Java tutorial
/* * 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.openjpa.persistence; import java.lang.reflect.AnnotatedElement; import java.lang.reflect.Field; import java.lang.reflect.Member; import java.lang.reflect.Method; import java.security.AccessController; import org.apache.commons.lang.StringUtils; import org.apache.openjpa.conf.OpenJPAConfiguration; import org.apache.openjpa.lib.log.Log; import org.apache.openjpa.lib.util.J2DoPrivHelper; import org.apache.openjpa.lib.util.Localizer; import org.apache.openjpa.meta.DelegatingMetaDataFactory; import org.apache.openjpa.meta.FieldMetaData; import org.apache.openjpa.meta.MetaDataFactory; import org.apache.openjpa.meta.MetaDataRepository; import org.apache.openjpa.meta.XMLFieldMetaData; import org.apache.openjpa.meta.XMLMetaData; /** * JAXB xml annotation metadata parser. * * @author Catalina Wei * @since 1.0.0 * @nojavadoc */ public class AnnotationPersistenceXMLMetaDataParser { private static final Localizer _loc = Localizer.forPackage(AnnotationPersistenceXMLMetaDataParser.class); private final OpenJPAConfiguration _conf; private final Log _log; private MetaDataRepository _repos = null; // cache the JAXB Xml... classes if they are present so we do not // have a hard-wired dependency on JAXB here private Class xmlTypeClass = null; private Class xmlRootElementClass = null; private Class xmlAccessorTypeClass = null; private Class xmlAttributeClass = null; private Class xmlElementClass = null; private Method xmlTypeName = null; private Method xmlTypeNamespace = null; private Method xmlRootName = null; private Method xmlRootNamespace = null; private Method xmlAttributeName = null; private Method xmlAttributeNamespace = null; private Method xmlElementName = null; private Method xmlElementNamespace = null; private Method xmlAccessorValue = null; /** * Constructor; supply configuration. */ public AnnotationPersistenceXMLMetaDataParser(OpenJPAConfiguration conf) { _conf = conf; _log = conf.getLog(OpenJPAConfiguration.LOG_METADATA); try { xmlTypeClass = Class.forName("javax.xml.bind.annotation.XmlType"); xmlTypeName = xmlTypeClass.getMethod("name", null); xmlTypeNamespace = xmlTypeClass.getMethod("namespace", null); xmlRootElementClass = Class.forName("javax.xml.bind.annotation.XmlRootElement"); xmlRootName = xmlRootElementClass.getMethod("name", null); xmlRootNamespace = xmlRootElementClass.getMethod("namespace", null); xmlAccessorTypeClass = Class.forName("javax.xml.bind.annotation.XmlAccessorType"); xmlAccessorValue = xmlAccessorTypeClass.getMethod("value", null); xmlAttributeClass = Class.forName("javax.xml.bind.annotation.XmlAttribute"); xmlAttributeName = xmlAttributeClass.getMethod("name", null); xmlAttributeNamespace = xmlAttributeClass.getMethod("namespace", null); xmlElementClass = Class.forName("javax.xml.bind.annotation.XmlElement"); xmlElementName = xmlElementClass.getMethod("name", null); xmlElementNamespace = xmlElementClass.getMethod("namespace", null); } catch (Exception e) { } } /** * Configuration supplied on construction. */ public OpenJPAConfiguration getConfiguration() { return _conf; } /** * Metadata log. */ public Log getLog() { return _log; } /** * Returns the repository for this parser. If none has been set, * create a new repository and sets it. */ public MetaDataRepository getRepository() { if (_repos == null) { MetaDataRepository repos = _conf.newMetaDataRepositoryInstance(); MetaDataFactory mdf = repos.getMetaDataFactory(); if (mdf instanceof DelegatingMetaDataFactory) mdf = ((DelegatingMetaDataFactory) mdf).getInnermostDelegate(); if (mdf instanceof PersistenceMetaDataFactory) ((PersistenceMetaDataFactory) mdf).setXMLAnnotationParser(this); _repos = repos; } return _repos; } /** * Set the metadata repository for this parser. */ public void setRepository(MetaDataRepository repos) { _repos = repos; } /** * Clear caches. */ public void clear() { } /** * Parse persistence metadata for the given field metadata. This parser/class is NOT threadsafe! The caller of * this method needs to insure that the MetaData(/Mapping)Repository is locked prior to calling this method. */ public synchronized void parse(Class<?