### Question:
ParamChecker { public static TimeZone checkTimeZone(String tzStr, String name) { TimeZone tz; try { tz = DateUtils.getTimeZone(tzStr); } catch (Exception ex) { throw new IllegalArgumentException(XLog.format("parameter [{0}] = [{1}] must be a valid TZ." + " Parsing error {2}", name, tzStr, ex.getMessage(), ex)); } return tz; }  static String notEmpty(String str, String name); static String notEmpty(String str, String name, String info); static List<String> notEmptyElements(List<String> list, String name); static String validateActionName(String actionName); static boolean isValidIdentifier(String token); static int checkGTZero(int value, String name); static int checkGEZero(int value, String name); static int checkLEZero(int value, String name); static int checkInteger(String val, String name); static String checkFrequency(String val); static Date checkDateOozieTZ(String date, String name); static TimeZone checkTimeZone(String tzStr, String name); static boolean isMember(String item, String[] members, String name);  }### Answer:
@Test public void testCheckTimeZone() { ParamChecker.checkTimeZone("UTC", "test"); try { ParamChecker.checkTimeZone("UTZ", "test"); fail(); } catch (Exception ex) { } ParamChecker.checkTimeZone("America/Los_Angeles", "test"); try { ParamChecker.checkTimeZone("America/Los_Angles", "test"); fail(); } catch (Exception ex) { } }