## ping ##### *Description* Check the current connection status 检查当前连接实例的状态 ##### *Parameters* (none) ##### *Return Value* *STRING*: `<span class="calibre12">+PONG</span>` on success. Throws a RedisException object on connectivity error, as described above. 如果失败，Throws一个RedisException对象报出连接错误。