### Question:
CharSequenceUtil { public static boolean isNotBlank(CharSequence charSequence) { return !isBlank(charSequence); }  static boolean isEmpty(CharSequence charSequence); static boolean isNotEmpty(CharSequence charSequence); static boolean isBlank(CharSequence charSequence); static boolean isNotBlank(CharSequence charSequence);  }### Answer:
@Test public void testIsNotBlank() { assertFalse(CharSequenceUtil.isNotBlank(null)); assertFalse(CharSequenceUtil.isNotBlank("")); assertFalse(CharSequenceUtil.isNotBlank(" ")); assertFalse(CharSequenceUtil.isNotBlank(" \t\n\r ")); assertTrue(CharSequenceUtil.isNotBlank("a")); assertTrue(CharSequenceUtil.isNotBlank(" a ")); }