/*
* Copyright 2002-2011 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.orm.jdo;
import java.lang.reflect.Method;
import java.sql.Connection;
import java.sql.SQLException;
import javax.jdo.JDOException;
import javax.jdo.PersistenceManager;
import javax.jdo.Query;
import javax.jdo.Transaction;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.dao.DataAccessException;
import org.springframework.dao.support.PersistenceExceptionTranslator;
import org.springframework.jdbc.datasource.ConnectionHandle;
import org.springframework.jdbc.support.JdbcUtils;
import org.springframework.jdbc.support.SQLExceptionTranslator;
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;
/**
* Default implementation of the {@link JdoDialect} interface.
* Updated to build on JDO 2.0 or higher, as of Spring 2.5.
* Used as default dialect by {@link JdoAccessor} and {@link JdoTransactionManager}.
*
* <p>Simply begins a standard JDO transaction in <code>beginTransaction</code>.
* Returns a handle for a JDO2 DataStoreConnection on <code>getJdbcConnection</code>.
* Calls the corresponding JDO2 PersistenceManager operation on <code>flush</code>
* Ignores a given query timeout in <code>applyQueryTimeout</code>.
* Uses a Spring SQLExceptionTranslator for exception translation, if applicable.
*
* <p>Note that, even with JDO2, vendor-specific subclasses are still necessary
* for special transaction semantics and more sophisticated exception translation.
* Furthermore, vendor-specific subclasses are encouraged to expose the native JDBC
* Connection on <code>getJdbcConnection</code>, rather than JDO2's wrapper handle.
*
* <p>This class also implements the PersistenceExceptionTranslator interface,
* as autodetected by Spring's PersistenceExceptionTranslationPostProcessor,
* for AOP-based translation of native exceptions to Spring DataAccessExceptions.
* Hence, the presence of a standard DefaultJdoDialect bean automatically enables
* a PersistenceExceptionTranslationPostProcessor to translate JDO exceptions.
*
* @author Juergen Hoeller
* @since 1.1
* @see #setJdbcExceptionTranslator
* @see JdoAccessor#setJdoDialect
* @see JdoTransactionManager#setJdoDialect
* @see org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor
*/
public class DefaultJdoDialect implements JdoDialect, PersistenceExceptionTranslator {
// JDO 3.0 setTimeoutMillis method available?
private static final Method setTimeoutMillisMethod =
ClassUtils.getMethodIfAvailable(Query.class, "setTimeoutMillis", Integer.class);
protected final Log logger = LogFactory.getLog(getClass());
private SQLExceptionTranslator jdbcExceptionTranslator;
/**
* Create a new DefaultJdoDialect.
*/
public DefaultJdoDialect() {
}
/**
* Create a new DefaultJdoDialect.
* @param connectionFactory the connection factory of the JDO PersistenceManagerFactory,
* which is used to initialize the default JDBC exception translator
* @see javax.jdo.PersistenceManagerFactory#getConnectionFactory()
* @see PersistenceManagerFactoryUtils#newJdbcExceptionTranslator(Object)
*/
public DefaultJdoDialect(Object connectionFactory) {
this.jdbcExceptionTranslator = PersistenceManagerFactoryUtils.newJdbcExceptionTranslator(connectionFactory);
}
/**
* Set the JDBC exception translator for this dialect.
* <p>Applied to any SQLException root cause of a JDOException, if specified.
* The default is to rely on the JDO provider's native exception translation.
* @param jdbcExceptionTranslator exception translator
* @see java.sql.SQLException
* @see javax.jdo.JDOException#getCause()
* @see org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator
* @see org.springframework.jdbc.support.SQLStateSQLExceptionTranslator
*/
public void setJdbcExceptionTranslator(SQLExceptionTranslator jdbcExceptionTranslator) {
this.jdbcExceptionTranslator = jdbcExceptionTranslator;
}
/**
* Return the JDBC exception translator for this dialect, if any.
*/
public SQLExceptionTranslator getJdbcExceptionTranslator() {
return this.jdbcExceptionTranslator;
}
//-------------------------------------------------------------------------
// Hooks for transaction management (used by JdoTransactionManager)
//-------------------------------------------------------------------------
/**
* This implementation invokes the standard JDO <code>Transaction.begin</code>
* method. Throws an InvalidIsolationLevelException if a non-default isolation
* level is set.
* @see javax.jdo.Transaction#begin
* @see org.springframework.transaction.InvalidIsolationLevelException
*/
public Object beginTransaction(Transaction transaction, TransactionDefinition definition)
throws JDOException, SQLException, TransactionException {
if (definition.getIsolationLevel() != TransactionDefinition.ISOLATION_DEFAULT) {
throw new InvalidIsolationLevelException(
"Standard JDO does not support custom isolation levels: " +
"use a special JdoDialect implementation for your JDO provider");
}
transaction.begin();
return null;
}
/**
* This implementation does nothing, as the default beginTransaction implementation
* does not require any cleanup.
