接口传值的收藏！

来源：互联网发布：联想手机淘宝旗舰店编辑：程序博客网时间：2024/05/16 12:26

原文出处：http://www.bdqn.cn/news/201312/12350.shtml

原文出处：http://my.oschina.net/onlytwo/blog/39193

interface Runner //定义接口

{

         int i=3;

       public void start();

        void run();

        void stop();

}

interface Eater extends Runner //接口间可以继承

{

        public final static int j=4;

        void openMouth();

        void upAndDown();

        void goIn();

}

class TT implements Eater //引用接口

{

        public void start()

{

                System.out.println("---------start()-------");

}

        public void run()

{

                System.out.println("---------run()-------");

}

        public void stop()

{

                System.out.println("---------stop()-------");

}

        public void openMouth()

{

                System.out.println("---------openMouth()-------");

}

        public void upAndDown()

{

                System.out.println("---------upAndDown()-------");

}

        public void goIn()

{

                System.out.println("---------goIn()-------");

}

}

public class TestInterface

{

       public static void main(String[] args)

{

                Runner tt=new TT();//接口的引用指向实现的对象

                System.out.println(tt.i);

                System.out.println(Runner.i);

                tt.start();

                Eater ee=new TT();

                System.out.println(ee.j);

                System.out.println(Eater.j);

                ee.start();

}

}

1、接口方法用于回调 (这里定义接口是为了使用其接口方法)：

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publicinterface ICallback {  
  publicvoid   func();  
} 
   
publicclass Caller {  
  ICallback callback;  
  publicvoid doCallback() {  
    callback.func(); 
  } 
   
  publicvoid setCallback(ICallback callback) {  
    this.callback = callback;  
  } 
   
} 
   
publicclass MainClass {  
  publicMainClass() {  
  } 
   
  publicstatic void main(String[] args) {  
    Caller caller = newCaller();  
    caller.setCallback(newICallback () {  
      publicvoid func() {  
        System.out.println("dosth"); 
      } 
    }); 
    caller.doCallback(); 
  } 
}

2、向上转型

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interfacePeople{  
   voidpeopleList();  
} 
classStudent implementsPeople{  
   publicvoid peopleList(){  
       System.out.println("I’m a student.")； 
  } 
} 
classTeacher implementsPeople{  
   publicvoid peopleList(){  
       System.out.println("I’m a teacher."); 
   } 
} 
publicclass Example{  
   publicstatic void main(String args[]){  
       People a;             //声明接口变量 
       a=newStudent();      //实例化，接口变量中存放对象的引用 
       a.peopleList();       //接口回调 
       a=newTeacher();     //实例化，接口变量中存放对象的引用 
       a.peopleList();      //接口回调 
  } 
} 
运行结果： 
I’m a student.  
I’m a teacher.

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