For the post on interface, please click [here](). There are many ways to work with interface in java basically to remove the unnecessary code. Here's a program to showing two of these.

```
package Polymorphism;

interface A{
	void output();
}

public class InterfaceClassLambda {

	public static void main(String[] args) {
		A obj=new A(){
			public void output() {
				System.out.println("Hello World");
			}
		};
		obj.output();
	}

}

```

<br>

Or you can work with interface through a mechanism known as Lambda Expression, where you can create function without requiring a class.

```
interface A{
	void output();
}

public class InterfaceClassLambda {

	public static void main(String[] args) {
		A obj= () ->
				System.out.println("Hello World");
			
		obj.output();
	}

}
```

Both will show the same output when executed.