code: static synchronized String getTimeZoneDisplay(TimeZone tz, boolean daylight, int style, Locale locale) {
          Object key = new TimeZoneDisplayKey(tz, daylight, style, locale);
          String value = (String) cTimeZoneDisplayCache.get(key);
          if (value == null) {
              // This is a very slow call, so cache the results.
              value = tz.getDisplayName(daylight, style, locale);
              cTimeZoneDisplayCache.put(key, value);
          }
          return value;
      }
docs: <p>Gets the time zone display name, using a cache for performance.</p>
  
  @param tz  the zone to query
  @param daylight  true if daylight savings
  @param style  the style to use <code>TimeZone.LONG</code>
  or <code>TimeZone.SHORT</code>
  @param locale  the locale to use
  @return the textual name of the time zone