Interface

gistfile1.java

class Htc {
    public String name;
	public Action action ;
	public Htc(Action action) {
		this.action = action;
	}
}

interface Action {
	void doWalk();
}

public class Test {
	
	public static void main(String[] args) {
		Htc htc1 = new Htc(new Action(){
			public void doWalk() {
				System.out.println("Dog is walking");
			}
		});
		
		Htc htc2 = new Htc(new Action(){
			public void doWalk() {
				System.out.println("Cat is walking");
			}
		});
		
		htc1.action.doWalk();
		htc2.action.doWalk();

	}
}