/**
* Copyright 2012 Apache Wave
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.waveprotocol.box.server.waveserver;
import com.google.common.base.Function;
import com.google.common.collect.HashMultimap;
import com.google.common.collect.MapMaker;
import com.google.common.collect.Multimap;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.SettableFuture;
import com.google.inject.Inject;
import com.google.inject.Singleton;
import org.waveprotocol.wave.model.id.WaveId;
import org.waveprotocol.wave.model.id.WaveletId;
import org.waveprotocol.wave.model.id.WaveletName;
import org.waveprotocol.wave.model.wave.ParticipantId;
import org.waveprotocol.wave.util.logging.Log;
import java.util.Map;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.TimeUnit;
/**
* @author yurize@apache.org (Yuri Zelikov)
*/
@Singleton
public class MemoryPerUserWaveViewHandlerImpl implements PerUserWaveViewHandler {
private static final Log LOG = Log.get(MemoryPerUserWaveViewHandlerImpl.class);
/**
* The period of time in minutes the per user waves view should be actively
* kept up to date after last access.
*/
private static final int PER_USER_WAVES_VIEW_CACHE_MINUTES = 5;
/** The computing map that holds wave viev per each online user.*/
public ConcurrentMap<ParticipantId, Multimap<WaveId, WaveletId>> explicitPerUserWaveViews;
@Inject
public MemoryPerUserWaveViewHandlerImpl(final WaveMap waveMap) {
// Let the view expire if it not accessed for some time.
explicitPerUserWaveViews =
new MapMaker().expireAfterAccess(PER_USER_WAVES_VIEW_CACHE_MINUTES, TimeUnit.MINUTES)
.makeComputingMap(new Function<ParticipantId, Multimap<WaveId, WaveletId>>() {
@Override
public Multimap<WaveId, WaveletId> apply(final ParticipantId user) {
Multimap<WaveId, WaveletId> userView = HashMultimap.create();
// Create initial per user waves view by looping over all waves
// in the waves store.
Map<WaveId, Wave> waves = waveMap.getWaves();
for (Map.Entry<WaveId, Wave> entry : waves.entrySet()) {
Wave wave = entry.getValue();
for (WaveletContainer c : wave) {
WaveletId waveletId = c.getWaveletName().waveletId;
try {
if (!c.hasParticipant(user)) {
continue;
}
// Add this wave to the user view.
userView.put(entry.getKey(), waveletId);
} catch (WaveletStateException e) {
LOG.warning("Failed to access wavelet " + c.getWaveletName(), e);
}
}
}
LOG.info("Initalized waves view for user: " + user.getAddress()
+ ", number of waves in view: " + userView.size());
return userView;
}
});
}
@Override
public ListenableFuture<Void> onParticipantAdded(WaveletName waveletName, ParticipantId user) {
if (explicitPerUserWaveViews.containsKey(user)) {
Multimap<WaveId, WaveletId> perUserView = explicitPerUserWaveViews.get(user);
if (!perUserView.containsEntry(waveletName.waveId, waveletName.waveletId)) {
perUserView.put(waveletName.waveId, waveletName.waveletId);
LOG.fine("Added wavelet: " + waveletName + " to the view of user: " + user.getAddress());
}
}
SettableFuture<Void> task = SettableFuture.create();
task.set(null);
return task;
}
@Override
public ListenableFuture<Void> onParticipantRemoved(WaveletName waveletName, ParticipantId user) {
if (explicitPerUserWaveViews.containsKey(user)) {
Multimap<WaveId, WaveletId> perUserView = explicitPerUserWaveViews.get(user);
if (perUserView.containsEntry(waveletName.waveId, waveletName.waveletId)) {
perUserView.remove(waveletName.waveId, waveletName.waveletId);
LOG.fine("Removed wavelet: " + waveletName
+ " from the view of user: " + user.getAddress());
}
}
SettableFuture<Void> task = SettableFuture.create();
task.set(null);
return task;
}
@Override
public Multimap<WaveId, WaveletId> retrievePerUserWaveView(ParticipantId user) {
return explicitPerUserWaveViews.get(user);
}
@Override
public ListenableFuture<Void> onWaveInit(WaveletName waveletName) {
// No op.
SettableFuture<Void> task = SettableFuture.create();
task.set(null);
return task;
}
}