/*
* 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.jcr2spi.observation;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.jcr.RepositoryException;
import javax.jcr.observation.EventJournal;
import javax.jcr.observation.EventListener;
import javax.jcr.observation.EventListenerIterator;
import javax.jcr.observation.ObservationManager;
import org.apache.jackrabbit.commons.iterator.EventListenerIteratorAdapter;
import org.apache.jackrabbit.jcr2spi.WorkspaceManager;
import org.apache.jackrabbit.jcr2spi.nodetype.NodeTypeRegistry;
import org.apache.jackrabbit.spi.EventBundle;
import org.apache.jackrabbit.spi.EventFilter;
import org.apache.jackrabbit.spi.Name;
import org.apache.jackrabbit.spi.Path;
import org.apache.jackrabbit.spi.Event;
import org.apache.jackrabbit.spi.commons.conversion.NameException;
import org.apache.jackrabbit.spi.commons.conversion.NamePathResolver;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* <code>ObservationManagerImpl</code>...
*/
public class ObservationManagerImpl implements ObservationManager, InternalEventListener {
/**
* The logger instance for this class.
*/
private static final Logger log = LoggerFactory.getLogger(ObservationManagerImpl.class);
/**
* The workspace manager.
*/
private final WorkspaceManager wspManager;
/**
* The name and path resolver associated with the session this observation
* manager belongs to.
*/
private final NamePathResolver resolver;
/**
* The <code>NodeTypeRegistry</code> of the session.
*/
private final NodeTypeRegistry ntRegistry;
/**
* Live mapping of <code>EventListener</code> to <code>EventFilter</code>.
*/
private final Map<EventListener, EventFilter> subscriptions = new HashMap<EventListener, EventFilter>();
/**
* A read only mapping of <code>EventListener</code> to <code>EventFilter</code>.
*/
private Map<EventListener, EventFilter> readOnlySubscriptions;
/**
* Creates a new observation manager for <code>session</code>.
*
* @param wspManager the WorkspaceManager.
* @param resolver the name path resolver for this session.
* @param ntRegistry The <code>NodeTypeRegistry</code> of the session.
*/
public ObservationManagerImpl(WorkspaceManager wspManager,
NamePathResolver resolver,
NodeTypeRegistry ntRegistry) {
this.wspManager = wspManager;
this.resolver = resolver;
this.ntRegistry = ntRegistry;
}
/**
* @inheritDoc
*/
public void addEventListener(EventListener listener,
int eventTypes,
String absPath,
boolean isDeep,
String[] uuids,
String[] nodeTypeNames,
boolean noLocal) throws RepositoryException {
EventFilter filter = createEventFilter(eventTypes, absPath,
isDeep, uuids, nodeTypeNames, noLocal);
synchronized (subscriptions) {
subscriptions.put(listener, filter);
readOnlySubscriptions = null;
}
if (subscriptions.size() == 1) {
wspManager.addEventListener(this);
} else {
wspManager.updateEventFilters();
}
}
/**
* @inheritDoc
*/
public void removeEventListener(EventListener listener) throws RepositoryException {
synchronized (subscriptions) {
if (subscriptions.remove(listener) != null) {
readOnlySubscriptions = null;
}
}
if (subscriptions.size() == 0) {
wspManager.removeEventListener(this);
} else {
wspManager.updateEventFilters();
}
}
/**
* @inheritDoc
*/
public EventListenerIterator getRegisteredEventListeners() throws RepositoryException {
Map<EventListener, EventFilter> activeListeners;
synchronized (subscriptions) {
ensureReadOnlyMap();
activeListeners = readOnlySubscriptions;
}
return new EventListenerIteratorAdapter(activeListeners.keySet());
}
/**
* @see javax.jcr.observation.ObservationManager#getEventJournal()
*/
public EventJournal getEventJournal() throws RepositoryException {
return getEventJournal(Event.ALL_TYPES, "/", true, null, null);
}
/**
* @see javax.jcr.observation.ObservationManager#getEventJournal(int, String, boolean, String[], String[])
*/
public EventJournal getEventJournal(
int eventTypes, String absPath, boolean isDeep,
String[] uuid, String[] nodeTypeName)
throws RepositoryException {
EventFilter filter = createEventFilter(eventTypes, absPath, isDeep, uuid, nodeTypeName, false);
return new EventJournalImpl(wspManager, filter, resolver);
}
/**
* @see javax.jcr.observation.ObservationManager#setUserData(String)
*/
public void setUserData(String userData) throws RepositoryException {
wspManager.setUserData(userData);
}
//-----------------------< InternalEventListener >--------------------------
public Collection<EventFilter> getEventFilters() {
List<EventFilter> filters = new ArrayList<EventFilter>();
synchronized (subscriptions) {
ensureReadOnlyMap();
filters.addAll(readOnlySubscriptions.values());
}
return filters;
}
public void onEvent(EventBundle eventBundle) {
// get active listeners
Map<EventListener, EventFilter> activeListeners;
synchronized (subscriptions) {
ensureReadOnlyMap();
activeListeners = readOnlySubscriptions;
}
for (Map.Entry<EventListener, EventFilter> entry : activeListeners.entrySet()) {
EventListener listener = entry.getKey();
EventFilter filter = entry.getValue();
FilteredEventIterator eventIter = new FilteredEventIterator(
eventBundle.getEvents(), eventBundle.isLocal(), filter,
resolver, wspManager.getIdFactory());
if (eventIter.hasNext()) {
try {
listener.onEvent(eventIter);
} catch (Throwable t) {
log.warn("EventConsumer threw exception: " + t.toString());
log.debug("Stacktrace: ", t);
// move on to the next listener
}
}
}
}
//-------------------------< internal >-------------------------------------
/**
* Ensures that {@link #readOnlySubscriptions} is set. Callers of this
* method must own {@link #subscriptions} as a monitor to avoid concurrent
* access to {@link #subscriptions}.
*/
private void ensureReadOnlyMap() {
if (readOnlySubscriptions == null) {
readOnlySubscriptions = new HashMap<EventListener, EventFilter>(subscriptions);
}
}
/**
* Creates an SPI event filter from the given list of constraints.
*
* @param eventTypes the event types.
* @param absPath an absolute path.
* @param isDeep whether to include events for descendant items of
* the node at absPath.
* @param uuids uuid filters.
* @param nodeTypeNames node type filters.
* @param noLocal whether to exclude changes from the local session.
* @return the SPI event filter instance.
* @throws RepositoryException if an error occurs while creating the event
* filter.
*/
private EventFilter createEventFilter(int eventTypes,
String absPath,
boolean isDeep,
String[] uuids,
String[] nodeTypeNames,
boolean noLocal)
throws RepositoryException {
Path path;
try {
path = resolver.getQPath(absPath).getCanonicalPath();
} catch (NameException e) {
throw new RepositoryException("Malformed path: " + absPath);
}
// create NodeType instances from names
Name[] qNodeTypeNames;
if (nodeTypeNames == null) {
qNodeTypeNames = null;
} else {
try {
qNodeTypeNames = new Name[nodeTypeNames.length];
for (int i = 0; i < nodeTypeNames.length; i++) {
Name ntName = resolver.getQName(nodeTypeNames[i]);
if (!ntRegistry.isRegistered(ntName)) {
throw new RepositoryException("unknown node type: " + nodeTypeNames[i]);
}
qNodeTypeNames[i] = ntName;
}
} catch (NameException e) {
throw new RepositoryException(e.getMessage());
}
}
return wspManager.createEventFilter(eventTypes, path, isDeep,
uuids, qNodeTypeNames, noLocal);
}
}