Call some methods from interface without override all the methods in JAVA

Question

Friends, I have an issue in Java: I'd like to implement one structure but I'm facing some difficulty in doing it, can anyone help me.

interface samp1{
    method1()
    method2()
    method3()
}

interface samp2{
    method4()
    method5()
}
class Samp implements samp1,samp2
{
  // this class needs only method1 from interface samp1 and method 4 from interface samp2
  // I don't want to override all the methods from interface 
}

can anyone propose some solutions for this?

Is there any design pattern available for this? If so, please provide links to reference.

Thanks in advance.

Answer 1

An interface is a contract. It says "My class implements all of these methods".

See: http://docs.oracle.com/javase/tutorial/java/concepts/interface.html

If you don't want that, don't use an Interface.

Answer 2

Java 8 allows default methods in an interface, that are used if the particular method is not overridden when the interface is implemented. For example:

interface MyInterface{
    //if a default method is not provided, you have to override it 
    public int Method1(); 
    public default int Method2(){
        return 2;
    }
}

public class MyClass{
    public static void main(String args[]){
        MyInterface in = new MyInterface(){
            public int Method1(){
                return 0;
            }
        };
        //uses the implemented method
        System.out.println(in.Method1()); //prints 0
        //uses the default method
        System.out.println(in.Method2()); // prints 2
    }
}