/*
* Copyright 2002-2016 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;
import java.io.Serializable;
import java.sql.SQLException;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceException;
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.datasource.ConnectionHandle;
import org.springframework.transaction.InvalidIsolationLevelException;
import org.springframework.transaction.TransactionDefinition;
import org.springframework.transaction.TransactionException;
/**
* Default implementation of the {@link JpaDialect} interface.
* Used as default dialect by {@link JpaTransactionManager}.
*
* <p>Simply begins a standard JPA transaction in {@link #beginTransaction} and
* performs standard exception translation through {@link EntityManagerFactoryUtils}.
*
* <p><b>NOTE: Spring's JPA support requires JPA 2.1 or higher, as of Spring 5.0.</b>
*
* @author Juergen Hoeller
* @since 2.0
* @see JpaTransactionManager#setJpaDialect
*/
@SuppressWarnings("serial")
public class DefaultJpaDialect implements JpaDialect, Serializable {
/**
* This implementation invokes the standard JPA {@code Transaction.begin}
* method. Throws an InvalidIsolationLevelException if a non-default isolation
* level is set.
* <p>This implementation does not return any transaction data Object, since there
* is no state to be kept for a standard JPA transaction. Hence, subclasses do not
* have to care about the return value ({@code null}) of this implementation
* and are free to return their own transaction data Object.
* @see javax.persistence.EntityTransaction#begin
* @see org.springframework.transaction.InvalidIsolationLevelException
* @see #cleanupTransaction
*/
@Override
public Object beginTransaction(EntityManager entityManager, TransactionDefinition definition)
throws PersistenceException, SQLException, TransactionException {
if (definition.getIsolationLevel() != TransactionDefinition.ISOLATION_DEFAULT) {
throw new InvalidIsolationLevelException(getClass().getSimpleName() +
" does not support custom isolation levels due to limitations in standard JPA. " +
"Specific arrangements may be implemented in custom JpaDialect variants.");
}
entityManager.getTransaction().begin();
return null;
}
@Override
public Object prepareTransaction(EntityManager entityManager, boolean readOnly, String name)
throws PersistenceException {
return null;
}
/**
* This implementation does nothing, since the default {@code beginTransaction}
* implementation does not require any cleanup.
* @see #beginTransaction
*/
@Override
public void cleanupTransaction(Object transactionData) {
}
/**
* This implementation always returns {@code null},
* indicating that no JDBC Connection can be provided.
*/
@Override
public ConnectionHandle getJdbcConnection(EntityManager entityManager, boolean readOnly)
throws PersistenceException, SQLException {
return null;
}
/**
* This implementation does nothing, assuming that the Connection
* will implicitly be closed with the EntityManager.
* <p>If the JPA implementation returns a Connection handle that it expects
* the application to close after use, the dialect implementation needs to invoke
* {@code Connection.close()} (or some other method with similar effect) here.
* @see java.sql.Connection#close()
*/
@Override
public void releaseJdbcConnection(ConnectionHandle conHandle, EntityManager em)
throws PersistenceException, SQLException {
}
//-----------------------------------------------------------------------------------
// Hook for exception translation (used by JpaTransactionManager)
//-----------------------------------------------------------------------------------
/**
* This implementation delegates to EntityManagerFactoryUtils.
* @see EntityManagerFactoryUtils#convertJpaAccessExceptionIfPossible
*/
@Override
public DataAccessException translateExceptionIfPossible(RuntimeException ex) {
return EntityManagerFactoryUtils.convertJpaAccessExceptionIfPossible(ex);
}
}