> cls) { if (_log.isTraceEnabled()) _log.trace(_loc.get("parse-class", cls.getName())); parseXMLClassAnnotations(cls); } /** * Read annotations for the current type. */ private XMLMetaData parseXMLClassAnnotations(Class<?> cls) { // check immediately whether the class has JAXB XML annotations if (cls == null || xmlTypeClass == null || !((AccessController.doPrivileged(J2DoPrivHelper.isAnnotationPresentAction(cls, xmlTypeClass))) .booleanValue() && (AccessController .doPrivileged(J2DoPrivHelper.isAnnotationPresentAction(cls, xmlRootElementClass))) .booleanValue())) return null; // find / create metadata XMLMetaData meta = getXMLMetaData(cls); return meta; } /** * Find or create xml metadata for the current type. */ private XMLMetaData getXMLMetaData(Class<?> cls) { XMLMetaData meta = getRepository().getCachedXMLMetaData(cls); if (meta == null) { // if not in cache, create metadata meta = getRepository().addXMLClassMetaData(cls); parseXmlRootElement(cls, meta); populateFromReflection(cls, meta); } return meta; } private void parseXmlRootElement(Class type, XMLMetaData meta) { try { if (type.getAnnotation(xmlRootElementClass) != null) { meta.setXmlRootElement(true); meta.setXmlname( (String) xmlRootName.invoke(type.getAnnotation(xmlRootElementClass), new Object[] {})); meta.setXmlnamespace( (String) xmlRootNamespace.invoke(type.getAnnotation(xmlRootElementClass), new Object[] {})); } else { meta.setXmlname((String) xmlTypeName.invoke(type.getAnnotation(xmlTypeClass), new Object[] {})); meta.setXmlnamespace( (String) xmlTypeNamespace.invoke(type.getAnnotation(xmlTypeClass), new Object[] {})); } } catch (Exception e) { } } private void populateFromReflection(Class cls, XMLMetaData meta) { Member[] members; Class superclass = cls.getSuperclass(); // handle inheritance at sub-element level if ((AccessController.doPrivileged(J2DoPrivHelper.isAnnotationPresentAction(superclass, xmlTypeClass))) .booleanValue()) populateFromReflection(superclass, meta); try { if (StringUtils.equals( xmlAccessorValue.invoke(cls.getAnnotation(xmlAccessorTypeClass), new Object[] {}).toString(), "FIELD")) members = cls.getDeclaredFields(); else members = cls.getDeclaredMethods(); for (int i = 0; i < members.length; i++) { Member member = members[i]; AnnotatedElement el = (AnnotatedElement) member; XMLMetaData field = null; if (el.getAnnotation(xmlElementClass) != null) { String xmlname = (String) xmlElementName.invoke(el.getAnnotation(xmlElementClass), new Object[] {}); // avoid JAXB XML bind default name if (StringUtils.equals(XMLMetaData.defaultName, xmlname)) xmlname = member.getName(); if ((AccessController.doPrivileged( J2DoPrivHelper.isAnnotationPresentAction(((Field) member).getType(), xmlTypeClass))) .booleanValue()) { field = _repos.addXMLClassMetaData(((Field) member).getType()); parseXmlRootElement(((Field) member).getType(), field); populateFromReflection(((Field) member).getType(), field); field.setXmltype(XMLMetaData.XMLTYPE); field.setXmlname(xmlname); } else { field = _repos.newXMLFieldMetaData(((Field) member).getType(), member.getName()); field.setXmltype(XMLMetaData.ELEMENT); field.setXmlname(xmlname); field.setXmlnamespace((String) xmlElementNamespace.invoke(el.getAnnotation(xmlElementClass), new Object[] {})); } } else if (el.getAnnotation(xmlAttributeClass) != null) { field = _repos.newXMLFieldMetaData(((Field) member).getType(), member.getName()); field.setXmltype(XMLFieldMetaData.ATTRIBUTE); String xmlname = (String) xmlAttributeName.invoke(el.getAnnotation(xmlAttributeClass), new Object[] {}); // avoid JAXB XML bind default name if (StringUtils.equals(XMLMetaData.defaultName, xmlname)) xmlname = member.getName(); field.setXmlname("@" + xmlname); field.setXmlnamespace((String) xmlAttributeNamespace.invoke(el.getAnnotation(xmlAttributeClass), new Object[] {})); } if (field != null) meta.addField(member.getName(), field); } } catch (Exception e) { } } }