code: function Service(manager, name, port, heartbeat) {
    var _name = name;
    /**
     * @property {String} name The name of the service
     */
    Object.defineProperty(this, 'name', {
      get: function get() {
        return _name;
      },
      enumerable: true
    });
    var _port = port;
    /**
     * @property {Number} port The port claimed by the service
     */
    Object.defineProperty(this, 'port', {
      get: function get() {
        return _port;
      },
      enumerable: true
    });
    var _heartbeatInterval;
    if (heartbeat !== 0) {
      debug('set heartbeat %d', heartbeat);
      _heartbeatInterval = setInterval(heartbeatTest.call(this, manager), heartbeat);
    }
    /**
     * @property {Number} heartbeat The heartbeat counter for the periodic port checking
     */
    Object.defineProperty(this, 'heartbeat', {
      get: function get() {
        return _heartbeatInterval;
      }
    });
  }
docs: The service to manage
  
  @class node_modules.port_manager.Service
  @param {Manager} manager The manager instance that store all services
  @param {String} name The name of the service
  @param {Number} port The port claimed by the service
  @param {Number} [heartbeat] The heartbeat timer
  @constructor