org.apache.causeway.persistence.jdo.spring.support.OpenPersistenceManagerInViewFilter Maven / Gradle / Ivy
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/*
* 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.causeway.persistence.jdo.spring.support;
import java.io.IOException;
import javax.jdo.PersistenceManager;
import javax.jdo.PersistenceManagerFactory;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.transaction.support.TransactionSynchronizationManager;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import org.springframework.web.filter.OncePerRequestFilter;
import org.apache.causeway.persistence.jdo.spring.integration.PersistenceManagerFactoryUtils;
import org.apache.causeway.persistence.jdo.spring.integration.PersistenceManagerHolder;
/**
* Servlet Filter that binds a JDO PersistenceManager to the thread for the
* entire processing of the request. Intended for the "Open PersistenceManager in
* View" pattern, i.e. to allow for lazy loading in web views despite the
* original transactions already being completed.
*
* This filter makes JDO PersistenceManagers available via the current thread,
* which will be autodetected by transaction managers. It is suitable for service
* layer transactions via {@link org.apache.causeway.persistence.jdo.spring.integration.JdoTransactionManager}
* or {@link org.springframework.transaction.jta.JtaTransactionManager} as well
* as for non-transactional read-only execution.
*
*
Looks up the PersistenceManagerFactory in Spring's root web application context.
* Supports a "persistenceManagerFactoryBeanName" filter init-param in {@code web.xml};
* the default bean name is "persistenceManagerFactory".
*
* @see OpenPersistenceManagerInViewInterceptor
* @see org.apache.causeway.persistence.jdo.spring.integration.JdoTransactionManager
* @see org.apache.causeway.persistence.jdo.spring.integration.PersistenceManagerFactoryUtils#getPersistenceManager
* @see org.springframework.transaction.support.TransactionSynchronizationManager
*/
public class OpenPersistenceManagerInViewFilter extends OncePerRequestFilter {
public static final String DEFAULT_PERSISTENCE_MANAGER_FACTORY_BEAN_NAME = "persistenceManagerFactory";
private String persistenceManagerFactoryBeanName = DEFAULT_PERSISTENCE_MANAGER_FACTORY_BEAN_NAME;
/**
* Set the bean name of the PersistenceManagerFactory to fetch from Spring's
* root application context. Default is "persistenceManagerFactory".
* @see #DEFAULT_PERSISTENCE_MANAGER_FACTORY_BEAN_NAME
*/
public void setPersistenceManagerFactoryBeanName(String persistenceManagerFactoryBeanName) {
this.persistenceManagerFactoryBeanName = persistenceManagerFactoryBeanName;
}
/**
* Return the bean name of the PersistenceManagerFactory to fetch from Spring's
* root application context.
*/
protected String getPersistenceManagerFactoryBeanName() {
return this.persistenceManagerFactoryBeanName;
}
/**
* Returns "false" so that the filter may re-bind the opened {@code PersistenceManager}
* to each asynchronously dispatched thread and postpone closing it until the very
* last asynchronous dispatch.
*/
@Override
protected boolean shouldNotFilterAsyncDispatch() {
return false;
}
/**
* Returns "false" so that the filter may provide an {@code PersistenceManager}
* to each error dispatches.
*/
@Override
protected boolean shouldNotFilterErrorDispatch() {
return false;
}
@Override
protected void doFilterInternal(
HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
throws ServletException, IOException {
PersistenceManagerFactory pmf = lookupPersistenceManagerFactory(request);
boolean participate = false;
if (TransactionSynchronizationManager.hasResource(pmf)) {
// Do not modify the PersistenceManager: just set the participate flag.
participate = true;
}
else {
logger.debug("Opening JDO PersistenceManager in OpenPersistenceManagerInViewFilter");
PersistenceManager pm = PersistenceManagerFactoryUtils.getPersistenceManager(pmf, true);
TransactionSynchronizationManager.bindResource(pmf, new PersistenceManagerHolder(pm));
}
try {
filterChain.doFilter(request, response);
}
finally {
if (!participate) {
PersistenceManagerHolder pmHolder = (PersistenceManagerHolder)
TransactionSynchronizationManager.unbindResource(pmf);
logger.debug("Closing JDO PersistenceManager in OpenPersistenceManagerInViewFilter");
PersistenceManagerFactoryUtils.releasePersistenceManager(pmHolder.getPersistenceManager(), pmf);
}
}
}
/**
* Look up the PersistenceManagerFactory that this filter should use,
* taking the current HTTP request as argument.
*
Default implementation delegates to the {@code lookupPersistenceManagerFactory}
* without arguments.
* @return the PersistenceManagerFactory to use
* @see #lookupPersistenceManagerFactory()
*/
protected PersistenceManagerFactory lookupPersistenceManagerFactory(HttpServletRequest request) {
return lookupPersistenceManagerFactory();
}
/**
* Look up the PersistenceManagerFactory that this filter should use.
* The default implementation looks for a bean with the specified name
* in Spring's root application context.
* @return the PersistenceManagerFactory to use
* @see #getPersistenceManagerFactoryBeanName
*/
protected PersistenceManagerFactory lookupPersistenceManagerFactory() {
if (logger.isDebugEnabled()) {
logger.debug("Using PersistenceManagerFactory '" + getPersistenceManagerFactoryBeanName() +
"' for OpenPersistenceManagerInViewFilter");
}
WebApplicationContext wac = WebApplicationContextUtils.getRequiredWebApplicationContext(getServletContext());
return wac.getBean(getPersistenceManagerFactoryBeanName(), PersistenceManagerFactory.class);
}
}