/*
* Copyright 2005 Ralf Joachim
*
* 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.castor.persist;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Iterator;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.castor.core.util.Messages;
import org.exolab.castor.jdo.ConnectionFailedException;
import org.exolab.castor.jdo.Database;
import org.exolab.castor.jdo.TransactionAbortedException;
import org.exolab.castor.persist.LockEngine;
/**
* A transaction context is required in order to perform operations
* against the database. The transaction context is mapped to {@link
* javax.transaction.Transaction} for the ODMG API and into
* {@link javax.transaction.xa.XAResource} for XA databases. The only
* way to begin a new transaction is through the creation of a new
* transaction context. All database access must be performed through
* a transaction context.
*
* @author <a href="mailto:ralf DOT joachim AT syscon DOT eu">Ralf Joachim</a>
* @version $Revision: 7951 $ $Date: 2006-04-13 10:49:49 -0600 (Thu, 13 Apr 2006) $
* @since 1.0
*/
public final class LocalTransactionContext extends AbstractTransactionContext {
/** Log instance used for outputting debug statements. */
private static final Log LOG = LogFactory.getLog(LocalTransactionContext.class);
/**
* Create a new transaction context.
*
* @param db Database instance
*/
public LocalTransactionContext(final Database db) {
super(db);
}
/**
* {@inheritDoc}
* @see org.castor.persist.AbstractTransactionContext
* #createConnection(org.exolab.castor.persist.LockEngine)
*/
protected Connection createConnection(final LockEngine engine)
throws ConnectionFailedException {
// Get a new connection from the engine. Since the engine has no
// transaction association, we must do this sort of round trip. An attempt
// to have the transaction association in the engine inflates the code size
// in other places.
try {
Connection conn = engine.getConnectionFactory().createConnection();
conn.setAutoCommit(false);
return conn;
} catch (SQLException ex) {
throw new ConnectionFailedException(Messages.format("persist.nested", ex), ex);
}
}
/**
* {@inheritDoc}
* @see org.castor.persist.AbstractTransactionContext#commitConnections()
*/
protected void commitConnections() throws TransactionAbortedException {
try {
// Go through all the connections opened in this transaction, commit and
// close them one by one.
Iterator iter = connectionsIterator();
while (iter.hasNext()) {
// Checkpoint can only be done if transaction is not running under
// transaction monitor
((Connection) iter.next()).commit();
}
} catch (SQLException ex) {
throw new TransactionAbortedException(
Messages.format("persist.nested", ex), ex);
} finally {
Iterator iter = connectionsIterator();
while (iter.hasNext()) {
try {
((Connection) iter.next()).close();
} catch (SQLException ex) {
LOG.warn("SQLException at close JDBC Connection instance.", ex);
}
}
clearConnections();
}
}
/**
* {@inheritDoc}
* @see org.castor.persist.AbstractTransactionContext#rollbackConnections()
*/
protected void rollbackConnections() {
// Go through all the connections opened in this transaction, rollback and
// close them one by one. Ignore errors.
Iterator iter = connectionsIterator();
while (iter.hasNext()) {
Connection conn = (Connection) iter.next();
try {
conn.rollback();
LOG.debug("Connection rolled back");
conn.close();
LOG.debug("Connection closed");
} catch (SQLException ex) {
LOG.warn("SQLException at rollback/close JDBC Connection instance.", ex);
}
}
clearConnections();
}
/**
* {@inheritDoc}
* @see org.castor.persist.AbstractTransactionContext#closeConnections()
*/
protected void closeConnections() throws TransactionAbortedException { }
}