Interface to implement call back functions

Example to implement callback method using interface.

Define the interface, NewInterface.java.

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package javaapplication1;   public interface NewInterface {     void callback(); }

Create a new class, NewClass.java. It will call the callback method in main class.

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package javaapplication1;   public class NewClass {           private NewInterface mainClass;           public NewClass(NewInterface mClass){         mainClass = mClass;     }           public void calledFromMain(){         //Do somthing...                   //call back main         mainClass.callback();     } }

The main class, JavaApplication1.java, to implement the interface NewInterface - callback() method. It will create and call NewClass object. Then, the NewClass object will callback it's callback() method in turn.

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package javaapplication1;   /**  *  * @web http://java-buddy.blogspot.com/  */ public class JavaApplication1 implements NewInterface{           NewClass newClass;       public static void main(String[] args) {                   System.out.println("test...");                   JavaApplication1 myApplication = new JavaApplication1();         myApplication.doSomething();       }           private void doSomething(){         newClass = new NewClass(this);         newClass.calledFromMain();     }       @Override     public void callback() {         System.out.println("callback");     }   }

Implement callback method, using interface.