/*
* WBI Indicator Explorer
*
* Copyright 2015 Sebastian Nogara <snogaraleal@gmail.com>
*
* This file is part of WBI.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package client.managers.models.watcher;
import java.util.ArrayList;
import java.util.List;
import com.google.gwt.user.client.Timer;
import rpc.client.ClientRequest;
import models.Indicator;
import client.services.WBIManagementService;
/**
* Implementation of {@link IndicatorWatcher} that polls the server for
* changes in {@link Indicator} objects.
*/
public class PollingIndicatorWatcher extends IndicatorWatcher {
/**
* Default value for {@code interval}.
*/
public static final int DEFAULT_INTERVAL = 2000;
/**
* Time in milliseconds between each request.
*/
private int interval;
/**
* {@code ClientRequest.Listener} handling RPC responses.
*/
private ClientRequest.Listener<List<Indicator>> pollRequestListener;
/**
* Timer in charge of making requests periodically.
*/
private Timer timer;
/**
* Initialize {@code PollingIndicatorWatcher}.
*
* @param interval Time in milliseconds between each request.
*/
public PollingIndicatorWatcher(int interval) {
super();
this.interval = interval;
/*
* Initialize RPC handler.
*/
pollRequestListener = new ClientRequest.Listener<List<Indicator>>() {
@Override
public void onSuccess(List<Indicator> indicators) {
for (Indicator indicator : indicators) {
change(indicator);
}
}
@Override
public void onFailure(ClientRequest.Error error) {
}
};
/*
* Initialize polling timer.
*/
timer = new Timer() {
@Override
public void run() {
if (!watched.isEmpty()) {
List<Long> indicatorIds = new ArrayList<Long>();
for (Indicator indicator : watched.keySet()) {
indicatorIds.add(indicator.getId());
}
WBIManagementService.poll(
indicatorIds, pollRequestListener);
}
}
};
}
/**
* Initialize {@code PollingIndicatorWatcher} with the default interval.
*/
public PollingIndicatorWatcher() {
this(DEFAULT_INTERVAL);
}
@Override
public void start() {
timer.scheduleRepeating(interval);
}
@Override
public void stop() {
timer.cancel();
}
}