code: public static final DateIntervalFormat getInstance(String skeleton,
                                                   Locale locale, 
                                                   DateIntervalInfo dtitvinf)
      {
          return getInstance(skeleton, ULocale.forLocale(locale), dtitvinf);
      }
docs: Construct a DateIntervalFormat from skeleton
  a DateIntervalInfo, and the given locale.
  
  This is a convenient override of
  getInstance(String skeleton, ULocale locale, DateIntervalInfo dtitvinf)
  
  <p>Example code:{@sample external/icu/android_icu4j/src/samples/java/android/icu/samples/text/dateintervalformat/DateIntervalFormatSample.java dtitvfmtCustomizedExample}
  @param skeleton  the skeleton on which interval format based.
  @param locale    the given locale
  @param dtitvinf  the DateIntervalInfo object to be adopted.
  @return          a date time interval formatter.