Constructs a new {@link ListTokenSource} instance from the specified
collection of {@link Token} objects.
@param tokens The collection of {@link Token} objects to provide as a
{@link TokenSource}.
@exception NullPointerException if {@code tokens} is {@code null}
Constructs a new {@link ListTokenSource} instance from the specified collection of {@link Token} objects.
@param tokens The collection of {@link Token} objects to provide as a {@link TokenSource}. @exception NullPointerException if {@code tokens} is {@code null}