com.sun.faces.application.applicationimpl.Events Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jakarta.faces Show documentation
Show all versions of jakarta.faces Show documentation
EE4J Compatible Implementation for Jakarta Faces API
The newest version!
/*
* Copyright (c) 1997, 2020 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package com.sun.faces.application.applicationimpl;
import static com.sun.faces.util.Util.notNull;
import static jakarta.faces.application.ProjectStage.Development;
import static java.util.logging.Level.WARNING;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.logging.Logger;
import com.sun.faces.application.applicationimpl.events.ComponentSystemEventHelper;
import com.sun.faces.application.applicationimpl.events.EventInfo;
import com.sun.faces.application.applicationimpl.events.ReentrantLisneterInvocationGuard;
import com.sun.faces.application.applicationimpl.events.SystemEventHelper;
import com.sun.faces.util.FacesLogger;
import jakarta.faces.application.ProjectStage;
import jakarta.faces.component.UIViewRoot;
import jakarta.faces.context.FacesContext;
import jakarta.faces.event.AbortProcessingException;
import jakarta.faces.event.ExceptionQueuedEvent;
import jakarta.faces.event.ExceptionQueuedEventContext;
import jakarta.faces.event.SystemEvent;
import jakarta.faces.event.SystemEventListener;
import jakarta.faces.event.SystemEventListenerHolder;
public class Events {
private static final Logger LOGGER = FacesLogger.APPLICATION.getLogger();
private static final String CONTEXT = "context";
private static final String LISTENER = "listener";
private static final String SOURCE = "source";
private static final String SYSTEM_EVENT_CLASS = "systemEventClass";
private final SystemEventHelper systemEventHelper = new SystemEventHelper();
private final ComponentSystemEventHelper compSysEventHelper = new ComponentSystemEventHelper();
/*
* This class encapsulates the behavior to prevent infinite loops when the publishing of one event leads to the queueing
* of another event of the same type. Special provision is made to allow the case where this guaring mechanims happens
* on a per-FacesContext, per-SystemEvent.class type basis.
*/
private final ReentrantLisneterInvocationGuard listenerInvocationGuard = new ReentrantLisneterInvocationGuard();
/*
* @see jakarta.faces.application.Application#publishEvent(FacesContext, Class, Class, Object)
*/
public void publishEvent(FacesContext context, Class systemEventClass, Class sourceBaseType, Object source,
ProjectStage projectStage) {
notNull(CONTEXT, context);
notNull(SYSTEM_EVENT_CLASS, systemEventClass);
notNull(SOURCE, source);
if (!needsProcessing(context, systemEventClass)) {
return;
}
// Source is not compatible with the provided base type.
// Log a warning that the types are incompatible and return.
if (projectStage == Development && sourceBaseType != null && !sourceBaseType.isInstance(source)) {
if (LOGGER.isLoggable(WARNING)) {
LOGGER.log(WARNING, "faces.application.publish.event.base_type_mismatch", new Object[] { source.getClass().getName(), sourceBaseType.getName() });
}
return;
}
try {
// The side-effect of calling invokeListenersFor
// will create a SystemEvent object appropriate to event/source
// combination. This event will be passed on subsequent invocations
// of invokeListenersFor
// Look for and invoke any listeners stored on the source instance.
SystemEvent event = invokeComponentListenersFor(systemEventClass, source);
// Look for and invoke any 'view' listeners
event = invokeViewListenersFor(context, systemEventClass, event, source);
// Look for and invoke any listeners stored on the application using source type.
event = invokeListenersFor(systemEventClass, event, source, sourceBaseType, true);
// Look for and invoke any listeners not specific to the source class
invokeListenersFor(systemEventClass, event, source, null, false);
} catch (AbortProcessingException ape) {
context.getApplication().publishEvent(context, ExceptionQueuedEvent.class, new ExceptionQueuedEventContext(context, ape));
}
}
/*
* @see Application#subscribeToEvent(Class, jakarta.faces.event.SystemEventListener)
*/
public void subscribeToEvent(Class systemEventClass, SystemEventListener listener) {
subscribeToEvent(systemEventClass, null, listener);
}
/*
* @see Application#subscribeToEvent(Class, Class, jakarta.faces.event.SystemEventListener)
*/
public void subscribeToEvent(Class systemEventClass, Class sourceClass, SystemEventListener listener) {
notNull(SYSTEM_EVENT_CLASS, systemEventClass);
notNull(LISTENER, listener);
getListeners(systemEventClass, sourceClass).add(listener);
}
/*
* @see Application#unsubscribeFromEvent(Class, Class, jakarta.faces.event.SystemEventListener)
*/
public void unsubscribeFromEvent(Class systemEventClass, Class sourceClass, SystemEventListener listener) {
notNull(SYSTEM_EVENT_CLASS, systemEventClass);
notNull(LISTENER, listener);
Set listeners = getListeners(systemEventClass, sourceClass);
if (listeners != null) {
listeners.remove(listener);
}
}
/**
* @return the SystemEventListeners that should be used for the provided combination of SystemEvent and source.
