Java Programming Language Mr.Rungrote Phonkam

Transcription

1 3 Java Programming Language Mr.Rungrote Phonkam

2 Contents 1. Identify 2. Method Member 3. Literals 4. Data Type 6. Variable

3 1. Identify ก ก Class, Data, Method, Variable, Label, ก ก ก ก ก ก _ $ age, name2, int2float, _name, Currency$ ก ก ก ก 101database, 2name ก ก ก ก Count, count CoUnT ก ก

4 ก ก ( ) ก 1. Identify abstract double int strictfp boolean else interface super break extends long switch byte final native synchronized case finally new this catch float package throw char for private throws class goto protected transient const if public try continue implements return void default import short volatile do instanceof static while

5 1. Identify ก ก ก ก ก ก ก ก MyClass, HelloJava, CollectedData ก ก ก ก color, name, height

6 1. Identify ก ก ( ) ก ก final ก ก ก ก ก SIZE, AMOUNT ก ก ก ก ก ก ก ก ก ก ก countmoney, openfile, setsize, print

7 1. Identify class SimpleClass { SimpleClass java SimpleClass Exception in thread "main" java.lang.nosuchmethoderror: main

8 2. Data Member Access_Level final static Data_Type Data_Name Access_Level ก package final ก ก static ก ก ก static Data_Type Data_Name ( ก ก )

9 2. Data Member ก (Access Level) Keyword public protected package* private Class Instance Extended_Class Extended_Instance Extended_Class Outer Package Extended_Instance Outer Package

10 2. Data Member class SimpleClass { int mydata; mydata SimpleClass java SimpleClass Exception in thread "main" java.lang.nosuchmethoderror: main

11 3. Method Member Access_Level final static Return_Type Method_Name ( Argument_List ) { Statements Access_Level ก final ก ก static ก ก ก static Return_Type ก Method_Name ( ก ก ) Argument_List ก Statements ( )

12 3. Method Member class SimpleClass { void mymethod( ) { mymethod SimpleClass java SimpleClass Exception in thread "main" java.lang.nosuchmethoderror: main

13 4. Literals ก 1, ก x 0X 0 9 ก a z ก A Z ก 0x1D 0X1d ก 29 1D16

14 4. Literals 12.4, 8.0, E5 ก float ก F 3.0F ก ก 32 ก double ก D 3.0D ก ก F 3.0D ก ก ก ก ก 3.0F D 64 ก F D double

15 4. Literals ก ก ก ก (Single Quote) '4' ก 'A' ก '9' ก ก '+' ก ก ก

16 4. Literals ก ก ก (Double Quote) "Java", Hello! World", A", 9", ก "" ก ก NULL " " ก (Space Character) "A" ก A ก 'A'

17 4. Literals ก ก ก true false

18 4. Literals ก ก int i = 10 ; floatf=51.4 ; char ch = 'j' ; ก b == true ; status < 75 ; k=k+4 ;

19 5 Data Type (Primitive Data Type) C Language int, char, float, double,... (Reference Data Type) Instance / Object Array

20 5.1. Primitive Data Type ก byte, short, int long ก ก float double ก ก ก char ก ก boolean ก ก ก ก void

21 5.1. Primitive Data Type Keyword ( ) byte 8 0 short 16 0 int 32 0 long 64 0 float double char ก 16 boolean ก true/false false void - -

22 5.2. Reference Data Type ก ก ( ก ก ก ก ) Integer, StreamInput, Applet, Printer ก ก ก ก ก (Array) ( ก ก ก )

23 6Variables Class Variable Data Member (ก ก ) ก ก ก Data Data Member ก Method Variable กก ก ก Variable Parameter Variable ก ก ก ก ก Parameter

24 6.1. Class Variables Data Member ก ก Primitive Reference class Class_Name { Data_Member Data_Member... Data_Member ก Access_Level final static Primitive_Data_Type Data_Name

25 6.1. Class Variables class PublicStaticData { public static int a = 10; public static void main(string args[]) { System.out.println(a); a main PublicStaticData java PublicStaticData 10

26 ก ก ก 6.1. Class Variables System.out.print (Output) System.out.println (Output) ก System.err.print (Error) ก System.err.println (Error) ก

27 6.1. Class Variables System.out.print System.out.print( ) ( ก out ก ) System ( ก S) System ( ก ก ก )

28 ก 6.1. Class Variables System.out.println( Hello Java ) ก Hello Java System.out.println( Hello + Java ) ก Hello Java ก + ก Hello ก Java System.out.println(a) ก ก a a ก ก

