001 /*
002 GRANITE DATA SERVICES
003 Copyright (C) 2011 GRANITE DATA SERVICES S.A.S.
004
005 This file is part of Granite Data Services.
006
007 Granite Data Services is free software; you can redistribute it and/or modify
008 it under the terms of the GNU Library General Public License as published by
009 the Free Software Foundation; either version 2 of the License, or (at your
010 option) any later version.
011
012 Granite Data Services is distributed in the hope that it will be useful, but
013 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
014 FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
015 for more details.
016
017 You should have received a copy of the GNU Library General Public License
018 along with this library; if not, see <http://www.gnu.org/licenses/>.
019 */
020
021 package org.granite.hibernate4;
022
023 import java.io.Serializable;
024 import java.lang.reflect.Field;
025 import java.lang.reflect.Method;
026 import java.lang.reflect.Type;
027 import java.util.concurrent.ConcurrentHashMap;
028
029 import javax.persistence.EmbeddedId;
030 import javax.persistence.Id;
031
032 import org.granite.config.GraniteConfig;
033 import org.granite.context.GraniteContext;
034 import org.granite.messaging.service.ServiceException;
035 import org.granite.util.TypeUtil;
036 import org.granite.util.Introspector;
037 import org.granite.util.PropertyDescriptor;
038 import org.hibernate.engine.spi.SessionImplementor;
039 import org.hibernate.proxy.HibernateProxy;
040 import org.hibernate.type.CompositeType;
041
042 /**
043 * @author Franck WOLFF
044 */
045 public class ProxyFactory {
046
047 private static final Class<?>[] INTERFACES = new Class<?>[]{HibernateProxy.class};
048 private static final Class<?>[] SINGLE_OBJECT_PARAMS = new Class<?>[]{Object.class};
049 private static final Method OBJECT_EQUALS;
050 static {
051 try {
052 OBJECT_EQUALS = Object.class.getMethod("equals", SINGLE_OBJECT_PARAMS);
053 }
054 catch (Exception e) {
055 throw new ExceptionInInitializerError(e);
056 }
057 }
058
059 protected final ConcurrentHashMap<Class<?>, Object[]> identifierInfos = new ConcurrentHashMap<Class<?>, Object[]>();
060
061 private final Method getProxyFactory;
062 private final Method getProxy;
063 private final boolean classOverridesEqualsParameter;
064
065 public ProxyFactory(String initializerClassName) {
066 try {
067 // Get proxy methods: even if CGLIB/Javassist LazyInitializer implementations share a common
068 // superclass, getProxyFactory/getProxy methods are declared as static in each inherited
069 // class with the same signature.
070 Class<?> initializerClass = TypeUtil.forName(initializerClassName);
071 getProxyFactory = initializerClass.getMethod("getProxyFactory", new Class[] { Class.class, Class[].class });
072
073 // Hibernate 4.0.1 has an extra boolean parameter in last position: classOverridesEquals.
074 Method getProxy = null;
075 boolean classOverridesEqualsParameter = false;
076 try {
077 getProxy = initializerClass.getMethod("getProxy", new Class[]{
078 Class.class, String.class, Class.class, Class[].class, Method.class, Method.class,
079 CompositeType.class, Serializable.class, SessionImplementor.class
080 });
081 }
082 catch (NoSuchMethodException e) {
083 getProxy = initializerClass.getMethod("getProxy", new Class[]{
084 Class.class, String.class, Class.class, Class[].class, Method.class, Method.class,
085 CompositeType.class, Serializable.class, SessionImplementor.class, Boolean.TYPE
086 });
087 classOverridesEqualsParameter = true;
088 }
089 this.getProxy = getProxy;
090 this.classOverridesEqualsParameter = classOverridesEqualsParameter;
091 }
092 catch (Exception e) {
093 throw new ServiceException("Could not introspect initializer class: " + initializerClassName, e);
094 }
095 }
096
097 public HibernateProxy getProxyInstance(String persistentClassName, String entityName, Serializable id) {
098 try {
099 // Get ProxyFactory.
100 Class<?> persistentClass = TypeUtil.forName(persistentClassName);
101 Class<?> factory = (Class<?>)getProxyFactory.invoke(null, new Object[] { persistentClass, INTERFACES });
102
103 // Convert id (if necessary).
104 Object[] identifierInfo = getIdentifierInfo(persistentClass);
105 Type identifierType = (Type)identifierInfo[0];
106 Method identifierGetter = (Method)identifierInfo[1];
107 if (id == null || !identifierType.equals(id.getClass())) {
108 GraniteConfig config = GraniteContext.getCurrentInstance().getGraniteConfig();
109 id = (Serializable)config.getConverters().convert(id, identifierType);
110 }
111
112 // Get Proxy (with or without the extra parameter classOverridesEquals)
113 if (classOverridesEqualsParameter) {
114 return (HibernateProxy)getProxy.invoke(null, new Object[]{
115 factory, entityName, persistentClass, INTERFACES, identifierGetter, null, null, id, null, overridesEquals(persistentClass)});
116 }
117 return (HibernateProxy)getProxy.invoke(null, new Object[] { factory, entityName, persistentClass, INTERFACES, identifierGetter, null, null, id, null });
118 }
119 catch (Exception e) {
120 throw new ServiceException("Error with proxy description: " + persistentClassName + '/' + entityName + " and id: " + id, e);
121 }
122 }
123
124 protected boolean overridesEquals(Class<?> persistentClass) {
125 try {
126 return !OBJECT_EQUALS.equals(persistentClass.getMethod("equals", SINGLE_OBJECT_PARAMS));
127 }
128 catch (Exception e) {
129 return false; // should never happen unless persistentClass is an interface...
130 }
131 }
132
133 protected Object[] getIdentifierInfo(Class<?> persistentClass) {
134
135 Object[] info = identifierInfos.get(persistentClass);
136 if (info != null)
137 return info;
138
139 Type type = null;
140 Method getter = null;
141 for (Class<?> clazz = persistentClass; clazz != Object.class && clazz != null; clazz = clazz.getSuperclass()) {
142 for (Field field : clazz.getDeclaredFields()) {
143 if (field.isAnnotationPresent(Id.class) || field.isAnnotationPresent(EmbeddedId.class)) {
144 type = field.getGenericType();
145 break;
146 }
147 }
148 }
149
150 if (type == null) {
151 PropertyDescriptor[] propertyDescriptors = Introspector.getPropertyDescriptors(persistentClass);
152
153 for (PropertyDescriptor propertyDescriptor : propertyDescriptors) {
154 Method method = propertyDescriptor.getReadMethod();
155 if (method != null && (
156 method.isAnnotationPresent(Id.class) ||
157 method.isAnnotationPresent(EmbeddedId.class))) {
158 type = method.getGenericReturnType();
159 getter = method;
160 break;
161 }
162 method = propertyDescriptor.getWriteMethod();
163 if (method != null && (
164 method.isAnnotationPresent(Id.class) ||
165 method.isAnnotationPresent(EmbeddedId.class))) {
166 type = method.getGenericParameterTypes()[0];
167 break;
168 }
169 }
170 }
171
172 if (type != null) {
173 info = new Object[] { type, getter };
174 Object[] previousInfo = identifierInfos.putIfAbsent(persistentClass, info);
175 if (previousInfo != null)
176 info = previousInfo; // should be the same...
177 return info;
178 }
179
180 throw new IllegalArgumentException("Could not find id in: " + persistentClass);
181 }
182 }