try2.txt

JAVA编程思想

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    returnType methodName( /* Argument list */ ) { 
      /* Method body */ 
    } 

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      objectName.methodName(arg1, arg2, arg3); 




          a            f ( )                int          f ( ) 


      int x = a.f(); 




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    String                                 String 


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      int storage(String s) { 
          return s.length() * 2; 
      } 




    U ni co d e         String          c h ar 
                                          String16          ( 


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         )                  String                  s         s 

         l e ngth ( )                  String(                        ) 



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     float naturalLogBase() { return 2.718f; } 
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     void nothing2() {} 




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          import java.util.ArrayList; 




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           import java.util.*; 




s t a t i c 


                   new 




                                                        static 
                                                           static 

                    - 
 static                         static              static 

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           class StaticTest { 
             static int i = 47; 
           } 




Static T e st. i        Static T e st        i 

           StaticTest st1 = new StaticTest(); 
           StaticTest st2 = new StaticTest(); 




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      st1 . i    st2 . i          47 


           st2 .(i      static                                            static 

           static         )                       static 


         StaticTest.i++; 




+48+                                      st1 . i    st2 . i 



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         class StaticFun { 
           static void incr() { StaticTest.i++; } 
         } 




      i          Static F u n     inc r( )           + +inc r( )          s tati c 


         StaticFun sf = new StaticFun(); 
         sf.incr(); 




                                   inc r( ) 

         StaticFun.incr(); 




     static 
      static                                                              ( 

               )                                  s tati c              static 

                               m ain( ) 


           static     static 




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            D ate                                                                            Java 


           // HelloDate.java 
           import java.util.*; 

           public class HelloDate { 
              public static void main(String[] args) { 
                  System.out.println("Hello, it's: "); 
                  System.out.println(new Date()); 
              } 
           } 




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           public static void main(String[] args) { 

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p u b l ic argsain( 
             ) m            )  Java         String                 (    5 




          System.out.println(new Date()); 




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                                     D )     p rintl n( )                    D ate 

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          javac HelloDate.java 




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          java HelloDate 




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