public interface ICallback {
  public void func();
}
   
public class ClassWithCallbackFunction implements ICallback{
  public ClassWithCallbackFunction() {
  }
  public void func(){
  System.out.println("cccccccccccccccccc");
  }
}
   
public class Caller {
  ICallback callback;
  public void doCallback() {
  callback.func();
  }

  public void setCallback(ICallback callback) {
  this.callback = callback;
  }

}
   
public class MainClass {
  public MainClass() {
  }

  public static void main(String[] args) {
  Caller caller = new Caller();
  caller.setCallback(new ClassWithCallbackFunction() {
  public void func() {
  System.out.println("aaaaaaaaaa");
  }
  });
  caller.doCallback(); //?????????????  why not print
  }
} 

//我的机器能打印aaaaaaaaaa，你的机器神马牌子的，高级不愿意打印它们


interface ICallback {
    public void func();
}

class ClassWithCallbackFunction implements ICallback {
    public ClassWithCallbackFunction() {
    }

    public void func() {
    System.out.println("cccccccccccccccccc");//实现接口方法
    }
}

class Caller {
    ICallback callback;

    public void doCallback() {
    callback.func();
    }

    public void setCallback(ICallback callback) {
    this.callback = callback;
    }

}

public class MainClass {
    public MainClass() {
    }

    public static void main(String[] args) {
    Caller caller = new Caller();
    caller.setCallback(new ClassWithCallbackFunction() {
        public void func() {//这里已经重写了func方法，你不重写这个它，它就会打印"cccccccccccccccccc"
        System.out.println("aaaaaaaaaa");
        }
    });
    caller.doCallback(); // ????????????? why not print
    }
}
/*output:
aaaaaaaaaa
*/

------解决方案--------------------
eclipse  中 调用 debug 来调试
既可知道整个代码的执行步骤 即程序的调用过程
也能知道程序运行结果的由来

------解决方案--------------------
这里的回调也就是函数的手动调用吧.

------解决方案--------------------
lz,你再试试，确实打印了，是aaaaaaaa!