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;
020
021import javax.faces.context.FacesContext;
022import javax.faces.event.PhaseEvent;
023import javax.faces.event.PhaseId;
024import javax.faces.event.PhaseListener;
025
026import org.springframework.beans.factory.BeanFactoryUtils;
027import org.springframework.beans.factory.ListableBeanFactory;
028import org.springframework.web.context.WebApplicationContext;
029
030/**
031 * JSF PhaseListener implementation that delegates to one or more Spring-managed
032 * PhaseListener beans coming from the Spring root WebApplicationContext.
033 *
034 * <p>Configure this listener multicaster in your {@code faces-config.xml} file
035 * as follows:
036 *
037 * <pre class="code">
038 * &lt;application&gt;
039 *   ...
040 *   &lt;phase-listener&gt;
041 *     org.springframework.web.jsf.DelegatingPhaseListenerMulticaster
042 *   &lt;/phase-listener&gt;
043 *   ...
044 * &lt;/application&gt;</pre>
045 *
046 * The multicaster will delegate all {@code beforePhase} and {@code afterPhase}
047 * events to all target PhaseListener beans. By default, those will simply be obtained
048 * by type: All beans in the Spring root WebApplicationContext that implement the
049 * PhaseListener interface will be fetched and invoked.
050 *
051 * <p>Note: This multicaster's {@code getPhaseId()} method will always return
052 * {@code ANY_PHASE}. <b>The phase id exposed by the target listener beans
053 * will be ignored; all events will be propagated to all listeners.</b>
054 *
055 * <p>This multicaster may be subclassed to change the strategy used to obtain
056 * the listener beans, or to change the strategy used to access the ApplicationContext
057 * (normally obtained via {@link FacesContextUtils#getWebApplicationContext(FacesContext)}).
058 *
059 * @author Juergen Hoeller
060 * @author Colin Sampaleanu
061 * @since 1.2.7
062 */
063@SuppressWarnings("serial")
064public class DelegatingPhaseListenerMulticaster implements PhaseListener {
065
066        @Override
067        public PhaseId getPhaseId() {
068                return PhaseId.ANY_PHASE;
069        }
070
071        @Override
072        public void beforePhase(PhaseEvent event) {
073                for (PhaseListener listener : getDelegates(event.getFacesContext())) {
074                        listener.beforePhase(event);
075                }
076        }
077
078        @Override
079        public void afterPhase(PhaseEvent event) {
080                for (PhaseListener listener : getDelegates(event.getFacesContext())) {
081                        listener.afterPhase(event);
082                }
083        }
084
085
086        /**
087         * Obtain the delegate PhaseListener beans from the Spring root WebApplicationContext.
088         * @param facesContext the current JSF context
089         * @return a Collection of PhaseListener objects
090         * @see #getBeanFactory
091         * @see org.springframework.beans.factory.ListableBeanFactory#getBeansOfType(Class)
092         */
093        protected Collection<PhaseListener> getDelegates(FacesContext facesContext) {
094                ListableBeanFactory bf = getBeanFactory(facesContext);
095                return BeanFactoryUtils.beansOfTypeIncludingAncestors(bf, PhaseListener.class, true, false).values();
096        }
097
098        /**
099         * Retrieve the Spring BeanFactory to delegate bean name resolution to.
100         * <p>The default implementation delegates to {@code getWebApplicationContext}.
101         * Can be overridden to provide an arbitrary ListableBeanFactory reference to
102         * resolve against; usually, this will be a full Spring ApplicationContext.
103         * @param facesContext the current JSF context
104         * @return the Spring ListableBeanFactory (never {@code null})
105         * @see #getWebApplicationContext
106         */
107        protected ListableBeanFactory getBeanFactory(FacesContext facesContext) {
108                return getWebApplicationContext(facesContext);
109        }
110
111        /**
112         * Retrieve the web application context to delegate bean name resolution to.
113         * <p>The default implementation delegates to FacesContextUtils.
114         * @param facesContext the current JSF context
115         * @return the Spring web application context (never {@code null})
116         * @see FacesContextUtils#getRequiredWebApplicationContext
117         */
118        protected WebApplicationContext getWebApplicationContext(FacesContext facesContext) {
119                return FacesContextUtils.getRequiredWebApplicationContext(facesContext);
120        }
121
122}