Introduction to Default Methods (Defender Methods) in Java 8

Default methods are those methods which have some default implementation and helps in evolving the interfaces without breaking the existing code. Lets look at an example:

public interface SimpleInterface {
  public void doSomeWork();
   
  //A default method in the interface created using "default" keyword
  default public void doSomeOtherWork(){
    System.out.println("DoSomeOtherWork implementation in the interface");
  }
}
 
class SimpleInterfaceImpl implements SimpleInterface{
  @Override
  public void doSomeWork() {
    System.out.println("Do Some Work implementation in the class");
  }
  /*
   * Not required to override to provide an implementation 
   * for doSomeOtherWork.
   */
 
  public static void main(String[] args) {
    SimpleInterfaceImpl simpObj = new SimpleInterfaceImpl();
    simpObj.doSomeWork();
    simpObj.doSomeOtherWork();
  }
}

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