Java callbacks

interface CallBack {                   //declare an interface with the callback methods, so you can use on more than one class and just refer to the interface
    void methodToCallBack();
}

class CallBackImpl implements CallBack {          //class that implements the method to callback defined in the interface
    public void methodToCallBack() {
        System.out.println("I've been called back");
    }
}

class Caller {

    public void register(CallBack callback) {
        callback.methodToCallBack();
    }

    public static void main(String[] args) {
        Caller caller = new Caller();
        CallBack callBack = new CallBackImpl();       //because of the interface, the type is Callback even thought the new instance is the CallBackImpl class. This alows to pass different types of classes that have the implementation of CallBack interface
        caller.register(callBack);
    }
}

Source: stackoverflow.com

Similar codes

0 vote231 views1 answer
Turn ascii into text javascriot
Java
0 vote270 views1 answer
Validation failed for query for method public abstract java.util.List
Java
1 vote225 views1 answer
Who is James Gosling
Java
0 vote233 views1 answer
Nitrite get repo structure
Java
1 vote208 views1 answer
Javafx detect collision
Java
15 votes212 views2 answers
How to crate an array of integers in java
Java
-1 vote229 views1 answer
Java confirmation dialog
Java
0 vote224 views1 answer
Core Java tutorial
Java
1 vote211 views3 answers
How to sort arraylist in java
Java
0 vote220 views1 answer
Zebra zpl print java
Java