### Question:
NmeaUtil { static boolean isValidFieldCharacter(char ch) { return ch <= 127 && ch >= 32 && !invalidFieldCharacters.contains((int) ch); } private  NmeaUtil(); static boolean isValid(String sentence); static String getChecksum(String sentence); static String getChecksum(String sentence, boolean ignoreLeadingDollarOrExclamation); static NmeaMessage parseNmea(String line); static String insertKeyValueInTagBlock(String line, String name, String value); static String supplementWithTime(String line, long arrivalTime); static Talker getTalker(String s); static String createTagBlock(LinkedHashMap<String, String> tags); static String createNmeaLine(LinkedHashMap<String, String> tags, List<String> items);  }### Answer:
@Test public void testIsValidFieldCharacter() { assertFalse(NmeaUtil.isValidFieldCharacter((char) 0)); assertFalse(NmeaUtil.isValidFieldCharacter((char) 31)); assertTrue(NmeaUtil.isValidFieldCharacter((char) 32)); assertFalse(NmeaUtil.isValidFieldCharacter((char) 33)); assertFalse(NmeaUtil.isValidFieldCharacter((char) 36)); assertFalse(NmeaUtil.isValidFieldCharacter((char) 126)); assertFalse(NmeaUtil.isValidFieldCharacter((char) 127)); assertFalse(NmeaUtil.isValidFieldCharacter((char) 128)); }