server.java

这是一个分布式通信程序框架源程序

     *
     *     public void Update(String aString)
     *     {
     *         this.setString(0, aString);
     *         updateService(service_id);
     *     }
     * }
     * </pre></blockquote>
     *
     */

    public static native int    addService(String serviceName, String serviceType, DataEncoder theNativeDataEncoder);

    // Note: we do not define an addService() method with a Memory parameter.
    // Specifying only a method with a Memory type parameter, would not alow us to be informed when data is
    // required. (Alowing the data to be tailored to the requesting user).
    // If a Memory type parameter is beneficial for efficiency reasons, then the responsability for maintaining
    // such a permanent reference to the Memory object can be given to the class implementing the DataEncoder.
    // Example: see the class dim.test.StringService

    /**
     * adds a named command service to the server.
     * @param commandName The name by which this command will be registered in the Dim Name Space (DNS) registry.
     * @param commandType The type of the service, specifying the data format.
     * @param theNativeDataDecoder An object that implements the DataDecoder interface and that
     * will digest the Native data from a client command.
     * @return The service registration ID.
     */
    public static native int    addCommand(String commandName, String commandType, DataDecoder theNativeDataDecoder);

//  void add_client_exit_handler(void (*usr_routine)(...));
//  void set_client_exit_handler(int conn_id, int tag);
//  void add_exit_handler(void (*usr_routine)(...));
//  void report_service(char *service_name);

    /**
     * Signals a specific client.
     * @param service_id The service identification that was returned when the service was registered.
     * @param client_id The internal connection number (as returned
     * by get_client_connID() ) of the client that is to be notified.
     */
    public static int  selectiveUpdateService(int serviceId, int clientId) { return selectiveUpdateService(serviceId, new int[] {clientId, 0});}

    /**
     * Signals a selective list of clients.
     * @param service_id The service identification that was returned when the service was registered.
     * @param client_id_list The list that contains the internal connection number (as returned
     * by get_client_connID() ) of the clients that are to be notified. Note: the last element of the list should
     * contain zero.
     */
    public static native int  selectiveUpdateService(int serviceId, int[] clientIdList);

    /**
     * Signals all subscribing clients of the service.
     * @param service_id The service identification that was returned when the service was registered.
     */
    public static        int  updateService(int serviceId) { return selectiveUpdateService(serviceId, null); }

    /**
     * removes a previously registered information or command service.
     * @param service_id The service identification that was returned when the service was registered.
     */

	public static native void  noPadding();
	
	public static native int  removeService(int serviceId);

    /** @todo look at these not implemented server functions
      * int    get_next_cmnd(int *tag, int *buffer, int *size );
      *        public static native int find_service(string name);
      * void add_client_exit_handler(void (*usr_routine)(...));
      * void set_client_exit_handler(int conn_id, int tag);
      * void add_exit_handler(void (*usr_routine)(...));
      * void report_service(char *service_name);
      * void send_service(int service_id, int *buffer, int size);	// where is this used?
      * int  set_buffer_size(int size);
      * void set_quality(int service_id, int quality);
      * void set_timestamp(int service_id, int secs, int millisecs);
      * void disable_padding();
     */

    /**
     * A simple class that provides an Object Oriented wrapper around the add_service function.
     * <p>
     * This class may in a future release be extended with convenience methods to inquire on
     * properties such as name, connected clients, buffers etc.
     * <p>
     * In a future version this class will be extended with an autmatic call to remove the service once there
     * are no more references to this class. To ensure continuation of the serivce, the user should keep
     * a reference to this class as long as its services are required.
     * <br>For performance and stability reasons, however, the user is encouraged to use the remove method
     * explicitly and not to rely on the automatic clean up facility (which is not actually implemented).
     * @see #addService
     * @todo implement a getStatus method  etc.
     */
    public static class Info
    {
        /**
         * The service_id off the service.
         */
        private int serviceId;

        /**
         * Creates a new instance of a info service.
         * @param serviceName The name by which this service will be registered in the Dim Name Space (DNS) registry.
         * @param serviceType The type of the service, specifying the data format.
         * @param theNativeDataEncoder An object that implements the DataEncoder interface and that
         * will cook the Native data on request for a client.
         * @see #addService addService
         */
        public Info(String serviceName, String serviceType, DataEncoder theNativeDataEncoder)
        {
            serviceId = addService(serviceName, serviceType, theNativeDataEncoder);
        }


        /**
         * Signals all subscribing clients of the service.
         */
        public void update()
        {
            updateService(serviceId);
        }


        /**
         * Signals a selected client only.
         * @param client_id The internal connection number (as returned
         * by get_client_connID() ) of the client that should be notified.
         */
        public void selectiveUpdate(int clientId)
        {
            selectiveUpdateService(serviceId, new int[] {clientId, 0});
        }

        /**
         * Signals a selective list of clients.
         * @param client_id_list The list that contains the internal connection number (as returned
         * by get_client_connID() ) of the clients that are to be notified.
         */
        public void selectiveUpdate(int[] clientIdList)
        {
            selectiveUpdateService(serviceId, clientIdList);
        }

        /**
         * Removes the registered service.
         */
        public void remove()
        {
            removeService(serviceId);
        }
    }


    /**
     * A simple class that provides an Object Oriented wrapper around the add_cmnd function.
     * <p>
     * This class may in a future release be extended with convenience methods to inquire on
     * properties such as name, connected clients, buffers etc.
     * <p>
     * In a future version this class will be extended with an autmatic call to remove the service once there
     * are no more references to this class. To ensure continuation of the serivce, the user should keep
     * a reference to this class as long as its services are required.
     * <br>For performance and stability reasons, however, the user is encouraged to use the remove method
     * explicitly and not to rely on the automatic clean up facility (which is not actually implemented).
     * @see #addCommand
     * @todo implement a getStatus method  etc.
     */
    public static class Command
    {
        /**
         * The service_id off the service.
         */
        private int serviceId;

        /**
         * Creates a new instance of command service to the server.
         * @param commandName The name by which this command will be registered in the Dim Name Space (DNS) registry.
         * @param serviceType The type of the service, specifying the data format.
         * @param theNativeDataDecoder An object that implements the DataDecoder interface and that
         * will digest the Native data from a client command.
         * @see #addCommand addCommand
         */
        public Command(String commandName, String commandType, DataDecoder theNativeDataDecoder)
        {
            serviceId = addCommand(commandName, commandType, theNativeDataDecoder);
        }

        /**
         * Removes the registered service.
         */
        public void remove()
        {
            removeService(serviceId);
        }
    }

}