### Question:
StringUtil { public static Boolean isNotBlank(String string) { return !isBlank(string); }  static boolean isBlank(String string); static Boolean isNotBlank(String string);  }### Answer:
@Test public void shouldCheckIfAStringIsNotBlank() throws Exception { assertThat(StringUtil.isNotBlank(""), is(false)); assertThat(StringUtil.isNotBlank(" "), is(false)); assertThat(StringUtil.isNotBlank(null), is(false)); assertThat(StringUtil.isNotBlank(" a "), is(true)); }