code: @Override public synchronized Long zadd(final String key, final ZsetPair scoremember, final ZsetPair ... scoresmembers) throws WrongTypeException {
          checkType(key, "zset");
          Long count = 0L;
          if (!zsetCache.exists(key) || !zsetCache.get(key).contains(scoremember.member)) {
              ++count;
          }
          zsetCache.set(key, scoremember.member, scoremember.score);
          for (ZsetPair sms : scoresmembers) {
              if (sms == null) {
                  continue;
              }
              if (!zsetCache.get(key).contains(sms.member)) {
                  ++count;
              }
              zsetCache.set(key, sms.member, sms.score);
          }
          return count;
      }
docs: /* IRedisSortedSet commands