Add Strings.nonEmpty(String)

Please add the following function to Strings in order to allow testing for non-empty strings in Streams or Optionals:

public static boolean nonEmpty(@Nullable String s) {
    return s != null && !s.isEmpty();
}

This follows the pattern of Objects.nonNull.

[perceptron8]

Duplicate of #3064?

[jrtom]

I can understand wanting to do that, but I think it’s highly unlikely that the Guava team is going to introduce a new method whose semantics are the negation of an existing method to save people from having to do this:

filter(s -> !isNullOrEmpty(s))

I mean, method references are nifty but lambdas make this pretty painless IMO.