匿名内部类提供闭包的功能

interfaceIncrementable

{

       void increment();

}

classCallee1 implements Incrementable

{

       private int i = 0;

       public void increment()

       {

              i++;

              System.out.println(i);

       }

}

classMyIncrement

{

       public voidincrement(){System.out.println("Other");}

       static void f(MyIncrementmi){mi.increment();}

}

classCallee2 extends MyIncrement

{

       private int i = 0;

       public void increment()

       {

              super.increment();

              i++;

              System.out.println(i);

       }

       private class Closure implementsIncrementable

       {

              public void increment()

              {

                     Callee2.this.increment();//调用当前方法。

              }

       }

       Incrementable getCallbackReference(){returnnew Closure();}

}

classCaller

{

       private Incrementable callbackReference;

       Caller(Incrementable cbh){callbackReference= cbh;}

       void go(){callbackReference.increment();}

}

publicclass Callbacks

{

       public static void main(String[] args)

       {

              Callee1 c1 = new Callee1();

              Callee2 c2 = new Callee2();

              MyIncrement.f(c2);

              Caller caller1 = new Caller(c1);

              Caller caller2 = newCaller(c2.getCallbackReference());

              caller1.go();

              caller1.go();

              caller2.go();

              caller2.go();

       }

}