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/* * Copyright 2011 the original author or authors. * * Licensed 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.springframework.data.mongodb.crossstore; import javax.persistence.EntityManagerFactory; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.dao.DataAccessException; import org.springframework.dao.DataAccessResourceFailureException; import org.springframework.dao.DataIntegrityViolationException; import org.springframework.data.crossstore.ChangeSet; import org.springframework.data.crossstore.ChangeSetBacked; import org.springframework.data.crossstore.ChangeSetPersister; import org.springframework.data.mongodb.core.CollectionCallback; import org.springframework.data.mongodb.core.MongoTemplate; import org.springframework.util.ClassUtils; import com.mongodb.BasicDBObject; import com.mongodb.DBCollection; import com.mongodb.DBObject; import com.mongodb.MongoException; public class MongoChangeSetPersister implements ChangeSetPersister<Object> { private static final String ENTITY_CLASS = "_entity_class"; private static final String ENTITY_ID = "_entity_id"; private static final String ENTITY_FIELD_NAME = "_entity_field_name"; private static final String ENTITY_FIELD_CLASS = "_entity_field_class"; protected final Log log = LogFactory.getLog(getClass()); private MongoTemplate mongoTemplate; private EntityManagerFactory entityManagerFactory; public void setMongoTemplate(MongoTemplate mongoTemplate) { this.mongoTemplate = mongoTemplate; } public void setEntityManagerFactory(EntityManagerFactory entityManagerFactory) { this.entityManagerFactory = entityManagerFactory; } public void getPersistentState(Class<? extends ChangeSetBacked> entityClass, Object id, final ChangeSet changeSet) throws DataAccessException, NotFoundException { if (id == null) { log.debug("Unable to load MongoDB data for null id"); return; } String collName = getCollectionNameForEntity(entityClass); final DBObject dbk = new BasicDBObject(); dbk.put(ENTITY_ID, id); dbk.put(ENTITY_CLASS, entityClass.getName()); if (log.isDebugEnabled()) { log.debug("Loading MongoDB data for " + dbk); } mongoTemplate.execute(collName, new CollectionCallback<Object>() { public Object doInCollection(DBCollection collection) throws MongoException, DataAccessException { for (DBObject dbo : collection.find(dbk)) { String key = (String) dbo.get(ENTITY_FIELD_NAME); if (log.isDebugEnabled()) { log.debug("Processing key: " + key); } if (!changeSet.getValues().containsKey(key)) { String className = (String) dbo.get(ENTITY_FIELD_CLASS); if (className == null) { throw new DataIntegrityViolationException("Unble to convert property " + key + ": Invalid metadata, " + ENTITY_FIELD_CLASS + " not available"); } Class<?> clazz = ClassUtils.resolveClassName(className, ClassUtils.getDefaultClassLoader()); Object value = mongoTemplate.getConverter().read(clazz, dbo); if (log.isDebugEnabled()) { log.debug("Adding to ChangeSet: " + key); } changeSet.set(key, value); } } return null; } }); } public Object getPersistentId(ChangeSetBacked entity, ChangeSet cs) throws DataAccessException { log.debug("getPersistentId called on " + entity); if (entityManagerFactory == null) { throw new DataAccessResourceFailureException("EntityManagerFactory cannot be null"); } Object o = entityManagerFactory.getPersistenceUnitUtil().getIdentifier(entity); return o; } public Object persistState(ChangeSetBacked entity, ChangeSet cs) throws DataAccessException { if (cs == null) { log.debug("Flush: changeset was null, nothing to flush."); return 0L; } if (log.isDebugEnabled()) { log.debug("Flush: changeset: " + cs.getValues()); } String collName = getCollectionNameForEntity(entity.getClass()); if (mongoTemplate.getCollection(collName) == null) { mongoTemplate.createCollection(collName); } for (String key : cs.getValues().keySet()) { if (key != null && !key.startsWith("_") && !key.equals(ChangeSetPersister.ID_KEY)) { Object value = cs.getValues().get(key); final DBObject dbQuery = new BasicDBObject(); dbQuery.put(ENTITY_ID, getPersistentId(entity, cs)); dbQuery.put(ENTITY_CLASS, entity.getClass().getName()); dbQuery.put(ENTITY_FIELD_NAME, key); DBObject dbId = mongoTemplate.execute(collName, new CollectionCallback<DBObject>() { public DBObject doInCollection(DBCollection collection) throws MongoException, DataAccessException { return collection.findOne(dbQuery); } }); if (value == null) { if (log.isDebugEnabled()) { log.debug("Flush: removing: " + dbQuery); } mongoTemplate.execute(collName, new CollectionCallback<Object>() { public Object doInCollection(DBCollection collection) throws MongoException, DataAccessException { collection.remove(dbQuery); return null; } }); } else { final DBObject dbDoc = new BasicDBObject(); dbDoc.putAll(dbQuery); if (log.isDebugEnabled()) { log.debug("Flush: saving: " + dbQuery); } mongoTemplate.getConverter().write(value, dbDoc); dbDoc.put(ENTITY_FIELD_CLASS, value.getClass().getName()); if (dbId != null) { dbDoc.put("_id", dbId.get("_id")); } mongoTemplate.execute(collName, new CollectionCallback<Object>() { public Object doInCollection(DBCollection collection) throws MongoException, DataAccessException { collection.save(dbDoc); return null; } }); } } } return 0L; } private String getCollectionNameForEntity(Class<? extends ChangeSetBacked> entityClass) { return ClassUtils.getQualifiedName(entityClass); } }