Is making an empty string constant worth it?

Question

I have a co-worker that swears by

//in a singleton \"Constants\" class
public static final String EMPTY_STRING = \"\";

in a constants class

Answer 1

We just do the following for situations like this:

public class StaticUtils
{
    public static boolean empty(CharSequence cs)
    {
        return cs == null || cs.length() == 0;
    }

    public static boolean has(CharSequence cs)
    {
        return !empty(cs);
    }
}

Then just import static StaticUtils.*