/*
* $Id: SelectSqlStatementStrategy.java 19201 2010-08-26 03:07:16Z dirk.olmes $
* --------------------------------------------------------------------------------------
* Copyright (c) MuleSoft, Inc. All rights reserved. http://www.mulesoft.com
*
* The software in this package is published under the terms of the CPAL v1.0
* license, a copy of which has been included with this distribution in the
* LICENSE.txt file.
*/
package org.mule.transport.jdbc.sqlstrategy;
import org.mule.DefaultMuleMessage;
import org.mule.api.MuleEvent;
import org.mule.api.MuleMessage;
import org.mule.api.endpoint.ImmutableEndpoint;
import org.mule.api.transaction.Transaction;
import org.mule.transaction.TransactionCoordination;
import org.mule.transport.jdbc.JdbcConnector;
import org.mule.transport.jdbc.JdbcUtils;
import org.mule.util.ArrayUtils;
import java.sql.Connection;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import org.apache.log4j.Logger;
/**
* Implements strategy for handling normal select statements + acks.
*/
public class SelectSqlStatementStrategy implements SqlStatementStrategy
{
protected transient Logger logger = Logger.getLogger(getClass());
public MuleMessage executeStatement(JdbcConnector connector, ImmutableEndpoint endpoint,
MuleEvent event, long timeout) throws Exception
{
logger.debug("Trying to receive a message with a timeout of " + timeout);
String[] stmts = connector.getReadAndAckStatements(endpoint);
//Unparsed SQL statements (with #[foo] parameters)
String readStmt = stmts[0];
String ackStmt = stmts[1];
//Storage for params (format is #[foo])
List readParams = new ArrayList();
List ackParams = new ArrayList();
//Prepared statement form (with ? placeholders instead of #[foo] params)
readStmt = connector.parseStatement(readStmt, readParams);
ackStmt = connector.parseStatement(ackStmt, ackParams);
Connection con = null;
long t0 = System.currentTimeMillis();
Transaction tx = TransactionCoordination.getInstance().getTransaction();
try
{
con = connector.getConnection();
//This method is used in both JDBCMessageDispatcher and JDBCMessageRequester.
//JDBCMessageRequester specifies a finite timeout.
if (timeout < 0)
{
timeout = Long.MAX_VALUE;
}
Object result;
//do-while loop. execute query until there's a result or timeout exceeded
do
{
//Get the actual param values from the message.
Object[] params = connector.getParams(endpoint, readParams,
event != null ? event.getMessage() : null,
endpoint.getEndpointURI().getAddress());
if (logger.isDebugEnabled())
{
logger.debug("SQL QUERY: " + readStmt + ", params = " + ArrayUtils.toString(params));
}
//Perform actual query
result = connector.getQueryRunnerFor(endpoint).query(con, readStmt,
connector.getResultSetHandler(), params);
if (result != null)
{
if (logger.isDebugEnabled())
{
logger.debug("SQL query received a result: " + result);
}
else if (logger.isInfoEnabled())
{
logger.info("SQL query received a result");
}
break;
}
long sleep = Math.min(connector.getPollingFrequency(),
timeout - (System.currentTimeMillis() - t0));
if (sleep > 0)
{
if (logger.isDebugEnabled())
{
logger.debug("No results, sleeping for " + sleep);
}
Thread.sleep(sleep);
}
else
{
logger.debug("Timeout");
JdbcUtils.rollbackAndClose(con);
return null;
}
} while (true);
//Execute ack statement
if (ackStmt != null)
{
Object[] params = connector.getParams(endpoint, ackParams,
new DefaultMuleMessage(result, (Map)null, connector.getMuleContext()), ackStmt);
if (logger.isDebugEnabled())
{
logger.debug("SQL UPDATE: " + ackStmt + ", params = " + ArrayUtils.toString(params));
}
int nbRows = connector.getQueryRunnerFor(endpoint).update(con, ackStmt, params);
if (nbRows != 1)
{
logger.warn("Row count for ack should be 1 and not " + nbRows);
}
}
// Package up result
MuleMessage message = null;
if (event != null)
{
message = new DefaultMuleMessage(result, event.getMessage(), connector.getMuleContext());
}
else
{
message = new DefaultMuleMessage(result, connector.getMuleContext());
}
//Close or return connection if not in a transaction
if (tx == null)
{
JdbcUtils.commitAndClose(con);
}
return message;
}
catch (Exception e)
{
if (tx == null)
{
JdbcUtils.rollbackAndClose(con);
}
throw e;
}
}
}