org.tango.server.events.DeviceInterfaceChangedSender Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of JTangoServer Show documentation
Library for Tango Server (ie. Tango Device) in Java
There is a newer version: 10.0.0
/**
 * Copyright (C) :     2012
 * 
 * Synchrotron Soleil
 * L'Orme des merisiers
 * Saint Aubin
 * BP48
 * 91192 GIF-SUR-YVETTE CEDEX
 * 

 * This file is part of Tango.
 * 

 * Tango is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 

 * Tango is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with Tango.  If not, see .
 */
package org.tango.server.events;

import fr.esrf.Tango.DevFailed;
import fr.esrf.Tango.DevIntrChange;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.tango.server.Constants;
import org.tango.server.ServerManager;
import org.tango.utils.DevFailedUtils;

import java.util.concurrent.*;

public class DeviceInterfaceChangedSender {
    private final Logger logger = LoggerFactory.getLogger(DeviceInterfaceChangedSender.class);
    private final String deviceName;
    private final EventSenderTask task;
    private ExecutorService executor;
    private Future future;

    public DeviceInterfaceChangedSender(final String deviceName) {
        this.deviceName = deviceName;
        task = new EventSenderTask(deviceName);
        executor = Executors.newFixedThreadPool(1, new ThreadFactory() {
            @Override
            public Thread newThread(final Runnable r) {
                return new Thread(r, "DeviceInterfaceChangedSender-" + deviceName);
            }
        });
    }

    public synchronized void pushEvent(final DevIntrChange deviceInterface, final boolean isStarted) {
        if (isStarted) { // device startup, send event and empty queue
            if (!deviceName.equalsIgnoreCase(Constants.ADMIN_DEVICE_DOMAIN + "/"
                    + ServerManager.getInstance().getServerName())) {
                task.clear();
                logger.debug("send event for interface changed of {}", deviceName);
                try {
                    EventManager.getInstance().pushInterfaceChangedEvent(deviceName, deviceInterface);
                } catch (final DevFailed e) {
                    logger.error(DevFailedUtils.toString(e));
                    logger.error("impossible to send event", e);
                }
            }
        } else {
            // queue event
            logger.debug("request for interface changed of {} queued", deviceName);
            task.add(deviceInterface);
            if (future == null && EventManager.getInstance().hasSubscriber(deviceName)) {
                future = executor.submit(task);
            }
        }

    }

    public synchronized void stop() {
        task.clear();
        if (future != null) {
            future.cancel(true);
            future = null;
        }
    }

    private class EventSenderTask implements Runnable {
        private final LinkedBlockingDeque interfaces = new LinkedBlockingDeque(1);
        private final String deviceName;

        public EventSenderTask(final String deviceName) {
            this.deviceName = deviceName;
        }

        public void add(final DevIntrChange deviceInterface) {
            interfaces.clear();
            interfaces.add(deviceInterface);
        }

        public void clear() {
            interfaces.clear();
        }

        @Override
        public void run() {
            boolean stop = false;
            while (!stop && EventManager.getInstance().hasSubscriber(deviceName)) {
                try {
                    final DevIntrChange devInterface = interfaces.take();
                    EventManager.getInstance().pushInterfaceChangedEvent(deviceName, devInterface);
                    Thread.sleep(50);
                } catch (final InterruptedException e) {
                    Thread.currentThread().interrupt();
                    stop = true;
                } catch (final DevFailed e) {
                    logger.error(DevFailedUtils.toString(e));
                    logger.error("impossible to send event", e);
                }
            }
        }
    }
}