### Question:
StringHelper { public static boolean isStringEmptyOrNull(String str) { return str == null || str.isEmpty(); }  static boolean isStringEmptyOrNull(String str); static String escapeRex(String rex); static String repeat(String a, int max);  }### Answer:
@SuppressWarnings("ConstantConditions") @Test void testStringEmptyOrNull() { assertTrue(StringHelper.isStringEmptyOrNull(null)); assertTrue(StringHelper.isStringEmptyOrNull("")); assertFalse(StringHelper.isStringEmptyOrNull("test")); }