001 /**
002 * Copyright 2005-2014 The Kuali Foundation
003 *
004 * Licensed under the Educational Community 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 * http://www.opensource.org/licenses/ecl2.php
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 package org.kuali.rice.krad.service.impl;
017
018 import com.thoughtworks.xstream.XStream;
019 import com.thoughtworks.xstream.converters.MarshallingContext;
020 import com.thoughtworks.xstream.converters.SingleValueConverter;
021 import com.thoughtworks.xstream.converters.reflection.ObjectAccessException;
022 import com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider;
023 import com.thoughtworks.xstream.converters.reflection.ReflectionConverter;
024 import com.thoughtworks.xstream.converters.reflection.ReflectionProvider;
025 import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
026 import com.thoughtworks.xstream.mapper.Mapper;
027 import org.apache.commons.logging.Log;
028 import org.apache.commons.logging.LogFactory;
029 import org.apache.ojb.broker.core.proxy.ListProxyDefaultImpl;
030 import org.joda.time.DateTime;
031 import org.joda.time.format.ISODateTimeFormat;
032 import org.kuali.rice.krad.service.KRADServiceLocator;
033 import org.kuali.rice.krad.service.PersistenceService;
034 import org.kuali.rice.krad.service.XmlObjectSerializerService;
035 import org.kuali.rice.krad.service.util.DateTimeConverter;
036
037 import java.lang.reflect.Field;
038 import java.util.ArrayList;
039 import java.util.Iterator;
040
041
042 /**
043 * Service implementation for the XmlObjectSerializer structure. This is the default implementation that gets
044 * delivered with Kuali. It utilizes the XStream open source libraries and framework.
045 *
046 * @author Kuali Rice Team (rice.collab@kuali.org)
047 */
048 public class XmlObjectSerializerServiceImpl implements XmlObjectSerializerService {
049 private static final Log LOG = LogFactory.getLog(XmlObjectSerializerServiceImpl.class);
050
051 private PersistenceService persistenceService;
052
053 private XStream xstream;
054
055 public XmlObjectSerializerServiceImpl() {
056 xstream = new XStream(new ProxyAwareJavaReflectionProvider());
057
058 // See http://xstream.codehaus.org/faq.html#Serialization_CGLIB
059 // To use a newer version of XStream we may need to do something like this:
060 // xstream = new XStream() {
061 //
062 // @Override
063 // public ReflectionProvider getReflectionProvider() {
064 // return new ProxyAwareJavaReflectionProvider();
065 // }
066 //
067 // protected MapperWrapper wrapMapper(MapperWrapper next) {
068 // return new CGLIBMapper(next);
069 // }
070 // };
071 // xstream.registerConverter(new CGLIBEnhancedConverter(xstream.getMapper(), xstream.getReflectionProvider()));
072
073 xstream.registerConverter(new ProxyConverter(xstream.getMapper(), xstream.getReflectionProvider() ));
074 xstream.addDefaultImplementation(ArrayList.class, ListProxyDefaultImpl.class);
075 xstream.registerConverter(new DateTimeConverter());
076 }
077
078 /**
079 * @see org.kuali.rice.krad.service.XmlObjectSerializer#toXml(java.lang.Object)
080 */
081 public String toXml(Object object) {
082 if ( LOG.isDebugEnabled() ) {
083 LOG.debug( "toXml(" + object + ") : \n" + xstream.toXML(object) );
084 }
085 return xstream.toXML(object);
086 }
087
088 /**
089 * @see org.kuali.rice.krad.service.XmlObjectSerializer#fromXml(java.lang.String)
090 */
091 public Object fromXml(String xml) {
092 if ( LOG.isDebugEnabled() ) {
093 LOG.debug( "fromXml() : \n" + xml );
094 }
095 if ( xml != null ) {
096 xml = xml.replaceAll( "--EnhancerByCGLIB--[0-9a-f]{0,8}", "" );
097 }
098 return xstream.fromXML(xml);
099 }
100
101 /**
102 * This custom converter only handles proxies for BusinessObjects. List-type proxies are handled by configuring XStream to treat
103 * ListProxyDefaultImpl as ArrayLists (see constructor for this service).
104 */
105 public class ProxyConverter extends ReflectionConverter {
106 public ProxyConverter(Mapper mapper, ReflectionProvider reflectionProvider) {
107 super(mapper, reflectionProvider);
108 }
109
110 @Override
111 // since the ReflectionConverter supertype defines canConvert without using a parameterized Class type, we must declare
112 // the overridden version the same way
113 @SuppressWarnings("unchecked")
114 public boolean canConvert(Class clazz) {
115 return clazz.getName().contains("CGLIB");
116 }
117
118 @Override
119 public void marshal(Object obj, HierarchicalStreamWriter writer, MarshallingContext context) {
120 super.marshal(getPersistenceService().resolveProxy(obj), writer, context);
121 }
122
123 // we shouldn't need an unmarshal method because all proxy metadata is taken out of the XML, so we'll reserialize as a base BO.
124 }
125
126 public class ProxyAwareJavaReflectionProvider extends PureJavaReflectionProvider {
127
128 public ProxyAwareJavaReflectionProvider() {
129 super();
130 }
131 /**
132 * @see com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider#visitSerializableFields(java.lang.Object, com.thoughtworks.xstream.converters.reflection.ReflectionProvider.Visitor)
133 */
134 @Override
135 public void visitSerializableFields(Object object, Visitor visitor) {
136 for (Iterator iterator = fieldDictionary.serializableFieldsFor(object.getClass()); iterator.hasNext();) {
137 Field field = (Field) iterator.next();
138 if (!fieldModifiersSupported(field)) {
139 continue;
140 }
141 validateFieldAccess(field);
142 Object value = null;
143 try {
144 value = field.get(object);
145 if (value != null && getPersistenceService().isProxied(value)) {
146 value = getPersistenceService().resolveProxy(value);
147 }
148 } catch (IllegalArgumentException e) {
149 throw new ObjectAccessException("Could not get field " + field.getClass() + "." + field.getName(), e);
150 } catch (IllegalAccessException e) {
151 throw new ObjectAccessException("Could not get field " + field.getClass() + "." + field.getName(), e);
152 }
153 visitor.visit(field.getName(), field.getType(), field.getDeclaringClass(), value);
154 }
155 }
156
157 }
158
159 public PersistenceService getPersistenceService() {
160 if ( persistenceService == null ) {
161 persistenceService = KRADServiceLocator.getPersistenceService();
162 }
163 return persistenceService;
164 }
165
166 }