code: public String pipelineReadHGETALL(String key, String hm_key_prefix) throws Exception {
          DynoJedisPipeline pipeline = jedisClient.get().pipelined();
          Response<Map<byte[], byte[]>> resp = pipeline.hgetAll((hm_key_prefix + key).getBytes());
          pipeline.sync();
          if (resp == null || resp.get() == null) {
              logger.info("Cache Miss: key:" + key);
              return null;
          } else {
              StringBuilder sb = new StringBuilder();
              for (byte[] bytes : resp.get().keySet()) {
                  if (sb.length() > 0) {
                      sb.append(",");
                  }
                  sb.append(new String(bytes));
              }
              return "HGETALL:" + sb.toString();
          }
      }
docs: This the pipelined HGETALL
  
  @param key
  @return the contents of the hash
  @throws Exception