Sometimes, a class need execute some specific task when it is triggered by other class calling.
In other words, a morning call service is a callback mechanism in our life.
You tell waiter to call you at six every morning.
Then waiter will give you a morning call when time's up.
And we can use interface to achieve this concept.
public interface MorningCall {
public void call();
}
public class Guest implements MorningCall {
public static void main(String[] args) {
Waiter mWaiter = new Waiter();
mWaiter.makeCall(this);
};
@Override
public void call() {
System.println.out("Guest: I Get Up.");
}
}
public class Waiter {
public void makeCall(MorningCall mMorningCall) {
System.println.out("Waiter: Make a Morning Call At Six O'Clock.");
mMorningCall.call();
}
}
