示例#1
0
 /** PV is connected. Get meta info, or subscribe right away. */
 private void handleConnected(final Channel channel) {
   try {
     if (channel.getConnectionState() != Channel.CONNECTED) {
       return;
     }
   } catch (Exception ex) {
     logger.warn("Exception handling connection state change for " + this.name, ex);
     return;
   }
   if (state == PVConnectionState.Connected) return;
   state = PVConnectionState.Connected;
   hostName = channel_ref.getChannel().getHostName();
   totalMetaInfo.setHostName(hostName);
   for (final PVListener listener : listeners) {
     listener.pvConnected(this);
   }
   // If we're "running", we need to get the meta data and
   // then subscribe.
   // Otherwise, we're done.
   if (!running) {
     connected = true;
     // meta = null;
     synchronized (this) {
       this.notifyAll();
     }
     return;
   }
   // else: running, get meta data, then subscribe
   try {
     DBRType type = channel.getFieldType();
     if (!(plain || type.isSTRING())) {
       state = PVConnectionState.GettingMetadata;
       if (type.isDOUBLE() || type.isFLOAT()) type = DBRType.CTRL_DOUBLE;
       else if (type.isENUM()) type = DBRType.LABELS_ENUM;
       else if (type.isINT()) type = DBRType.CTRL_INT;
       else type = DBRType.CTRL_SHORT;
       channel.get(type, 1, meta_get_listener);
       return;
     }
   } catch (final Exception ex) {
     logger.error("exception when handleConnect " + name, ex);
     return;
   }
   // Meta info is not requested, not available for this type,
   // or there was an error in the get call.
   // So reset it, then just move on to the subscription.
   // meta = null;
   subscribe();
 }
示例#2
0
  /** @param channelName */
  public void execute(String channelName) {

    try {

      // initialize context
      initialize();

      // Create the Channel to connect to the PV.
      Channel channel = context.createChannel(channelName);

      // Send the request and wait 5.0 seconds for the channel to connect to the PV.
      context.pendIO(5.0);

      // If we're here, then everything went fine.
      // Display basic information about the channel.
      channel.printInfo();

      /** ***************************************************************** */
      /** *************************** sync get **************************** */
      /** ***************************************************************** */
      System.out.println("\n------------------------------------------------\n");
      System.out.println("Sync get:");

      // get request w/o callbacks will wait until flush/pendIO is called
      // (channel default 'type' and 'count' is used)
      DBR dbr = channel.get();
      context.pendIO(3.0);
      dbr.printInfo();

      System.out.println();

      dbr = channel.get(DBRType.STRING, 1);
      context.pendIO(3.0);
      String[] value = ((STRING) dbr).getStringValue();
      System.out.println("Read string value: " + value[0]);

      /** ***************************************************************** */
      /** ************************** async get **************************** */
      /** ***************************************************************** */
      System.out.println("\n------------------------------------------------\n");
      System.out.println("Async get:");

      // get request w/ callbacks are always issued immediately
      // not related to pendIO at all, but require pend_event (to be flushed also)
      GetListenerImpl listener = new GetListenerImpl();
      channel.get(listener);
      synchronized (listener) {
        // flush & get event back
        context.flushIO();
        // wait for response...
        listener.wait(3000);
      }

      if (listener.getStatus() == CAStatus.NORMAL) listener.getValue().printInfo();
      else System.err.println("Get error: " + listener.getStatus());

      /** ***************************************************************** */
      /** *************************** Monitors **************************** */
      /** ***************************************************************** */
      System.out.println("\n------------------------------------------------\n");
      System.out.println("Monitors:");
      System.out.println();

      // Create a monitor
      Monitor monitor = channel.addMonitor(Monitor.VALUE, new MonitorListenerImpl());
      context.flushIO();

      // Sleep for 10 seconds (monitors will be printed out).
      Thread.sleep(10000);

      // Clear the monitor
      monitor.clear();

      System.out.println("\n------------------------------------------------");

      /** ***************************************************************** */
      /** ***************************************************************** */
      /** ***************************************************************** */

      // Disconnect the channel.
      channel.destroy();

      // Flush all pending requests...
      context.flushIO();

      System.out.println("Done.");

    } catch (Throwable th) {
      th.printStackTrace();
    } finally {
      // always finalize
      destroy();
    }
  }