public static boolean isEmpty(String string) {
        return string == null || string.isEmpty();
    }
@Test
    public void testIsEmpty() {
        assertThat( Strings.isEmpty( null ) ).isTrue();
        assertThat( Strings.isEmpty( "" ) ).isTrue();
        assertThat( Strings.isEmpty( " " ) ).isFalse();
        assertThat( Strings.isEmpty( "not empty" ) ).isFalse();
    }