א א א E2-1F Welcome to Java Programming!

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1 ١٤١ א אא א א ١ אאאא Welcome to Java Programming! אW אF E // Fig. 2-1: Welcome1.java 2. // A first program in Java public class Welcome1 { 5. // main method begins execution of Java application public static void main( String args [ ] ) 8. { 9. System.out.println( "Welcome to Java Programming!" ); } // end method main } // end class Welcome1 אWelcome to Java Programming! אאאאE2-1F אא אE2-1F Welcome to Java Programming! א capital אא J Wאאאא small א -1 אאאא אא אאא אאאא אא א Sumאא sum, K א א אCapital Lettersאאאאא א KSmall Letters -٤٧-

2 ١٤١ א אא א א אאאא -2 א אא Kאאא // Fig. 2-1: Welcome1.java א אא Kא Comment Statement א א ٢ ١ LL אK אאא Kאא אLLאא א א delimiter / *אאאאא Kdelimiter / * /* This is a multiplier line comment it can be split into several lines */ א Compilerאא/*KKKKKKKKKKKK*Lא א אאא א אאא /**אא */א אאאאJavadoc Kאא // A first program in Java אא Kאא אא אאאאאאא א אאאאאאאא אK -٤٨-

3 ١٤١ א אא א א אאא public class Welcome1 { K(identifier)א classא אאא אאאK KEאאF -٤٩- KUser defined classesא Welcome1אאאאclassא אאאא אא classא K(identifier) class אאאא אאאK.Welcome1 $ _(0 9) א KidentifierאאאSampleClassName אאidentifier (a-z, A-Z) אאא J Wאאא Kא J ١ K J ٢ K J ٣ KEE2-2FאאאFאא J ٤ Kאאא J ٥ Kא J ٦ א Welcome1, $Value, _Value.S identified, etc J Wאאא K K K?H? 7button Input filed1 Sum+total public Ea Eb Ec Ed

4 ١٤١ א אא א א אאא Java Keywords abstract boolean break byte case catch char class continue default do double else extends false final finally float for if implements import instanceof int interface long native new null package private protected public return short static super switch synchronized this throw throws transient true try void volatile while אאאE2-2F Kאאאאא אאKpublicEclassFא אא?Kjava?classאאאא אאא?Kjava?אאא KjavaאאאאKאאאא (class) א א { אאאאא א(class)א Kאאא} -٥٠-

5 ١٤١ א אא א א א(class)אאא Kאאאא אאאאאאאKjavaאK אאאא W K١ K٢ אאאW Kאאאאאאא אא // main method begins execution of Java application E١Fא6-11אא אאאא אאאW אא public static void main( String args[ ] ) mainאא(java Application)א א (block) אא mainאmainאאא א (method) א EclassFKEאFmethod mainאא א א mainאkאא אאא אKא (methods) אאאK Fא methodeאfvoid אא EאKKKKKKKKKKKKKKאא J -٥١-

6 ١٤١ א אא א א method mainאאאא Kאאאא אאאא{אmain Kmethod Kmethod main}אאאא אאאclassאאאא Kאאmainאאאא אא System.out.println( "Welcome to Java Programming!" ); א Welcome to Java Programming!אא אK??אאStringאאString Kאא אSystem.outאאObject אK Standard Output Kאאאאאא אאאאSystem.out.printlnא Methodא אאWindow א אאאאאCommand KאאEnter Kא(Java Statement)א;אאא א א K א אTerminal KStatement -٥٢-

7 ١٤١ א אא א א W אEא Fא Kא אאאאא אאא K methodclassא אmethod Kאאאא } // end method main } // end class Welcome1. אא (class)אא -٥٣-

8 ١٤١ א אא א א אא אKאאא Javaאאאאאאאא אא אאאאKKawa, Forte Kאאא אאאאא אאאאאאא J ١ Javac Welcome1.Java אESyntax Errors Fאא אאאאKא אאא אאא אאK אאא No Errorsאא.Byte code אWelcome1.class Kאאbyte codeאא אאאאWelcome1 אאKאאjava K אא.classאא אאאאmain methodא אאByte CodeאאKא Kclassאאאא אאW K??א Forteאא אא אאאKאאאאא אאא אא Kא Println -٥٤-

