001/*
002 * Copyright 2002-2012 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.web.jsf;
018
019import java.util.Collection;
020import javax.faces.context.FacesContext;
021import javax.faces.event.PhaseEvent;
022import javax.faces.event.PhaseId;
023import javax.faces.event.PhaseListener;
024
025import org.springframework.beans.factory.BeanFactoryUtils;
026import org.springframework.beans.factory.ListableBeanFactory;
027import org.springframework.web.context.WebApplicationContext;
028
029/**
030 * JSF PhaseListener implementation that delegates to one or more Spring-managed
031 * PhaseListener beans coming from the Spring root WebApplicationContext.
032 *
033 * <p>Configure this listener multicaster in your {@code faces-config.xml} file
034 * as follows:
035 *
036 * <pre class="code">
037 * &lt;application&gt;
038 *   ...
039 *   &lt;phase-listener&gt;
040 *     org.springframework.web.jsf.DelegatingPhaseListenerMulticaster
041 *   &lt;/phase-listener&gt;
042 *   ...
043 * &lt;/application&gt;</pre>
044 *
045 * The multicaster will delegate all {@code beforePhase} and {@code afterPhase}
046 * events to all target PhaseListener beans. By default, those will simply be obtained
047 * by type: All beans in the Spring root WebApplicationContext that implement the
048 * PhaseListener interface will be fetched and invoked.
049 *
050 * <p>Note: This multicaster's {@code getPhaseId()} method will always return
051 * {@code ANY_PHASE}. <b>The phase id exposed by the target listener beans
052 * will be ignored; all events will be propagated to all listeners.</b>
053 *
054 * <p>This multicaster may be subclassed to change the strategy used to obtain
055 * the listener beans, or to change the strategy used to access the ApplicationContext
056 * (normally obtained via {@link FacesContextUtils#getWebApplicationContext(FacesContext)}).
057 *
058 * @author Juergen Hoeller
059 * @author Colin Sampaleanu
060 * @since 1.2.7
061 */
062@SuppressWarnings("serial")
063public class DelegatingPhaseListenerMulticaster implements PhaseListener {
064
065        @Override
066        public PhaseId getPhaseId() {
067                return PhaseId.ANY_PHASE;
068        }
069
070        @Override
071        public void beforePhase(PhaseEvent event) {
072                for (PhaseListener listener : getDelegates(event.getFacesContext())) {
073                        listener.beforePhase(event);
074                }
075        }
076
077        @Override
078        public void afterPhase(PhaseEvent event) {
079                for (PhaseListener listener : getDelegates(event.getFacesContext())) {
080                        listener.afterPhase(event);
081                }
082        }
083
084
085        /**
086         * Obtain the delegate PhaseListener beans from the Spring root WebApplicationContext.
087         * @param facesContext the current JSF context
088         * @return a Collection of PhaseListener objects
089         * @see #getBeanFactory
090         * @see org.springframework.beans.factory.ListableBeanFactory#getBeansOfType(Class)
091         */
092        protected Collection<PhaseListener> getDelegates(FacesContext facesContext) {
093                ListableBeanFactory bf = getBeanFactory(facesContext);
094                return BeanFactoryUtils.beansOfTypeIncludingAncestors(bf, PhaseListener.class, true, false).values();
095        }
096
097        /**
098         * Retrieve the Spring BeanFactory to delegate bean name resolution to.
099         * <p>The default implementation delegates to {@code getWebApplicationContext}.
100         * Can be overridden to provide an arbitrary ListableBeanFactory reference to
101         * resolve against; usually, this will be a full Spring ApplicationContext.
102         * @param facesContext the current JSF context
103         * @return the Spring ListableBeanFactory (never {@code null})
104         * @see #getWebApplicationContext
105         */
106        protected ListableBeanFactory getBeanFactory(FacesContext facesContext) {
107                return getWebApplicationContext(facesContext);
108        }
109
110        /**
111         * Retrieve the web application context to delegate bean name resolution to.
112         * <p>The default implementation delegates to FacesContextUtils.
113         * @param facesContext the current JSF context
114         * @return the Spring web application context (never {@code null})
115         * @see FacesContextUtils#getRequiredWebApplicationContext
116         */
117        protected WebApplicationContext getWebApplicationContext(FacesContext facesContext) {
118                return FacesContextUtils.getRequiredWebApplicationContext(facesContext);
119        }
120
121}