/*
* 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.struts2.cdi;
import com.opensymphony.xwork2.ObjectFactory;
import com.opensymphony.xwork2.inject.Inject;
import com.opensymphony.xwork2.util.logging.Logger;
import com.opensymphony.xwork2.util.logging.LoggerFactory;
import javax.enterprise.context.spi.CreationalContext;
import javax.enterprise.inject.spi.BeanManager;
import javax.enterprise.inject.spi.InjectionTarget;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
/**
* CdiObjectFactory allows Struts 2 managed objects, like Actions, Interceptors or Results, to be injected by a Contexts
* and Dependency Injection container (JSR299 / WebBeans).
* The BeanManager instance will be searched in the container's JNDI context, according to following algorithm:
* <ul>
* <li>if a value for configuration constant <code>struts.objectFactory.cdi.jndiKey</code> is given, this key will be looked up</li>
* <li>if no BeanManager found so far, look under {@link #CDI_JNDIKEY_BEANMANAGER_COMP}</li>
* <li>if no BeanManager found so far, look under {@link #CDI_JNDIKEY_BEANMANAGER_APP}</li>
* <li>if no BeanManager found so far, look under {@link #CDI_JNDIKEY_BEANMANAGER_COMP_ENV}</li>
* </ul>
*/
public class CdiObjectFactory extends ObjectFactory {
private static final Logger LOG = LoggerFactory.getLogger(CdiObjectFactory.class);
/**
* The key under which the BeanManager can be found according to CDI API docs
*/
public static final String CDI_JNDIKEY_BEANMANAGER_COMP = "java:comp/BeanManager";
/**
* The key under which the BeanManager can be found according to JBoss Weld docs
*/
public static final String CDI_JNDIKEY_BEANMANAGER_APP = "java:app/BeanManager";
/**
* The key under which the BeanManager can be found in pure Servlet containers according to JBoss Weld docs.
*/
public static final String CDI_JNDIKEY_BEANMANAGER_COMP_ENV = "java:comp/env/BeanManager";
private String jndiKey;
@Inject(value = "struts.objectFactory.cdi.jndiKey", required = false)
public void setJndiKey( String jndiKey ) {
this.jndiKey = jndiKey;
}
protected BeanManager beanManager;
protected CreationalContext ctx;
Map<Class<?>, InjectionTarget<?>> injectionTargetCache = new ConcurrentHashMap<Class<?>, InjectionTarget<?>>();
public CdiObjectFactory() {
super();
LOG.info("Initializing Struts2 CDI integration...");
this.beanManager = findBeanManager();
if (beanManager != null) {
this.ctx = buildNonContextualCreationalContext(beanManager);
LOG.info("Struts2 CDI integration initialized.");
} else {
LOG.error("Struts2 CDI integration could not be initialized.");
}
}
/**
* Try to find the CDI BeanManager from JNDI context. First, if provided, the key given by
* struts.objectFactory.cdi.jndiKey will be checked. Then, if nothing was found or no explicit configuration was
* given, the key {@link #CDI_JNDIKEY_BEANMANAGER_COMP} will be tested. If nothing is found there, the key {@link
* #CDI_JNDIKEY_BEANMANAGER_APP} will be checked. If still nothing is found there, the key {@link
* #CDI_JNDIKEY_BEANMANAGER_COMP_ENV} will be checked.
*
* @return the BeanManager, if found. <tt>null</tt> otherwise.
*/
protected BeanManager findBeanManager() {
BeanManager bm = null;
try {
Context initialContext = new InitialContext();
if (jndiKey != null && jndiKey.trim().length() > 0) {
// Check explicit configuration first, if given
bm = lookup(initialContext, jndiKey);
}
if (bm == null) {
// Check CDI default
bm = lookup(initialContext, CDI_JNDIKEY_BEANMANAGER_COMP);
}
if (bm == null) {
// Check WELD default
bm = lookup(initialContext, CDI_JNDIKEY_BEANMANAGER_APP);
}
if (bm == null) {
// Check Tomcat / Jetty default
bm = lookup(initialContext, CDI_JNDIKEY_BEANMANAGER_COMP_ENV);
}
if (bm == null) {
if (LOG.isErrorEnabled()) {
LOG.error("[findBeanManager]: Could not find BeanManager instance for any given JNDI key, giving up");
}
}
} catch ( NamingException e ) {
if (LOG.isErrorEnabled()) {
LOG.error("[findBeanManager]: Unable to get InitialContext for BeanManager lookup", e);
}
}
return bm;
}
/**
* Lookup the given JNDI key in the given context.
*
* @param context the context to use for lookup.
* @param jndiKeyToCheck the key to lookup.
*
* @return the BeanManager, if found; <tt>null</tt> if not found or {@link javax.naming.NamingException} was thrown.
*/
protected BeanManager lookup( Context context, String jndiKeyToCheck ) {
if (LOG.isInfoEnabled()) {
LOG.info("[lookup]: Checking for BeanManager under JNDI key " + jndiKeyToCheck);
}
BeanManager result = null;
try {
result = (BeanManager) context.lookup(jndiKeyToCheck);
} catch ( NamingException e ) {
if (LOG.isDebugEnabled()) {
LOG.debug("[lookup]: BeanManager lookup failed for JNDI key " + jndiKeyToCheck, e);
}
}
return result;
}
@Override
@SuppressWarnings("unchecked")
public Object buildBean(String className, Map<String, Object> extraContext, boolean injectInternal)
throws Exception {
Class<?> clazz = getClassInstance(className);
InjectionTarget injectionTarget = getInjectionTarget(clazz);
Object o = injectionTarget.produce(ctx);
injectionTarget.inject(o, ctx);
injectionTarget.postConstruct(o);
if (injectInternal) {
injectInternalBeans(o);
}
return o;
}
/**
* Get a InjectionTarget instance for a given class. If the appropriate target is not found in cache, a nw instance
* will be created.
*
* @param clazz The class to get a InjectionTarget instance for.
* @return if found in cache, an existing instance. A new instance otherwise.
*/
protected InjectionTarget<?> getInjectionTarget(Class<?> clazz) {
InjectionTarget<?> result;
result = injectionTargetCache.get(clazz);
if (result == null) {
result = beanManager.createInjectionTarget(beanManager.createAnnotatedType(clazz));
injectionTargetCache.put(clazz, result);
}
return result;
}
/**
* Simple wrapper for CreationalContext creation.
*
* @param beanManager the BeanManager to use for creating the context.
* @return the context to use, if given BeanManager was not <tt>null</tt>. <tt>null</tt> otherwise.
*/
@SuppressWarnings("unchecked")
protected CreationalContext buildNonContextualCreationalContext(BeanManager beanManager) {
return beanManager != null ? beanManager.createCreationalContext(null) : null;
}
}