9 ١٤١ א אא א א אא א אProgramming! Welcome to Java KE٤Fאא אאWelcome to Java Programming! אW٢ 1. // Fig. 2-3: Welcome2.java 2. // Printing a of text line with multiple statements public class Welcome2 { // main method begins execution of Java application 7. public static void main( String args[ ] ) 8. { 9. System.out.print( "Welcome to " ); 10. System.out.println( "Java Programming!" ); 11. } // end method main 12. } // end class Welcome2 אE2-3F אE2-1Fאאאא א אK אאstatements. // Printing a of text line with multiple אא אאא public class Welcome2 { KWelcome2אא אאאאאmain Kmethod System.out.print( "Welcome to " ); System.out.println( "Java Programming!" ); -٥٥-

10 ١٤١ א אא א א Welcome אאאאאאאKאאאto אאאאאאא KאאאאאtoJava Programming! אprint אprintאprintln, אא Kאאאאprintln אאאאאאא אאK אאא אאאאא 1. // Fig. 2-4: Welcome3.java 2. // Printing multiple lines with a single statement. KNewLine Character? \n?אא 4. public class Welcome3 { // main method begins execution of Java application 7. public static void main( String args[ ] ) { 10. System.out.println( "Welcome\nto\nJava\nProgramming!" ); 11. } // end method main 12. } // end class Welcome3 Welcome to Java Programming! אאE2-4F -٥٦- א אא אאאE2-4F אאא \n אאאא Kאאאא 3.

11 ١٤١ א אא א א Programming! ر Welcome t o Java // Printing multiple lines with a single statement. א: ٣ אא Kאאאאאא אאא public class Welcome3 { تعريف א א K Welcome3 אא System.out.println( "Welcome\nto\nJava\nProgramming! ); אאאKאאאא אא \ אKאn, אescapeE\F Kאאאא אאאאאאאאא אאא\n escape sequenceא escape sequence Kאאאאאא Kאescape sequenceאe2-5f אא \n \t \r \\ \? א אאאאK אאאאK אאאאאאKcarriage return א א?\?K אאK escape sequencee2-5f -٥٧-

12 ١٤١ א אא א א אא אא אאאא אאא אאאאא אאMicrosoft internet explorer, Netscape Navigator א אאאאא אK א methods JOptionPane אclassאא Kאאא ٤ אא Welcome to Java Programming!א 1. // Fig. 2-6 : Welcome4.java 2. // Printing multiple lines in a dialog box // Java extension packages 5. import javax.swing.joptionpane; // import class JOptionPane 6. public class Welcome4 { // main method begins execution of Java application 9. public static void main( String args[ ] ) 10. { 11. JOptionPane.showMessageDialog( 12. null, "Welcome\nto\nJava\nProgramming!" ); System.exit( 0 ); // terminate application 15. } // end method main 16. } // end class Welcome4-٥٨-

13 ١٤١ א אא א א אאא E2-6F K.message Dialogאא א E2-6F אאאאאאאא אא Kאא א א א אא(packages) א אא(classes) APIאKjava Application Programming Interface (java API).(Extension packages)אא(core packages)אא אאKjavaxאאjavaאאא אאאKאאאאא אאKJava.sun.com אJOptionPaneאאאE2-6Fאא א javax.swing -٥٩- אאאpackages // Java extension אאאאא J אאאKimport Wimport K(Java)אimport K(Javax)אאimport KDeitelאimport K١ K٢ K٣

14 ١٤١ א אא א א אא import javax.swing.joptionpane; // import class JOptionPane אאimportא import KJOptionPaneאאא א Kא אא א APIאאא API אאאאאimport Kאאאא אAPIאאאאא אאJava. sun. com/ j2se/1.3/docs/api/index.html Java.sun.com/ j2se/1.3/docs.htmlאא W Kאאאאאimportאא א א JOptionPaneאאאאא א אאאאKjavax.swing אGUIgraphical user interfaceאאא Kאאא אאא JOptionPane.showMessageDialog( null, "Welcome\nto\nJava\nProgramming!" ); אאshow.Message.Dialogאmethod אא א K??(two arguments) methodאkjoptionpane אא? null?אא אargument) (first אא אFאאאnull? אאאE? Kאאא secondargumentאא -٦٠-

