclipse

305 Apx.24 B Eclipse Windows MacOS Eclipse Java B.27 // ${todo ( B.27 ) B.27 Eclipse 2 ( B.28 ) 80 Windows MacOS Eclipse Java / Eclipse

306 B.7 Eclipse Apx.25 B.28 / OK B.7 Eclipse Eclipse -clean Eclipse Windows Eclipse eclipse.exe (C:YpleiadesYeclipse) eclipse.exe -clean.cmd ( B.29 ) MacOS Eclipse -clean /Appications/Eclipse.app/Contents/MacOS/eclipse -clean Eclipse C:Yjava c:ypleiades C:Yjava Eclipse

307 Apx.26 B Eclipse B.29 eclipse.exe -clean.cmd... C:Yjava

308 Apx.27 C javadoc C.1 Javadoc Java API ( C.1 ) Javadoc (Java ) Javadoc Sun Microsystems Java HTML API C.1 API C.2 package sectionc01; // public class Circle { C.1 Circle.java ( )

309 Apx.28 C javadoc // private double radius; // private Point center; // public Circle( Point center, double r ) { this.center = center; this.radius = r; // public Circle( double x, double y, double r ) { this.center = new Point(x, y); this.radius = r; // public double area() { return Math.PI * Math.pow( this.radius, 2 ); // public double circumference() { return 2 * Math.PI * this.radius; // true public boolean includes( Point p ) { if( p.distance( this.center ) <= this.radius ) { return true; else { return false; C.2 Point.java ( ) package sectionc01; // public class Point { // private double x; // private double y; // Point( double x, double y ) { this.x = x; this.y = y; // p public double distance( Point p ) { return Math.sqrt( Math.pow( this.x - p.x, 2 ) + Math.pow( this.y - p.y, 2 ) ); javadoc (/** */ ) Eclipse

310 C.2 Apx.29 / //\s*(.+) /** $1 */ // \s 0 * (.+) /** */ (^^;) Javadoc section01 Javadoc Javadoc sectionc01 2 Circle.java Point.java Javadoc Private ( doc ) URL URL index.html Web Javadoc Javadoc Javadoc HTML HTML ( <br> ) Javadoc C.3 Circle.java ( ) package sectionc01; /** 1.0 */ public class Circle { /** */ private double radius; /** */ private Point center; /** center <br>null r <br> */ public Circle(Point center, double r) { this.center = center; this.radius = r; /** x y r <br> */ public Circle(double x, double y, double r) { this.center = new Point(x, y); this.radius = r; /**

311 Apx.30 C javadoc */ public double area() { return Math.PI * Math.pow( this.radius, 2 ); /** */ public double circumference() { return 2 * Math.PI * this.radius; /** true <br> * p <br>null true false */ public boolean includes( Point p ) { if( p.distance( this.center ) <= this.radius ) { return true; else { return false; C.4 Point.java ( ) package sectionc01; /** 1.0 */ public class Point { /** */ private double x; /** */ private double y; /** x y */ Point( double x, double y ) { this.x = x; this.y = y; /** p other <br>null */ double distance( Point other ) { return Math.sqrt( Math.pow( this.x - other.x, 2 ) + Math.pow( this.y - other.y, 2 ) ); section01

312 C.3 Javadoc C.3 Javadoc Java /** Javadoc @version {@link Sample01#getX() getx Java 8 API

313 Apx.32 D debug D.1 (debugging: ) Eclipse ( D.1 ) D.1 Debug mode D.2 ( D.2 ) D.2.1 Java

314 D.2 Apx.33 D.2 Debug perspective D.2.2 D.2.3 D.2.4 D.2.5