Implementing an interface with two abstract methods by a lambda expression

Question

In Java 8 the lambda expression is introduced to help with the reduction of boilerplate code. If the interface has only one method it works fine. I

Answer 1

You can always use composition:

public inteface I1 {
    void show1();
    void show2();
}

public class I1Adapter {
    private final Runnable r1,r2;
    public I1Adapter(Runnable r1, Runnable r2) {this.r1=r1; this.r2=r2;}
    public void show1() {r1.run();}
    public void show2() {r2.run();}
    public static I1Adapter compose(Runnable r1, Runnable r2) {
        return new I1Adapter(r1,r2);
    }
}

No you can do (with a static import):

I1 i1 = compose(()->foo(), ()->bar());