code: static public synchronized MessageMap getMessageMap(JSchema sfs, BigInteger code) {
      // This method must be synchronized since some of the work done when constructing
      // a new MessageMap is not thread safe.
      MessageMapTable maps = (MessageMapTable)sfs.getInterpreterCache(JMFRegistry.JMF_ENCODING_VERSION);
      if (maps == null) {
        BigInteger count = ((JSType)sfs.getJMFType()).getMultiChoiceCount();
        maps = new MessageMapTable(count);
        sfs.setInterpreterCache(JMFRegistry.JMF_ENCODING_VERSION, maps);
      }
      MessageMap ans = maps.getMap(code);
      if (ans == null)
        maps.set(ans = new MessageMap(sfs, code));
      return ans;
    }
docs: Method to retrieve (and possibly construct) the MessageMap for a particular
  multiChoice code