code: function(params, callback) {
          if (!client) {
            fireEvent("error", {
              errorCode: 999,
              errorMessage: "ActiveMQ Client is not ready or has not been initialized!"
            });
          }
  
          var subscribeHeaders = {
            "destination": params.destination,
            "ack": params.ack
          };
  
          client.subscribe(subscribeHeaders, function(error, message) {
            if (error) {
              fireEvent("error", {
                errorCode: 999,
                errorMessage: "ActiveMQ Subscription Error!"
              });
              return;
            }
  
            message.readString("utf-8", function(error, body) {
              if (error) {
                fireEvent("error", {
                  errorCode: 999,
                  errorMessage: "ActiveMQ Read Message Error!"
                });
                return;
              }
  
              callback && callback(body);
  
              client.ack(message);
            });
          });
        }
docs: *****************************************************
  P R I V A T E   M E T H O D S            *
  *****************************************************