### Question:
PhoneNumber { public static boolean isValid(PhoneNumber phoneNumber) { return phoneNumber != null && !EMPTY_PHONE_NUMBER.equals(phoneNumber) && !TextUtils .isEmpty(phoneNumber.getPhoneNumber()) && !TextUtils.isEmpty(phoneNumber .getCountryCode()) && !TextUtils.isEmpty(phoneNumber.getCountryIso()); } PhoneNumber(String phoneNumber, String countryIso, String countryCode); static PhoneNumber emptyPhone(); String getCountryCode(); String getPhoneNumber(); String getCountryIso(); static boolean isValid(PhoneNumber phoneNumber); static boolean isCountryValid(PhoneNumber phoneNumber);  }### Answer:
@Test public void testIsValid_nullPhone() throws Exception { assertFalse(PhoneNumber.isValid(null)); }
@Test public void testIsValid_emptyMembers() throws Exception { PhoneNumber invalidPhoneNumber = new PhoneNumber("", PhoneTestConstants.US_ISO2, PhoneTestConstants .US_COUNTRY_CODE); assertFalse(PhoneNumber.isValid(invalidPhoneNumber)); invalidPhoneNumber = new PhoneNumber(PhoneTestConstants.PHONE, "", PhoneTestConstants .US_COUNTRY_CODE); assertFalse(PhoneNumber.isValid(invalidPhoneNumber)); invalidPhoneNumber = new PhoneNumber(PhoneTestConstants.PHONE, PhoneTestConstants.US_ISO2, ""); assertFalse(PhoneNumber.isValid(invalidPhoneNumber)); }
@Test public void testIsValid() throws Exception { final PhoneNumber validPhoneNumber = new PhoneNumber(PhoneTestConstants.PHONE, PhoneTestConstants .US_ISO2, PhoneTestConstants.US_COUNTRY_CODE); assertTrue(PhoneNumber.isValid(validPhoneNumber)); }