001/* 002 * Copyright 2002-2013 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.orm.jdo.support; 018 019import javax.jdo.PersistenceManager; 020import javax.jdo.PersistenceManagerFactory; 021 022import org.apache.commons.logging.Log; 023import org.apache.commons.logging.LogFactory; 024 025import org.springframework.dao.DataAccessException; 026import org.springframework.orm.jdo.PersistenceManagerFactoryUtils; 027import org.springframework.orm.jdo.PersistenceManagerHolder; 028import org.springframework.transaction.support.TransactionSynchronizationManager; 029import org.springframework.ui.ModelMap; 030import org.springframework.web.context.request.WebRequest; 031import org.springframework.web.context.request.WebRequestInterceptor; 032 033/** 034 * Spring web request interceptor that binds a JDO PersistenceManager to the 035 * thread for the entire processing of the request. Intended for the "Open 036 * PersistenceManager in View" pattern, i.e. to allow for lazy loading in 037 * web views despite the original transactions already being completed. 038 * 039 * <p>This interceptor makes JDO PersistenceManagers available via the current thread, 040 * which will be autodetected by transaction managers. It is suitable for service 041 * layer transactions via {@link org.springframework.orm.jdo.JdoTransactionManager} 042 * or {@link org.springframework.transaction.jta.JtaTransactionManager} as well 043 * as for non-transactional read-only execution. 044 * 045 * <p>In contrast to {@link OpenPersistenceManagerInViewFilter}, this interceptor 046 * is set up in a Spring application context and can thus take advantage of 047 * bean wiring. 048 * 049 * @author Juergen Hoeller 050 * @since 1.1 051 * @see OpenPersistenceManagerInViewFilter 052 * @see org.springframework.orm.jdo.JdoTransactionManager 053 * @see org.springframework.orm.jdo.PersistenceManagerFactoryUtils#getPersistenceManager 054 * @see org.springframework.transaction.support.TransactionSynchronizationManager 055 */ 056public class OpenPersistenceManagerInViewInterceptor implements WebRequestInterceptor { 057 058 /** 059 * Suffix that gets appended to the PersistenceManagerFactory toString 060 * representation for the "participate in existing persistence manager 061 * handling" request attribute. 062 * @see #getParticipateAttributeName 063 */ 064 public static final String PARTICIPATE_SUFFIX = ".PARTICIPATE"; 065 066 067 protected final Log logger = LogFactory.getLog(getClass()); 068 069 private PersistenceManagerFactory persistenceManagerFactory; 070 071 072 /** 073 * Set the JDO PersistenceManagerFactory that should be used to create 074 * PersistenceManagers. 075 */ 076 public void setPersistenceManagerFactory(PersistenceManagerFactory pmf) { 077 this.persistenceManagerFactory = pmf; 078 } 079 080 /** 081 * Return the JDO PersistenceManagerFactory that should be used to create 082 * PersistenceManagers. 083 */ 084 public PersistenceManagerFactory getPersistenceManagerFactory() { 085 return persistenceManagerFactory; 086 } 087 088 089 @Override 090 public void preHandle(WebRequest request) throws DataAccessException { 091 if (TransactionSynchronizationManager.hasResource(getPersistenceManagerFactory())) { 092 // Do not modify the PersistenceManager: just mark the request accordingly. 093 String participateAttributeName = getParticipateAttributeName(); 094 Integer count = (Integer) request.getAttribute(participateAttributeName, WebRequest.SCOPE_REQUEST); 095 int newCount = (count != null ? count + 1 : 1); 096 request.setAttribute(getParticipateAttributeName(), newCount, WebRequest.SCOPE_REQUEST); 097 } 098 else { 099 logger.debug("Opening JDO PersistenceManager in OpenPersistenceManagerInViewInterceptor"); 100 PersistenceManager pm = 101 PersistenceManagerFactoryUtils.getPersistenceManager(getPersistenceManagerFactory(), true); 102 TransactionSynchronizationManager.bindResource( 103 getPersistenceManagerFactory(), new PersistenceManagerHolder(pm)); 104 } 105 } 106 107 @Override 108 public void postHandle(WebRequest request, ModelMap model) { 109 } 110 111 @Override 112 public void afterCompletion(WebRequest request, Exception ex) throws DataAccessException { 113 String participateAttributeName = getParticipateAttributeName(); 114 Integer count = (Integer) request.getAttribute(participateAttributeName, WebRequest.SCOPE_REQUEST); 115 if (count != null) { 116 // Do not modify the PersistenceManager: just clear the marker. 117 if (count > 1) { 118 request.setAttribute(participateAttributeName, count - 1, WebRequest.SCOPE_REQUEST); 119 } 120 else { 121 request.removeAttribute(participateAttributeName, WebRequest.SCOPE_REQUEST); 122 } 123 } 124 else { 125 PersistenceManagerHolder pmHolder = (PersistenceManagerHolder) 126 TransactionSynchronizationManager.unbindResource(getPersistenceManagerFactory()); 127 logger.debug("Closing JDO PersistenceManager in OpenPersistenceManagerInViewInterceptor"); 128 PersistenceManagerFactoryUtils.releasePersistenceManager( 129 pmHolder.getPersistenceManager(), getPersistenceManagerFactory()); 130 } 131 } 132 133 /** 134 * Return the name of the request attribute that identifies that a request is 135 * already filtered. Default implementation takes the toString representation 136 * of the PersistenceManagerFactory instance and appends ".FILTERED". 137 * @see #PARTICIPATE_SUFFIX 138 */ 139 protected String getParticipateAttributeName() { 140 return getPersistenceManagerFactory().toString() + PARTICIPATE_SUFFIX; 141 } 142 143}