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/* * Copyright 2002-2014 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.orm.jpa.vendor; import java.lang.reflect.Method; import java.sql.Connection; import java.sql.SQLException; import javax.persistence.EntityManager; import javax.persistence.PersistenceException; import org.hibernate.FlushMode; import org.hibernate.HibernateException; import org.hibernate.NonUniqueObjectException; import org.hibernate.NonUniqueResultException; import org.hibernate.ObjectDeletedException; import org.hibernate.OptimisticLockException; import org.hibernate.PersistentObjectException; import org.hibernate.PessimisticLockException; import org.hibernate.PropertyValueException; import org.hibernate.QueryException; import org.hibernate.QueryTimeoutException; import org.hibernate.Session; import org.hibernate.StaleObjectStateException; import org.hibernate.StaleStateException; import org.hibernate.TransientObjectException; import org.hibernate.UnresolvableObjectException; import org.hibernate.WrongClassException; import org.hibernate.exception.ConstraintViolationException; import org.hibernate.exception.DataException; import org.hibernate.exception.JDBCConnectionException; import org.hibernate.exception.LockAcquisitionException; import org.hibernate.exception.SQLGrammarException; import org.springframework.dao.CannotAcquireLockException; import org.springframework.dao.DataAccessException; import org.springframework.dao.DataAccessResourceFailureException; import org.springframework.dao.DataIntegrityViolationException; import org.springframework.dao.DuplicateKeyException; import org.springframework.dao.IncorrectResultSizeDataAccessException; import org.springframework.dao.InvalidDataAccessApiUsageException; import org.springframework.dao.InvalidDataAccessResourceUsageException; import org.springframework.dao.PessimisticLockingFailureException; import org.springframework.jdbc.datasource.ConnectionHandle; import org.springframework.jdbc.datasource.DataSourceUtils; import org.springframework.jdbc.support.JdbcUtils; import org.springframework.orm.ObjectOptimisticLockingFailureException; import org.springframework.orm.ObjectRetrievalFailureException; import org.springframework.orm.jpa.DefaultJpaDialect; import org.springframework.orm.jpa.EntityManagerFactoryUtils; import org.springframework.orm.jpa.JpaSystemException; import org.springframework.transaction.InvalidIsolationLevelException; import org.springframework.transaction.TransactionDefinition; import org.springframework.transaction.TransactionException; import org.springframework.util.ClassUtils; import org.springframework.util.ReflectionUtils; /** * {@link org.springframework.orm.jpa.JpaDialect} implementation for * Hibernate EntityManager. Developed against Hibernate 3.6 and 4.2/4.3. * * @author Juergen Hoeller * @author Costin Leau * @since 2.0 */ @SuppressWarnings({ "serial", "deprecation" }) public class HibernateJpaDialect extends DefaultJpaDialect { private static Class<?> optimisticLockExceptionClass; private static Class<?> pessimisticLockExceptionClass; static { // Checking for Hibernate 4.x's Optimistic/PessimisticEntityLockException ClassLoader cl = HibernateJpaDialect.class.getClassLoader(); try { optimisticLockExceptionClass = cl.loadClass("org.hibernate.dialect.lock.OptimisticEntityLockException"); } catch (ClassNotFoundException ex) { // OptimisticLockException is deprecated on Hibernate 4.x; we're just using it on 3.x anyway optimisticLockExceptionClass = OptimisticLockException.class; } try { pessimisticLockExceptionClass = cl .loadClass("org.hibernate.dialect.lock.PessimisticEntityLockException"); } catch (ClassNotFoundException ex) { pessimisticLockExceptionClass = null; } } private boolean prepareConnection = (HibernateConnectionHandle.sessionConnectionMethod == null); /** * Set whether to prepare the underlying JDBC Connection of a transactional * Hibernate Session, that is, whether to apply a transaction-specific * isolation level and/or the transaction's read-only flag to the underlying * JDBC Connection. * <p>Default is "true" on Hibernate EntityManager 4.x (with its 'on-close' * connection release mode, and "false" on Hibernate EntityManager 3.6 (due to * the 'after-transaction' release mode there). <b>Note that Hibernate 4.2+ is * strongly recommended in order to make isolation levels work efficiently.