/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.jackrabbit.oak.jcr.observation;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.atomic.AtomicReference;
import javax.jcr.observation.Event;
import javax.jcr.observation.EventListener;
import org.apache.jackrabbit.commons.iterator.EventIteratorAdapter;
import org.apache.jackrabbit.oak.api.ChangeExtractor;
import org.apache.jackrabbit.oak.api.PropertyState;
import org.apache.jackrabbit.oak.commons.PathUtils;
import org.apache.jackrabbit.oak.namepath.NamePathMapper;
import org.apache.jackrabbit.oak.spi.state.ChildNodeEntry;
import org.apache.jackrabbit.oak.spi.state.NodeState;
import org.apache.jackrabbit.oak.spi.state.NodeStateDiff;
import org.apache.jackrabbit.oak.spi.state.NodeStateUtils;
import com.google.common.base.Function;
import com.google.common.collect.Iterators;
class ChangeProcessor implements Runnable {
private final ObservationManagerImpl observationManager;
private final NamePathMapper namePathMapper;
private final ChangeExtractor changeExtractor;
private final EventListener listener;
private final AtomicReference<ChangeFilter> filterRef;
public ChangeProcessor(ObservationManagerImpl observationManager, EventListener listener, ChangeFilter filter) {
this.observationManager = observationManager;
this.namePathMapper = observationManager.getNamePathMapper();
this.changeExtractor = observationManager.getChangeExtractor();
this.listener = listener;
filterRef = new AtomicReference<ChangeFilter>(filter);
}
public void setFilter(ChangeFilter filter) {
filterRef.set(filter);
}
@Override
public void run() {
EventGeneratingNodeStateDiff diff = new EventGeneratingNodeStateDiff();
changeExtractor.getChanges(diff);
observationManager.setHasEvents();
diff.sendEvents();
}
//------------------------------------------------------------< private >---
private class EventGeneratingNodeStateDiff implements NodeStateDiff {
public static final int PURGE_LIMIT = 8192;
private final String path;
private final NodeState associatedParentNode;
private int childNodeCount;
private List<Iterator<Event>> events;
EventGeneratingNodeStateDiff(String path, List<Iterator<Event>> events, NodeState associatedParentNode) {
this.path = path;
this.associatedParentNode = associatedParentNode;
this.events = events;
}
public EventGeneratingNodeStateDiff() {
this("/", new ArrayList<Iterator<Event>>(PURGE_LIMIT), null);
}
public void sendEvents() {
Iterator<Event> eventIt = Iterators.concat(events.iterator());
if (eventIt.hasNext()) {
listener.onEvent(new EventIteratorAdapter(eventIt));
events = new ArrayList<Iterator<Event>>(PURGE_LIMIT);
}
}
private String jcrPath() {
return namePathMapper.getJcrPath(path);
}
@Override
public void propertyAdded(PropertyState after) {
if (filterRef.get().include(Event.PROPERTY_ADDED, jcrPath(), associatedParentNode)) {
Event event = generatePropertyEvent(Event.PROPERTY_ADDED, path, after);
events.add(Iterators.singletonIterator(event));
}
}
@Override
public void propertyChanged(PropertyState before, PropertyState after) {
if (filterRef.get().include(Event.PROPERTY_CHANGED, jcrPath(), associatedParentNode)) {
Event event = generatePropertyEvent(Event.PROPERTY_CHANGED, path, after);
events.add(Iterators.singletonIterator(event));
}
}
@Override
public void propertyDeleted(PropertyState before) {
if (filterRef.get().include(Event.PROPERTY_REMOVED, jcrPath(), associatedParentNode)) {
Event event = generatePropertyEvent(Event.PROPERTY_REMOVED, path, before);
events.add(Iterators.singletonIterator(event));
}
}
@Override
public void childNodeAdded(String name, NodeState after) {
if (NodeStateUtils.isHidden(name)) {
return;
}
if (filterRef.get().includeChildren(jcrPath())) {
Iterator<Event> events = generateNodeEvents(Event.NODE_ADDED, path, name, after);
this.events.add(events);
if (++childNodeCount > PURGE_LIMIT) {
sendEvents();
}
}
}
@Override
public void childNodeDeleted(String name, NodeState before) {
if (NodeStateUtils.isHidden(name)) {
return;
}
if (filterRef.get().includeChildren(jcrPath())) {
Iterator<Event> events = generateNodeEvents(Event.NODE_REMOVED, path, name, before);
this.events.add(events);
}
}
@Override
public void childNodeChanged(String name, NodeState before, NodeState after) {
if (NodeStateUtils.isHidden(name)) {
return;
}
if (filterRef.get().includeChildren(jcrPath())) {
EventGeneratingNodeStateDiff diff = new EventGeneratingNodeStateDiff(
PathUtils.concat(path, name), events, after);
after.compareAgainstBaseState(before, diff);
if (events.size() > PURGE_LIMIT) {
diff.sendEvents();
}
}
}
private Event generatePropertyEvent(int eventType, String parentPath, PropertyState property) {
String jcrPath = namePathMapper.getJcrPath(PathUtils.concat(parentPath, property.getName()));
// TODO support userId, identifier, info, date
return new EventImpl(eventType, jcrPath, null, null, null, 0);
}
private Iterator<Event> generateNodeEvents(int eventType, String parentPath, String name, NodeState node) {
ChangeFilter filter = filterRef.get();
final String path = PathUtils.concat(parentPath, name);
String jcrParentPath = namePathMapper.getJcrPath(parentPath);
String jcrPath = namePathMapper.getJcrPath(path);
Iterator<Event> nodeEvent;
if (filter.include(eventType, jcrParentPath, associatedParentNode)) {
// TODO support userId, identifier, info, date
Event event = new EventImpl(eventType, jcrPath, null, null, null, 0);
nodeEvent = Iterators.singletonIterator(event);
} else {
nodeEvent = Iterators.emptyIterator();
}
final int propertyEventType = eventType == Event.NODE_ADDED
? Event.PROPERTY_ADDED
: Event.PROPERTY_REMOVED;
Iterator<Event> propertyEvents;
if (filter.include(propertyEventType, jcrPath, associatedParentNode)) {
propertyEvents = Iterators.transform(
node.getProperties().iterator(),
new Function<PropertyState, Event>() {
@Override
public Event apply(PropertyState property) {
return generatePropertyEvent(propertyEventType, path, property);
}
});
} else {
propertyEvents = Iterators.emptyIterator();
}
Iterator<Event> childNodeEvents = filter.includeChildren(jcrPath)
? Iterators.concat(generateChildEvents(eventType, path, node))
: Iterators.<Event>emptyIterator();
return Iterators.concat(nodeEvent, propertyEvents, childNodeEvents);
}
private Iterator<Iterator<Event>> generateChildEvents(final int eventType, final String parentPath, NodeState node) {
return Iterators.transform(
node.getChildNodeEntries().iterator(),
new Function<ChildNodeEntry, Iterator<Event>>() {
@Override
public Iterator<Event> apply(ChildNodeEntry entry) {
return generateNodeEvents(eventType, parentPath, entry.getName(), entry.getNodeState());
}
});
}
}
}