Java Callback Implementation Guide

In Java, the callback mechanism is implemented using interfaces. The specific steps are as follows:

1. Create an interface that defines callback methods. For example:

public interface Callback {
    void onCallback();
}

1. In the class that requires a callback, create a method that takes an interface type as a parameter to receive the callback object. For example:

public class Caller {
    public void doSomething(Callback callback) {
        // 在这里执行一些操作
        // 操作完成后调用回调方法
        callback.onCallback();
    }
}

1. Implementing callback methods in the invoking class. For example:

public class MyCallback implements Callback {
    @Override
    public void onCallback() {
        System.out.println("Callback executed");
    }
}

1. Instantiate the callback class and the calling class, then pass the callback object to the calling method. For example:

Caller caller = new Caller();
MyCallback myCallback = new MyCallback();
caller.doSomething(myCallback);

When the doSomething method finishes executing, it will automatically call the onCallback method of the callback object passed in, achieving the callback function. This ultimately implements the callback mechanism in Java.