15 ١٤١ א אא א א JOptionPaneאא methodshowmessageאmethodא אאאאmethodאKStatic Method אאmethodאאא class name. method name (arguments) KE2-7Fאאא11-12א אאאאאאMessageאא אאOKאאKא אKOK رسالة אאE2-7F אKmethodאא אאאאאא אK K(Identifier)אאא System.exit( 0 ); // terminate application אאא אאא exitאmethod אאא GUIאאאאאKאSystem א אאאאאאאKא אKmethodאאאאאא method אאKCapitalאsystemאא -٦١-

16 ١٤١ א אא א א אא Java.langאJava.langאאא אאאmethodsאאKimport א אKאmethodexit(0) (argument) -٦٢- אאK ٥ אאאא א אאאאE2-8F 1. // Fig. 2-8 : Addition.java 2. // An addition program // Java extension packages 5. import javax.swing.joptionpane; // import class JOptionPane public class Addition { // main method begins execution of Java application 10. public static void main( String args[ ] ) 11. { 12. String firstnumber; // first string entered by user 13. String secondnumber; // second string entered by user 14. int number1; // first number to add 15. int number2; // second number to add 16. int sum; // sum of number1 and number // read in first number from user as a string 19. firstnumber = 20. JOptionPane.showInputDialog( "Enter first integer" ); 21.

// add the numbers 30. sum = number1 + number2; 31. 32. // display the results 33. JOptionPane.showMessageDialog( 34.

17 ١٤١ א אא א א 22. // read in second number from user as a string 23. secondnumber = 24. JOptionPane.showInputDialog( "Enter second integer" ); 25. // convert numbers from type String to type int 26. number1 = Integer.parseInt( firstnumber ); 27. number2 = Integer.parseInt( secondnumber ); // add the numbers 30. sum = number1 + number2; // display the results 33. JOptionPane.showMessageDialog( 34. null, "The sum is " + sum, "Results", 35. JOptionPane.PLAIN_MESSAGE ); System.exit( 0 ); // terminate application } // end method main } // end class Addition אאE2-8F -٦٣-

18 ١٤١ א אא א א -٦٤- א אאאא // Fig. 2-8 : Addition.java // An addition program. Kאאאא אאא importאא אא KאאאEF אא import javax.swing.joptionpane; // import class JOptionPane אאJOptionPaneאאאא Kאאjavax.swing אא אא } public class Addition classאאeאfאא KAddition.javaאא Addition }אאא {אא method main אK٤١א ٣٩אאא א١١אא אE٤٠W١٠ F אאאKmain אאאא String firstnumber; // first string entered by user String secondnumber; // second string entered by user Kdeclaration statements אא

19 ١٤١ א אא א א declaration statements אאאאVariables אאא א אאא אא אאאאmethod א א אא אא א א J אאidentifiers Wאא _ $ (0 9)אA-Z a-zאאj א J J אא J _ $ J א א א א א א א אKאאאsecondNumberfirstNumberאא אאאEJava.langאאFString אF?;?KString אEאא אא אאאאK א א א אא Kאאאאאאאאא אאאא String firstnumber, // first string entered by user secondnumber; // second string entered by user 14 int number1; // first number to add 15 int number2; // second number to add 16 int sum; // and sum of number1 numbe א ١٤ ١٦J -٦٥-

20 ١٤١ א אא א א intאnumber1, number2 and sumאאא KEאKKKKKKKKKKK200, 11, 7Fאאא אאאאPrimitive data type אאאE2-9F א אא KEbitsF א א א א אErangeF א אEtypeF boolean char byte short int long float double ESize in bitsf ١ True or false to FFFF٠٠٠٠ EvalueFא -128 to ,768 to ,147,483,648 to +2,147,483,647-9,223,372,036,854,775,808 to +9,223,372,036,854,775, E+38 to E E+308 to E+308 אאאאE2-9F אK אא אא אא אא 18// read in first number from user as a string Kאאאאאאאא -٦٦-

