### Question:
StringHelper { public boolean areFirstAndLastTwoCharactersTheSame(String str) { if (str.length() <= 1) return false; if (str.length() == 2) return true; String first2Chars = str.substring(0, 2); String last2Chars = str.substring(str.length() - 2); return first2Chars.equals(last2Chars); }  String truncateAInFirst2Positions(String str); boolean areFirstAndLastTwoCharactersTheSame(String str);  }### Answer:
@Test public void testAreFirstAndLastTwoCharactersTheSame_BasicNegativeScenario() { assertFalse( helper.areFirstAndLastTwoCharactersTheSame("ABCD")); }
@Test public void testAreFirstAndLastTwoCharactersTheSame_BasicPositiveScenario() { assertTrue( helper.areFirstAndLastTwoCharactersTheSame("ABAB")); }