### Question:
GenderConverter { public String convert(String gender) { return GENDER_TYPE_MAP.get(gender); }  String convert(String gender);  }### Answer:
@Test public void testNullObject() { String result = converter.convert(null); Assert.assertNull("Race list should be null", result); }
@Test public void testMale() { String result = converter.convert("M"); Assert.assertEquals("Male", result); }
@Test public void testFemale() { String result = converter.convert("F"); Assert.assertEquals("Female", result); }
@Test public void testUnknown() { String result = converter.convert("U"); Assert.assertNull(result); }