29 ก 6.1. Class Variables \?? ก ก ก \n Linefeed \t Tab \r Carriage Retuen \f Formfeed \b Backspace \\ Backslash \' Single Quote \" Double Quote

30 Octal Escape Code 6.1. Class Variables \nnn nnn \0 \277 \377 Unicode Escape Code \uxxxx xxxx ก \u0041 ก A

31 6.1. Class Variables class TestFinalData { static final char c = J ; public static void main(string args[]) { System.out.println(a); c= a ;

32 6.1. Class Variables class PublicStaticData { public static int a = 10; class UseClass { public static void main(string args[]) { System.out.println(PublicStaticData.a); a PublicStaticData main UseClass Java UseClass 10

33 6.1. Class Variables class PublicStaticData { public int a = 10; class UseClass { public static void main(string args[]) { System.out.println(PublicStaticData.a); a PublicStaticData main UseClass

34 6.1. Class Variables Data Member ก ( ก ) Access_Level final static Class_Name Data_Name Data_Name = new Constructor_Name public final static Double mydouble; mydouble = new MyDouble(10.0); public final static Double mydouble = new MyDouble(10.0);

35 6.1. Class Variables class DefaultStaticRefData { static Double d = new Double(255.53); public static void main(string args[]) { System.out.println(d.toString()); d main DefaultStaticData Java DefaultStaticRefData

36 6.1. Class Variables class PublicStaticRefData { public static String s = Hello ; public static void main(string args[]) { System.out.println(s); s main PublicStaticData Java PublicStaticRefData Hello

37 6.2. Method Variables Primitive Reference class Class_Name { Method_Name() { Method Variable Method Variable... ก final Primitive_Data_Type Data_Name

38 6.2. Method Variables class PrimitiveVariable { public static void main(string args[]) { double d; d = 11.11; System.out.println(d); int a = 3500; System.out.println(a); a d main PublicStaticData java PrimitiveVariable

39 Reference 6.2. Method Variables final Class_Name Data_Name = new Constructor()

40 6.2. Method Variables class RefClass { public int a = 10; class UseClass { public static void main(string args[]) { RefClass objdata = new RefClass (); System.out.println(objdata.a); java UseClass 10

41 6.2. Method Variables a RefClass a objdata.a objdata main UseClass

42 6.2. Method Variables class RefData { public static int a; class UseClass { public static void main(string args[]) { RefData obja = new RefData( ); RefData objb = new RefData( ); obja.a = 10; objb.a = 20; System.out.println(objA.a); System.out.println(objB.a); java UseClass 20 20

43 6.2. Method Variables a RefData a obja a main objb UseClass

44 6.3. Parameter Variables ก ก Primitive Reference Primitive ก ก ( Copy Value) Class Array ก (Reference Value)

45 6.3. Parameter Variables ก กก

46 6.3. Parameter Variables 5 ก 5 Copy Value

47 6.3. Parameter Variables class CopyParam { public static int computeadd(int a, int b) { return a + b; public static int computeminus(int a, int b) { return a - b; public static void main(string args[]) { int number1 = Integer.parseInt(args[0]); int number2 = Integer.parseInt(args[1]); System.out.println( Result of Your Number ); System.out.print( \t + number number2 + = ); System.out.println(computeAdd(number1, number2)); System.out.print( \t + number number2 + = ); System.out.println(computeMinus(number1, number2));

48 6.3. Parameter Variables java CopyParam Result of Your Number = = 33

49 6.3. Parameter Variables 5 ก Reference Value

50 6.3. Parameter Variables class RefParam { public static int computemod(integer a, Integer b) { return a.intvalue( ) % b.intvalue( ); public static void main(string args[]) { Integer number1 = new Integer(args[0]); Integer number2 = new Integer(args[1]); System.out.print(number1 + Mod + number2 + = ); System.out.println( computemod(number1, number2));

51 6.3. Parameter Variables java RefParam 7 2 7Mod2=1 java RefParam Mod 7 = 4

52 6.3. Parameter Variables class MyInt { int i; class ChangeDataInRefParam { public static void Abs1(MyInt a) { a.i = (a.i<0)? a.i * -1: a.i; public static int Abs2(MyInt a) { return ( (a.i<0)? a.i * -1: a.i ); public static void main(string args[]) { MyInt number1 = new MyInt(); number1.i = -55; MyInt number2 = new MyInt(); number2.i = -184; Abs1(number1); System.out.println("Abs1 " + number1.i); System.out.println("Abs2 " + Abs2(number2));

53 6.3. Parameter Variables java ChangeDataInRefParam Abs1 55 Abs2 184