testconst.java.orig

Java安全性编程实例,解压看说明

public class TestConst{
    final  int x[ ]={1,2,3};
       final NewConst y=new NewConst();
    public static void main(String args[] ){
          TestConst t=new TestConst( );
	    t.go( );
                   int[ ] x1=t.x;
                   System.out.println("The code with problem");
                   for(int i=0;i<x1.length;i++){
                             System.out.println(x1[i]);
                   }
                   NewConst x2=t.y; 
                   System.out.println("The code without problem");
                   for(int i=0;i<x2.getConst().length;i++){
                             System.out.println(x2.getConst()[i]);
                   }

                   
    }
    void go(){
              x[0]=20;
             y.getConst()[0]=20;
       }
}


class NewConst{
    private final  int x[ ]={1,2,3};
    public final int[ ] getConst( ){
        int [] s=(int []) x.clone();
             return(s);
   }
}