21 ١٤١ א אא א א אאא 19 firstnumber = 20 JOptionPane.showInputDialog( "Enter first integer" ); methodאאאאstringאא KE2-10Fאא JOptionPane.showInputDialog אE2-10F showinputdialogאא(argument) א Kאprompt א אEnterOKאאא אK firstnumber אא אאא 22 // read in second number from user as a string אאאאאאא 23 secondnumber = 24 JOptionPane.showInputDialog( "Enter second integer" ); ٢٤J אא ٢٣ א א א א א אא secondnumber א٢٥ // convert numbers from type String to type int -٦٧-

22 ١٤١ א אא א א א אאאאא אאאK אא ٢٦ ٢٧J 26 number1 = Integer.parseInt( firstnumber ); 27 number2 = Integer.parseInt( secondnumber ) אאאאאאאא KאאאfirstNumber, secondnumber אEIntegerאmethod FInteger.parseIntאmethodא java.lang אInteger א אK אאאKimportאאאא number1, Kאאnumber2 WאאDouble א variable1= Double.parseDouble (variable2) Kאאdouble, String אאvariable1, variable2 א٢٩ // add the numbers אאאא א ٣٠ sum = number1 + number2; ٢٩?H?אאnumber1, number2 אאא אאאK?Z?אאsum אא אאKאאאאא א אnumber2 אאאnumber1 אאא WאEHFאאאKsum א אnumber1, number2 אא אאאאאאא Kאא -٦٨-

23 ١٤١ א אא א א ٣٦J א ٣٤ ٣٤ JOptionPane.showMessageDialog( ٣٥ null, "The sum is " + sum, "Results", ٣٦ JOptionPane.PLAIN_MESSAGE ); אאאאא JOptionPane.showMessageDialog method א J W (Four arguments) Kאאאא אאnull J ١ אאאאאאאא J ٢ sumאאא?+?אאא "The sum is " + sum K"The sum is "א אא?+?אאאא KEאאFא אאאאאאאא אא J ٣ راجع شكل (2-8) السابقK ) "Results" אאא JOptionPane.PLAIN_MESSAGEאאאאK J ٤ אאאאאא E2-11Fאאאאא א א אא א א אא א? אאאאE2-11F -٦٩- JOptionPane. ERROR_ MESSAGE JOptionPane. INFORMATION_ MESSAGE JOptionPane. WARNING_ MESSAGE JOptionPane. QUESTION_ MESSAGE JOptionPane. PLAIN_ MESSAGE

24 ١٤١ א אא א א אא אאאאא Wאא אאAssignments =א א xא1 xא1.5א aא A א Wאא W x = 1 ; radius = 1.0 ; a = A ; x=1.0א אW intx א Kאdouble K1 = xאאאא Wא area = radius * radius * ; x = x + 3 ; x + = 3אאא אאאאאאאא Kא Wאאאאאאאאא -٧٠-

25 ١٤١ א אא א א א c = c + 7 c + = 7 d = d - 4 d - = 4 e = e * 5 e * = 5 f = f / 3 f = f / 3 g = g % 9 g % = 9 אאאאE12F -٧١- א + = - = * = / = % = אא א- -א+ +אא אאאc אאאאא א c + = 1; c = c + 1; אאאא אא אK אאאאאאאא א 1אaא aאא אאא aאא אאא 1אaא 1אbא bאא אאא aאא אאא אbא ١ + + a + + a --b b-- אאE13F HH

26 ١٤١ א אא א א 1. // Fig Increment.java 2. // Preincrementing and postincrementing public class Increment { 5. public static void main( String args[] ) 6. { 7. int c; c = 5; 10. System.out.println( c ); // print System.out.println( c++ ); // print 5 then postincrement 12. System.out.println( c ); // print System.out.println(); // skip a line c = 5; 17. System.out.println( c ); // print System.out.println( ++c ); // preincrement then print System.out.println( c ); // print } 21. } אאאאאאK אאאאE2.14F -٧٢-

27 ١٤١ א אא א א א א10 5cא System.out.println( c ); // print 5 א 11 system. out. println( c + + ); 55cאאאאאא System.out.println( c ); // print 6 System.out.println ( ); c = 5 ; c = 6١אcאאא 6c א12 א 14 א16 c5א א17 5cא System.out.println( c ); // print 5 א18 System.out.println( ++c ); // preincrement then print 6 6 cאאאא System.out.println( c ); // print 6 אאאאאא 6 א 6c19-٧٣-

