What's an example of duck typing in Java?

Question

I just recently heard of duck typing and I read the Wikipedia article about it, but I'm having a hard time translating the examples into Java, which would really help my understanding.

Would anyone be able to give a clear example of duck typing in Java and how I might possibly use it?

Answer 1

Java is by design not fit for duck typing. The way you might choose to do it is reflection:

public void doSomething(Object obj) throws Exception {

    obj.getClass().getMethod("getName", new Class<?>[] {}).invoke(obj);
}

But I would advocate doing it in a dynamic language, such as Groovy, where it makes more sense:

class Duck {
    quack() { println "I am a Duck" }
}

class Frog {
    quack() { println "I am a Frog" }
}

quackers = [ new Duck(), new Frog() ]
for (q in quackers) {
    q.quack()
}

Reference