Void value as return parameter

Question

I have this interface:

public interface Command {
    T execute(String... args);
}

it works fine for most uses. But when I try to mode

Answer 1

What is interesting in your example is the use of parameterized types. Usually you'd have

interface Command {
    public T execute(T someObject);
}

In your case you only have T as a return value. Nevertheless using Void in this case is a good solution. The return value should be null.