【java in think】内部类的闭包与回调

 1 interface Incrementable
 2 {
 3     void increment();
 4 }
 5 
 6 class Callee1 implements Incrementable// 实现类Callee1
 7 {
 8     private int i = 0;
 9 
10     @Override
11     public void increment()
12     {
13         i++;
14         System.out.println("Callee1 increment()被调用" + i + "次");
15     }
16 
17 }
18 
19 class MyIncrement
20 {
21     public void increment()
22     {
23         System.out.println("MyIncrement increment()被调用饿啦");
24     }
25 
26     static void f(MyIncrement mi)
27     {
28         mi.increment();
29     }
30 }
31 
32 class Callee2 extends MyIncrement// 重新定义的子类
33 {
34     private int i = 0;
35 
36     public void increment()
37     {
38         super.increment();
39         i++;
40         System.out.println("Callee2 increment()被调用" + i + "次");
41     }
42 
43     private class Closure implements Incrementable// 内部类实现类Closure
44     {
45 
46         @Override
47         public void increment()
48         {
49             Callee2.this.increment();
50         }
51 
52     }
53 
54     Incrementable getCallbackReference()// 返回接口引用
55     {
56         return new Closure();
57     }
58 }
59 
60 /**
61  * @author linlin 回调类与回调方法
62  */
63 class Caller
64 {
65     private Incrementable callbackReference;
66 
67     public Caller(Incrementable callbackReference)
68     {
69         this.callbackReference = callbackReference;
70     }
71 
72     void go()
73     {
74         this.callbackReference.increment();
75     }
76 }
77 
78 public class CallBacks
79 {
80 
81     public static void main(String[] args)
82     {
83         Callee1 callee1 = new Callee1();
84         Caller caller1 = new Caller(callee1);
85         caller1.go();
86         caller1.go();
87         
88         Callee2 callee2 = new Callee2();
89         MyIncrement.f(callee2);
90         Caller caller2 = new Caller(callee2.getCallbackReference());
91         caller2.go();
92         caller2.go();
93 
94     }
95 
96 }