</b> * <p>If you turn this flag off, JPA transaction management will not support * per-transaction isolation levels anymore. It will not call * {@code Connection.setReadOnly(true)} for read-only transactions anymore either. * If this flag is turned off, no cleanup of a JDBC Connection is required after * a transaction, since no Connection settings will get modified. * @see java.sql.Connection#setTransactionIsolation * @see java.sql.Connection#setReadOnly */ public void setPrepareConnection(boolean prepareConnection) { this.prepareConnection = prepareConnection; } @Override public Object beginTransaction(EntityManager entityManager, TransactionDefinition definition) throws PersistenceException, SQLException, TransactionException { Session session = getSession(entityManager); if (definition.getTimeout() != TransactionDefinition.TIMEOUT_DEFAULT) { session.getTransaction().setTimeout(definition.getTimeout()); } boolean isolationLevelNeeded = (definition.getIsolationLevel() != TransactionDefinition.ISOLATION_DEFAULT); Integer previousIsolationLevel = null; boolean resetConnection = false; if (isolationLevelNeeded || definition.isReadOnly()) { if (this.prepareConnection) { Connection con = HibernateConnectionHandle.doGetConnection(session); previousIsolationLevel = DataSourceUtils.prepareConnectionForTransaction(con, definition); resetConnection = true; } else if (isolationLevelNeeded) { throw new InvalidIsolationLevelException(getClass().getSimpleName() + " does not support custom isolation levels since the 'prepareConnection' flag is off. " + "This is the case on Hibernate 3.6 by default; either switch that flag at your own risk " + "or upgrade to Hibernate 4.x, with 4.2+ recommended."); } } // Standard JPA transaction begin call for full JPA context setup... entityManager.getTransaction().begin(); // Adapt flush mode and store previous isolation level, if any. FlushMode previousFlushMode = prepareFlushMode(session, definition.isReadOnly()); return new SessionTransactionData(session, previousFlushMode, resetConnection, previousIsolationLevel); } @Override public Object prepareTransaction(EntityManager entityManager, boolean readOnly, String name) throws PersistenceException { Session session = getSession(entityManager); FlushMode previousFlushMode = prepareFlushMode(session, readOnly); return new SessionTransactionData(session, previousFlushMode, false, null); } protected FlushMode prepareFlushMode(Session session, boolean readOnly) throws PersistenceException { FlushMode flushMode = session.getFlushMode(); if (readOnly) { // We should suppress flushing for a read-only transaction. if (!flushMode.equals(FlushMode.MANUAL)) { session.setFlushMode(FlushMode.MANUAL); return flushMode; } } else { // We need AUTO or COMMIT for a non-read-only transaction. if (flushMode.lessThan(FlushMode.COMMIT)) { session.setFlushMode(FlushMode.AUTO); return flushMode; } } // No FlushMode change needed... return null; } @Override public void cleanupTransaction(Object transactionData) { ((SessionTransactionData) transactionData).resetSessionState(); } @Override public ConnectionHandle getJdbcConnection(EntityManager entityManager, boolean readOnly) throws PersistenceException, SQLException { Session session = getSession(entityManager); return new HibernateConnectionHandle(session); } @Override public DataAccessException translateExceptionIfPossible(RuntimeException ex) { if (ex instanceof HibernateException) { return convertHibernateAccessException((HibernateException) ex); } if (ex instanceof PersistenceException && ex.getCause() instanceof HibernateException) { return convertHibernateAccessException((HibernateException) ex.getCause()); } return EntityManagerFactoryUtils.convertJpaAccessExceptionIfPossible(ex); } /** * Convert the given HibernateException to an appropriate exception * from the {@code org.springframework.dao} hierarchy. * @param ex HibernateException that occurred * @return the corresponding DataAccessException instance */ protected DataAccessException convertHibernateAccessException(HibernateException ex) { if (ex instanceof JDBCConnectionException) { return new DataAccessResourceFailureException(ex.getMessage(), ex); } if (ex instanceof SQLGrammarException) { SQLGrammarException jdbcEx = (SQLGrammarException) ex; return new InvalidDataAccessResourceUsageException(ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]", ex); } if (ex instanceof QueryTimeoutException) { QueryTimeoutException jdbcEx = (QueryTimeoutException) ex; return new org.springframework.dao.QueryTimeoutException( ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]", ex); } if (ex instanceof LockAcquisitionException) { LockAcquisitionException jdbcEx = (LockAcquisitionException) ex; return new CannotAcquireLockException(ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]", ex); } if (ex instanceof PessimisticLockException) { PessimisticLockException jdbcEx = (PessimisticLockException) ex; return new PessimisticLockingFailureException(ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]", ex); } if (ex instanceof ConstraintViolationException) { ConstraintViolationException jdbcEx = (ConstraintViolationException) ex; return new