code: public void setUpperCaseFirst(boolean upperfirst) {
          checkNotFrozen();
          if (upperfirst == isUpperCaseFirst()) { return; }
          CollationSettings ownedSettings = getOwnedSettings();
          ownedSettings.setCaseFirst(upperfirst ? CollationSettings.CASE_FIRST_AND_UPPER_MASK : 0);
          setFastLatinOptions(ownedSettings);
      }
docs: Sets whether uppercase characters sort before lowercase characters or vice versa, in strength TERTIARY. The
  default mode is false, and so lowercase characters sort before uppercase characters. If true, sort upper case
  characters first.
  
  @param upperfirst
  true to sort uppercase characters before lowercase characters, false to sort lowercase characters
  before uppercase characters
  @see #isLowerCaseFirst
  @see #isUpperCaseFirst
  @see #setLowerCaseFirst
  @see #setCaseFirstDefault