### Question:
Strings { public static boolean isEmptyOrWhitespace(String s) { return (s == null) || (s.trim().length() == 0); }  static boolean isEmptyOrWhitespace(String s); static String fromStream(InputStream inputStream); static InputStream asStream(String string);  }### Answer:
@Test public void testIsEmptyOrWhitespace() { assertThat(isEmptyOrWhitespace(""), equalTo(true)); assertThat(isEmptyOrWhitespace(" "), equalTo(true)); assertThat(isEmptyOrWhitespace(" \n \t "), equalTo(true)); assertThat(isEmptyOrWhitespace("foo"), equalTo(false)); assertThat(isEmptyOrWhitespace(" bar "), equalTo(false)); assertThat(isEmptyOrWhitespace(" \tbar \n"), equalTo(false)); }