*/
private Set getListeners(Class systemEvent, Class sourceClass) {
Set listeners = null;
EventInfo sourceInfo = systemEventHelper.getEventInfo(systemEvent, sourceClass);
if (sourceInfo != null) {
listeners = sourceInfo.getListeners();
}
return listeners;
}
private boolean needsProcessing(FacesContext context, Class systemEventClass) {
return context.isProcessingEvents() || ExceptionQueuedEvent.class.isAssignableFrom(systemEventClass);
}
/**
* @return process any listeners for the specified SystemEventListenerHolder and return any SystemEvent that may have
* been created as a side-effect of processing the listeners.
*/
private SystemEvent invokeComponentListenersFor(Class systemEventClass, Object source) {
if (source instanceof SystemEventListenerHolder) {
List listeners = ((SystemEventListenerHolder) source).getListenersForEventClass(systemEventClass);
if (null == listeners) {
return null;
}
EventInfo eventInfo = compSysEventHelper.getEventInfo(systemEventClass, source.getClass());
return processListeners(listeners, null, source, eventInfo);
}
return null;
}
private SystemEvent invokeViewListenersFor(FacesContext ctx, Class systemEventClass, SystemEvent event, Object source) {
SystemEvent result = event;
if (listenerInvocationGuard.isGuardSet(ctx, systemEventClass)) {
return result;
}
listenerInvocationGuard.setGuard(ctx, systemEventClass);
UIViewRoot root = ctx.getViewRoot();
try {
if (root != null) {
List listeners = root.getViewListenersForEventClass(systemEventClass);
if (null == listeners) {
return null;
}
EventInfo rootEventInfo = systemEventHelper.getEventInfo(systemEventClass, UIViewRoot.class);
// process view listeners
result = processListenersAccountingForAdds(listeners, event, source, rootEventInfo);
}
} finally {
listenerInvocationGuard.clearGuard(ctx, systemEventClass);
}
return result;
}
/**
* Traverse the List of listeners and invoke any that are relevent for the specified source.
*
* @throws jakarta.faces.event.AbortProcessingException propagated from the listener invocation
*/
private SystemEvent invokeListenersFor(Class systemEventClass, SystemEvent event, Object source, Class sourceBaseType,
boolean useSourceLookup) throws AbortProcessingException {
EventInfo eventInfo = systemEventHelper.getEventInfo(systemEventClass, source, sourceBaseType, useSourceLookup);
if (eventInfo != null) {
Set listeners = eventInfo.getListeners();
event = processListeners(listeners, event, source, eventInfo);
}
return event;
}
/**
* Iterate through and invoke the listeners. If the passed event was null, create the event, and return it.
*/
private SystemEvent processListeners(Collection listeners, SystemEvent event, Object source, EventInfo eventInfo) {
if (listeners != null && !listeners.isEmpty()) {
ArrayList list = new ArrayList<>(listeners);
for (SystemEventListener curListener : list) {
if (curListener != null && curListener.isListenerForSource(source)) {
if (event == null) {
event = eventInfo.createSystemEvent(source);
}
assert event != null;
if (event.isAppropriateListener(curListener)) {
event.processListener(curListener);
}
}
}
}
return event;
}
private SystemEvent processListenersAccountingForAdds(List listeners, SystemEvent event, Object source, EventInfo eventInfo) {
if (listeners != null && !listeners.isEmpty()) {
// copy listeners
// go thru copy completely
// compare copy to original
// if original differs from copy, make a new copy.
// The new copy consists of the original list - processed
SystemEventListener[] listenersCopy = new SystemEventListener[listeners.size()];
int i = 0;
for (i = 0; i < listenersCopy.length; i++) {
listenersCopy[i] = listeners.get(i);
}
Map processedListeners = new HashMap<>(listeners.size());
boolean processedSomeEvents = false, originalDiffersFromCopy = false;
do {
i = 0;
originalDiffersFromCopy = false;
if (0 < listenersCopy.length) {
for (i = 0; i < listenersCopy.length; i++) {
SystemEventListener curListener = listenersCopy[i];
if (curListener != null && curListener.isListenerForSource(source)) {
if (event == null) {
event = eventInfo.createSystemEvent(source);
}
assert event != null;
if (!processedListeners.containsKey(curListener) && event.isAppropriateListener(curListener)) {
processedSomeEvents = true;
event.processListener(curListener);
processedListeners.put(curListener, Boolean.TRUE);
}
}
}
if (originalDiffersFromCopy(listeners, listenersCopy)) {
originalDiffersFromCopy = true;
listenersCopy = copyListWithExclusions(listeners, processedListeners);
}
}
} while (originalDiffersFromCopy && processedSomeEvents);
}
return event;
}
private boolean originalDiffersFromCopy(Collection original, SystemEventListener[] copy) {
boolean foundDifference = false;
int i = 0, originalLen = original.size(), copyLen = copy.length;
if (originalLen == copyLen) {
SystemEventListener originalItem, copyItem;
Iterator iter = original.iterator();
while (iter.hasNext() && !foundDifference) {
originalItem = iter.next();
copyItem = copy[i++];
foundDifference = originalItem != copyItem;
}
} else {
foundDifference = true;
}
return foundDifference;
}
private SystemEventListener[] copyListWithExclusions(Collection original, Map excludes) {
SystemEventListener[] result = null, temp = new SystemEventListener[original.size()];
int i = 0;
for (SystemEventListener cur : original) {
if (!excludes.containsKey(cur)) {
temp[i++] = cur;
}
}
result = new SystemEventListener[i];
System.arraycopy(temp, 0, result, 0, i);
return result;
}
}