* @see #beginTransaction
*/
public void cleanupTransaction(Object transactionData) {
}
/**
* This implementation returns a DataStoreConnectionHandle for JDO2,
* which will also work on JDO1 until actually accessing the JDBC Connection.
* <p>For pre-JDO2 implementations, override this method to return the
* Connection through the corresponding vendor-specific mechanism, or <code>null</code>
* if the Connection is not retrievable.
* <p><b>NOTE:</b> A JDO2 DataStoreConnection is always a wrapper,
* never the native JDBC Connection. If you need access to the native JDBC
* Connection (or the connection pool handle, to be unwrapped via a Spring
* NativeJdbcExtractor), override this method to return the native
* Connection through the corresponding vendor-specific mechanism.
* <p>A JDO2 DataStoreConnection is only "borrowed" from the PersistenceManager:
* it needs to be returned as early as possible. Effectively, JDO2 requires the
* fetched Connection to be closed before continuing PersistenceManager work.
* For this reason, the exposed ConnectionHandle eagerly releases its JDBC
* Connection at the end of each JDBC data access operation (that is, on
* <code>DataSourceUtils.releaseConnection</code>).
* @see javax.jdo.PersistenceManager#getDataStoreConnection()
* @see org.springframework.jdbc.support.nativejdbc.NativeJdbcExtractor
* @see org.springframework.jdbc.datasource.DataSourceUtils#releaseConnection
*/
public ConnectionHandle getJdbcConnection(PersistenceManager pm, boolean readOnly)
throws JDOException, SQLException {
return new DataStoreConnectionHandle(pm);
}
/**
* This implementation does nothing, assuming that the Connection
* will implicitly be closed with the PersistenceManager.
* <p>If the JDO provider returns a Connection handle that it
* expects the application to close, the dialect needs to invoke
* <code>Connection.close</code> here.
* @see java.sql.Connection#close()
*/
public void releaseJdbcConnection(ConnectionHandle conHandle, PersistenceManager pm)
throws JDOException, SQLException {
}
/**
* This implementation applies a JDO 3.0 query timeout, if available. Otherwise,
* it sets the JPA 2.0 query hints "javax.persistence.lock.timeout" and
* "javax.persistence.query.timeout", assuming that JDO providers are often
* JPA providers as well.
*/
public void applyQueryTimeout(Query query, int remainingTimeInSeconds) throws JDOException {
if (setTimeoutMillisMethod != null) {
ReflectionUtils.invokeMethod(setTimeoutMillisMethod, query, remainingTimeInSeconds);
}
else {
query.addExtension("javax.persistence.lock.timeout", remainingTimeInSeconds);
query.addExtension("javax.persistence.query.timeout", remainingTimeInSeconds);
}
}
//-----------------------------------------------------------------------------------
// Hook for exception translation (used by JdoTransactionManager and JdoTemplate)
//-----------------------------------------------------------------------------------
/**
* Implementation of the PersistenceExceptionTranslator interface,
* as autodetected by Spring's PersistenceExceptionTranslationPostProcessor.
* <p>Converts the exception if it is a JDOException, using this JdoDialect.
* Else returns <code>null</code> to indicate an unknown exception.
* @see org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor
* @see #translateException
*/
public DataAccessException translateExceptionIfPossible(RuntimeException ex) {
if (ex instanceof JDOException) {
return translateException((JDOException) ex);
}
return null;
}
/**
* This implementation delegates to PersistenceManagerFactoryUtils.
* @see PersistenceManagerFactoryUtils#convertJdoAccessException
*/
public DataAccessException translateException(JDOException ex) {
if (getJdbcExceptionTranslator() != null && ex.getCause() instanceof SQLException) {
return getJdbcExceptionTranslator().translate("JDO operation: " + ex.getMessage(),
extractSqlStringFromException(ex), (SQLException) ex.getCause());
}
return PersistenceManagerFactoryUtils.convertJdoAccessException(ex);
}
/**
* Template method for extracting a SQL String from the given exception.
* <p>Default implementation always returns <code>null</code>. Can be overridden in
* subclasses to extract SQL Strings for vendor-specific exception classes.
* @param ex the JDOException, containing a SQLException
* @return the SQL String, or <code>null</code> if none found
*/
protected String extractSqlStringFromException(JDOException ex) {
return null;
}
/**
* ConnectionHandle implementation that fetches a new JDO2 DataStoreConnection
* for every <code>getConnection</code> call and closes the Connection on
* <code>releaseConnection</code>. This is necessary because JDO2 requires the
* fetched Connection to be closed before continuing PersistenceManager work.
* @see javax.jdo.PersistenceManager#getDataStoreConnection()
*/
private static class DataStoreConnectionHandle implements ConnectionHandle {
private final PersistenceManager persistenceManager;
public DataStoreConnectionHandle(PersistenceManager persistenceManager) {
this.persistenceManager = persistenceManager;
}
public Connection getConnection() {
return (Connection) this.persistenceManager.getDataStoreConnection();
}
public void releaseConnection(Connection con) {
JdbcUtils.closeConnection(con);
}
}
}