28 ١٤١ א אא א א אא אאאאאא א אא א א f+7 f+7 H f-7 f-7 J b*m bm G x/y x L r%s r mod s אאE2.15F אאאאאאאאא KE Fא ELFא EGF אאאאאא 1 7 / 4 Kאאא317 / 5 אאאאE Fא 37 % 4א 217 % 5א KאאאE Fאאא syntax errore Fאאא -٧٤-

29 ١٤١ א אא א א -٧٥- אא אאאאא a * (b+c)אa Wאאאא אאא אאאJ ١ Kאאא אאאאאאJ ٢ KKKKאא אEא א אFאאJ ٣ אאאאאאKא Kאאא אאאאאJ ٤ Kאאאא אאאאאא y=mx+b z= pr % q + w/x y=x +bx +c y=m*x +b; אJ Kאm*xאא z = p * r % q + w / x - y ; אJ אאא אאאאאאא y = a * x * x + b * x + c אJ

30 ١٤١ א אא א א Wאאאא a = 2, b = 3, c = 7, x = 5 y = 2 * 5 * * 5 + 7; אא 2 * 5 = 10 y = 10 * * 5 + 7; אא 10 * 5 = 50 y = * 5 + 7; אא 3 * 5 = 15 y = ; אאא = 65 y = ; אא = 72 אא y = 72; אאאאאאאא Y = (a * x * x) + ( b * x ) + c ; -٧٦-

31 ١٤١ א אא א א אא javaאאאאאא א א א And && א Or אNot > אאE2.16F א falsetrueאאאאאא.false true.trueאאtrue אאא&&אא.falseא&&א א אא java אאאאא א.אא אא א אא. א trueאא&&אא falseאא trueאאאא.trueא.אאאאjava א אא.אאא>אאא אאא אאaא!a true א java.falseאאאאאאא.א.a=!a -٧٧-

١٤١ א אא א א אא אאאאאאאאאאא W 1. // Fig. 2.17 : Logical.java 2. // Logical Operator 3. public class Logical 4. { 5. public static void main ( String [] args ) 6. { 7.

32 ١٤١ א אא א א אא אאאאאאאאאאא W 1. // Fig : Logical.java 2. // Logical Operator 3. public class Logical 4. { 5. public static void main ( String [] args ) 6. { 7. //declare & initialize test variable 8. boolean a = true, b = false ; 9. boolean c1 =(a && a); // test if both are true 10. boolean c2 =(a && b); 11. boolean c3 =(b && b); boolean c4 =(a a) ; //test if either is true 14. boolean c5 =(a b); 15. boolean c6 =(b b); boolean c7 =!a; // invert initial values 18. boolean c8 =!b; // display the results 21. System.out.println ( and:\n1: +c1+ 2: +c2+ 3: +c3); 22. System.out.println ( or:\n4: +c4+ 5: +c5+ 6: +c6); 23. System.out.println ( not:\n7: +c7+ 8: +c8); 24. } 25. } אאE2.17F -٧٨-

33 ١٤١ א אא א א א א8א אאb a boolean true Kאfalse א9,10,11 &&אאc1,c2,c3אא א13,14,15 אאc4,c5,c6אא א 17,18 >אא c7,c8א א 21,22,23.c1,c2,c3,c4,c5,c6,c7,c8אא -٧٩-

34 א ١٤١ אא א א -٨٠- אאאWאאא אאifאא K Kifאאאifאאאא Kאאאif אW אאאאאאifא Wאאאא א א א א אא א = == x==y yx!= x!=y yx אE2.18F אא א אא א אא א > > x>y yx < < x<y yx >= x>=y yx <= x<=y yx אאE2.19F W <= == >= < = ==!=א >=!= Ksyntax errorא => =<אאא =! syntax error אאif6אא Kאאא