DataIntegrityViolationException(ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]; constraint [" + jdbcEx.getConstraintName() + "]", ex); } if (ex instanceof DataException) { DataException jdbcEx = (DataException) ex; return new DataIntegrityViolationException(ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]", ex); } // end of JDBCException subclass handling if (ex instanceof QueryException) { return new InvalidDataAccessResourceUsageException(ex.getMessage(), ex); } if (ex instanceof NonUniqueResultException) { return new IncorrectResultSizeDataAccessException(ex.getMessage(), 1, ex); } if (ex instanceof NonUniqueObjectException) { return new DuplicateKeyException(ex.getMessage(), ex); } if (ex instanceof PropertyValueException) { return new DataIntegrityViolationException(ex.getMessage(), ex); } if (ex instanceof PersistentObjectException) { return new InvalidDataAccessApiUsageException(ex.getMessage(), ex); } if (ex instanceof TransientObjectException) { return new InvalidDataAccessApiUsageException(ex.getMessage(), ex); } if (ex instanceof ObjectDeletedException) { return new InvalidDataAccessApiUsageException(ex.getMessage(), ex); } if (ex instanceof UnresolvableObjectException) { UnresolvableObjectException hibEx = (UnresolvableObjectException) ex; return new ObjectRetrievalFailureException(hibEx.getEntityName(), hibEx.getIdentifier(), ex.getMessage(), ex); } if (ex instanceof WrongClassException) { WrongClassException hibEx = (WrongClassException) ex; return new ObjectRetrievalFailureException(hibEx.getEntityName(), hibEx.getIdentifier(), ex.getMessage(), ex); } if (ex instanceof StaleObjectStateException) { StaleObjectStateException hibEx = (StaleObjectStateException) ex; return new ObjectOptimisticLockingFailureException(hibEx.getEntityName(), hibEx.getIdentifier(), ex); } if (ex instanceof StaleStateException) { return new ObjectOptimisticLockingFailureException(ex.getMessage(), ex); } if (optimisticLockExceptionClass.isInstance(ex)) { return new ObjectOptimisticLockingFailureException(ex.getMessage(), ex); } if (pessimisticLockExceptionClass != null && pessimisticLockExceptionClass.isInstance(ex)) { if (ex.getCause() instanceof LockAcquisitionException) { return new CannotAcquireLockException(ex.getMessage(), ex.getCause()); } return new PessimisticLockingFailureException(ex.getMessage(), ex); } // fallback return new JpaSystemException(ex); } protected Session getSession(EntityManager entityManager) { return entityManager.unwrap(Session.class); } private static class SessionTransactionData { private final Session session; private final FlushMode previousFlushMode; private final boolean resetConnection; private final Integer previousIsolationLevel; public SessionTransactionData(Session session, FlushMode previousFlushMode, boolean resetConnection, Integer previousIsolationLevel) { this.session = session; this.previousFlushMode = previousFlushMode; this.resetConnection = resetConnection; this.previousIsolationLevel = previousIsolationLevel; } public void resetSessionState() { if (this.previousFlushMode != null) { this.session.setFlushMode(this.previousFlushMode); } if (this.resetConnection && this.session.isConnected()) { Connection con = HibernateConnectionHandle.doGetConnection(this.session); DataSourceUtils.resetConnectionAfterTransaction(con, this.previousIsolationLevel); } } } private static class HibernateConnectionHandle implements ConnectionHandle { // This will find a corresponding method on Hibernate 3.x but not on 4.x private static final Method sessionConnectionMethod = ClassUtils.getMethodIfAvailable(Session.class, "connection"); private static volatile Method connectionMethodToUse = sessionConnectionMethod; private final Session session; public HibernateConnectionHandle(Session session) { this.session = session; } @Override public Connection getConnection() { return doGetConnection(this.session); } @Override public void releaseConnection(Connection con) { if (sessionConnectionMethod != null) { // Need to explicitly call close() with Hibernate 3.x in order to allow // for eager release of the underlying physical Connection if necessary. // However, do not do this on Hibernate 4.2+ since it would return the // physical Connection to the pool right away, making it unusable for // further operations within the current transaction! JdbcUtils.closeConnection(con); } } public static Connection doGetConnection(Session session) { try { if (connectionMethodToUse == null) { // Reflective lookup to find SessionImpl's connection() method on Hibernate 4.x connectionMethodToUse = session.getClass().getMethod("connection"); } return (Connection) ReflectionUtils.invokeMethod(connectionMethodToUse, session); } catch (NoSuchMethodException ex) { throw new IllegalStateException("Cannot find connection() method on Hibernate Session", ex); } } } }