Implementing interfaces in Groovy

This a quick post just to put some facts out there after i read this post.

In the post the Vita states that "In Groovy when your class implements a Java interface it must have all the methods present"

Well this is NOT exactly true. Here is an example below of me implementing only the interfaces i want:

This is my very simple interface with 3 methods;

public interface SaySomething {

 String saySomethingTrue();

 String saySomethingFalse();

 String saySomethingFunny();
}

In Groovy you easily implement a multi-method interface with a Map (method name = closure)

So i have code like this. I ONLY implement the methods i want.

SaySomething saySomething = [saySomethingTrue:{'Groovy rocks'},
                          saySomethingFalse:{'Groovy must implement all methods in a Java interface.'},] as SaySomething;

println "This is true:  "  + saySomething.saySomethingTrue();

println "This is false: "  + saySomething.saySomethingFalse();

As you can see in quick example above i don't provide an implementation for saySomethingFunny()

The result of running this is:

This is true:  Groovy rocks
This is false: Groovy must implement all methods in a Java interface.

UPDATE...

If you just want to do the same thing for all methods:

SaySomething saySomething2 = {return "I am handling all methods"} as SaySomething

println "This is true:  "  + saySomething2.saySomethingTrue();

println "This is false: "  + saySomething2.saySomethingFalse();

println "This is funny: "  + saySomething2.saySomethingFunny();

This prints out:

This is true:  I am handling all methods
This is false: I am handling all methods
This is funny: I am handling all methods