35 ١٤١ א אא א א א אאאא אאא א if אאKnumber1 number2 1. // Fig. 2.20: Comparison.java 2. // Compare integers using if structures, relational operators 3. // and equality operators // Java extension packages 6. import javax.swing.joptionpane; public class Comparison { // main method begins execution of Java application 11. public static void main( String args[] ) 12. { 13. String firstnumber; 14. String secondnumber; 15. String result; 16. int number1; 17. int number2; // read first number from user as a String 20. firstnumber = 21. JOptionPane.showInputDialog( "Enter first integer:" ); // read second number from user as a String 24. secondnumber = 25. JOptionPane.showInputDialog( "Enter second integer:" ); // convert numbers from type String to type int 28. number1 = Integer.parseInt( firstnumber ); 29. number2 = Integer.parseInt( secondnumber ); // initialize result to empty String result = ""; 34. if ( number1 == number2 ) 35. result = number1 + " == " + number2; if ( number1!= number2 ) 38. result = number1 + "!= " + number2; 39. -٨١- אK אאאאK

36 ١٤١ א אא א א 40. if ( number1 < number2 ) 41. result = result + "\n" + number1 + " < " + number2; if ( number1 > number2 ) 44. result = result + "\n" + number1 + " > " + number2; if ( number1 <= number2 ) 47. result = result + "\n" + number1 + " <= " + number2; if ( number1 >= number2 ) 50. result = result + "\n" + number1 + " >= " + number2; // Display results JOptionPane.showMessageDialog( 55. null, result, "Comparison Results", 56. JOptionPane.INFORMATION_MESSAGE ); 57. System.exit( 0 ); // terminate application } // end method main } // end class Comparison -٨٢-

37 ١٤١ א אא א א אE2.20F -٨٣-

38 ١٤١ א אא א א א 8א Comparisonאא public class Comparison { 59א11אא mainא String firstnumber; String secondnumber; String result; int number1; int number2; Kא א1713 mainאאא Stringאא٣ אאאאאאfirstNumber אאאאאאsecondNumber אresult intא٢ אאאnumber1 אאאnumber2 אאאאאאא String firstnumber, secondnumber, result; firstnumber = JOptionPane.showInputDialog( "Enter first integer:" ); W א ٨٤-

39 ١٤١ א אא א א firstnumber אאאאאאא string א secondnumber = JOptionPane.showInputDialog( "Enter second integer:" ); אאאאאא StringsecondNumber א number1 = Integer.parseInt( firstnumber ); number2 = Integer.parseInt( secondnumber ); אint String אא אאfirstNumber א28 number1 אאsecondNumber א29א number2. א 33 result = ""; resultא empty stringאא א methodאאא אאאאKאאאאא : אאאאmethodאאא: -٨٥- syntax error אא 34-35א if ( number1 == number2 ) result = number1 + " == " + number2; אאififif ٣٤א٣٥אifאאאא (;)אא אאא.אא 34אאא

40 ١٤١ א אא א א אאnumber2 number1 result = result + number1 + == + number2; אא result + number1 + == + number Kresult number2 number1 stringאstring string concatenationאא אאאnumber2 number1 result. : syntax errorif(==)(=)א if(number1 == number2);א.אאא -٨٦-

41 ١٤١ א אא א א אאא E١ אאאא J א EF KאLL J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J EF אא אJ J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J EF*, /, %, +, - אאאאJ J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J EF stringintinteger.parseint אJ J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J -٨٧-

42 ١٤١ א אא א א Wאאאא integerstring אאage א K value J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J אא10numberאא J אW The variable number is not equal to 10 J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J WאאאE٣ - א if ( c < 7 ); JoptionPane.showMessageDialog (null, c is less than 7 ); J E٢ J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J if ( c => 7 ) JoptionPane.showMessageDialog (null, c is equal or greater than 7 ); J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J J -٨٨-

43 ١٤١ א אא א א אאאא J אKא?is larger?אאא K? אא? these number are equal אאאאJ א אא א אאאאאK אאאאאJ ٦-٨٩- Kאא אא π = אאא אאMath. PIאאאW א א5אאאJ ٧ אאאאK KאאאאאW אאאאJ ٨ Kאאא 2א אאW K2א02 אאאאJ ٩ Kאאא אאאא 5 J ١٠ Kאא א42339אאW ٤ ٥

Copyright 1999 by Deitel & Associates, Inc. All Rights Reserved.

Copyright 1999 by Deitel & Associates, Inc. All Rights Reserved. CHAPTER 2 1 2 1 // Fig. 2.1: Welcome1.java 2 // A first program in Java 3 4 public class Welcome1 { 5 public static void main( String args[] ) 6 { 7 System.out.println( "Welcome to Java Programming!" );