XAResourceImpl.java

/*
 * JOnAS: Java(TM) Open Application Server
 * Copyright (C) 1999 Bull S.A.
 * Contact: jonas-team@objectweb.org
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 * USA
 *
 * --------------------------------------------------------------------------
 * $Id: XAResourceImpl.java,v 1.13 2004/04/28 15:31:21 durieuxp Exp $
 * --------------------------------------------------------------------------
 */


package org.objectweb.jonas.jdbc_xa;

import java.sql.Connection;
import java.sql.SQLException;
import javax.transaction.xa.*;
import org.objectweb.jonas.common.Log;
import org.objectweb.util.monolog.api.Logger;
import org.objectweb.util.monolog.api.BasicLevel;

public class XAResourceImpl implements XAResource {

    private static Logger logger = null;

    private Connection actConn = null;
    private XAConnectionImpl xac = null;
    private int timeout;
    private Xid currXid = null;
    private boolean xaStarted = false;
    private String rmid = null;

    // -----------------------------------------------------------------
    // Constructors
    // -----------------------------------------------------------------

    public XAResourceImpl(XAConnectionImpl xac, Connection actual, XADataSourceImpl ds) {
        this.xac = xac;
        this.actConn = actual;
        this.rmid = ds.getDataSourceName();
        logger = Log.getLogger(Log.JONAS_JDBCXA_PREFIX);
        logger.log(BasicLevel.DEBUG, "new object for " + this);
    }

    // -----------------------------------------------------------------
    // XAResource implementation
    // -----------------------------------------------------------------

    public synchronized void commit(Xid xid, boolean onePhase) throws XAException {

        logger.log(BasicLevel.DEBUG, "XA-COMMIT for " + this);
        logger.log(BasicLevel.DEBUG, "Xid = " + xid);

        // Make sure that we do not mix transactions
        // Since start and end are not sent to database, we must check here
        // the xids.
        if (currXid != null && !currXid.equals(xid)) {
            logger.log(BasicLevel.DEBUG, "mixed xids: " + xid + " != " + currXid);
            XAException ex = new XAException("cannot mix transactions");
            throw(ex);
        }
        currXid = null;         // just for cleaning
        if (xaStarted) {
            // Unbalance start/end. Probably a close is missing.
            // We decide to unset xa_start here to avoid a further error, but
            // I'm not sure it's a good idea.
            logger.log(BasicLevel.WARN, "XA START without XA END");
            
            xaStarted = false;
        }

        // Commit the transaction
        try {
            actConn.commit();
        } catch (SQLException e) {
            logger.log(BasicLevel.ERROR, "Cannot commit transaction:" + e);
            xac.notifyError(e);
            throw(new XAException("Error on commit"));
        }
    }

    public synchronized void end(Xid xid, int flags) throws XAException {

        logger.log(BasicLevel.DEBUG, "XA-END for " + this);
        logger.log(BasicLevel.DEBUG, "Xid = " + xid);

        // Check that we got a start on this Xid first.
        if (currXid == null || !currXid.equals(xid)) {
            logger.log(BasicLevel.WARN, "END without START or mixed xids: " + xid + " != " + currXid);
            XAException ex = new XAException(XAException.XA_RBPROTO);
            throw(ex);
        }
        xaStarted = false;
    }

    public synchronized void forget(Xid xid) throws XAException {

        // not implemented. XXX
        logger.log(BasicLevel.DEBUG, "XA-FORGET for " + this);
        logger.log(BasicLevel.DEBUG, "Xid = " + xid);
        currXid = null;
    }

    public synchronized int getTransactionTimeout() throws XAException {
        logger.log(BasicLevel.DEBUG, "getTransactionTimeout for " + this);
        return timeout;
    }

    public boolean isSameRM(XAResource xares) throws XAException {


        // In this pseudo-driver, we must return true only if
        // both objects refer to the same XAResource, and not
        // the same Resource Manager, because actually, we must
        // send commit/rollback on each XAResource involved in
        // the transaction.
        if (xares.equals(this)) {
            logger.log(BasicLevel.DEBUG, "isSameRM = true " + this);
            return true;
        }
        logger.log(BasicLevel.DEBUG, "isSameRM = false " + this);
        return false;
    }


    public synchronized int prepare(Xid xid) throws XAException {

        logger.log(BasicLevel.DEBUG, "XA-PREPARE for " + this);
        logger.log(BasicLevel.DEBUG, "Xid = " + xid);
        // No 2PC on standard JDBC drivers
        return XA_OK;
    }

    public synchronized Xid[] recover(int flag) throws XAException {

        logger.log(BasicLevel.DEBUG, "XA-RECOVER for " + this);
        // Not implemented
        return null;
    }
    
    public synchronized void rollback(Xid xid) throws XAException {

        logger.log(BasicLevel.DEBUG, "XA-ROLLBACK for " + this);
        logger.log(BasicLevel.DEBUG, "Xid = " + xid);

        // Make sure that we do not mix transactions
        // Since start and end are not sent to database, we must check here
        // the xids.
        if (currXid != null && !currXid.equals(xid)) {
            logger.log(BasicLevel.DEBUG, "mixed xids: " + xid + " != " + currXid);
            XAException ex = new XAException("Cannot mix transactions");
            throw(ex);
        }
        currXid = null;         // just for cleaning
        if (xaStarted) {
            // Unbalance start/end. Probably a close is missing.
            // We decide to unset xa_start here to avoid a further error, but
            // I'm not sure it's a good idea.
            logger.log(BasicLevel.WARN, "XA START without XA END");
            xaStarted = false;
        }

        // Make sure that we are not in AutoCommit mode
        try {
            if (actConn.getAutoCommit() == true) {
                logger.log(BasicLevel.ERROR, "Rollback called on XAResource with AutoCommit set");
                throw (new XAException(XAException.XA_HEURCOM));
            }
        } catch (SQLException e) {
            logger.log(BasicLevel.ERROR, "Cannot getAutoCommit:" + e);
            xac.notifyError(e);
            throw(new XAException("Error on getAutoCommit"));
        }
        
        // Rollback the transaction
        try {
            actConn.rollback();
        } catch (SQLException e) {
            logger.log(BasicLevel.ERROR, "Cannot rollback transaction:" + e);
            xac.notifyError(e);
            throw(new XAException("Error on rollback"));
        }
    }

    public synchronized boolean setTransactionTimeout(int seconds) throws XAException {

        logger.log(BasicLevel.DEBUG, "setTransactionTimeout " + this);
        timeout = seconds;
        return true;
    }

    public synchronized void start(Xid xid, int flags) throws XAException {

        logger.log(BasicLevel.DEBUG, "XA-START for " + this);
        logger.log(BasicLevel.DEBUG, "Xid = " + xid);
        if (xaStarted) {
            logger.log(BasicLevel.DEBUG, "mixed xids: " + xid + " != " + currXid);
            XAException ex = new XAException("XA START: mixed transactions");
            throw ex;
        }
        currXid = xid;
        xaStarted = true;
    }

    // ---------------------------------------------------------------------
    // Other methods
    // ---------------------------------------------------------------------

    /*
     * get the RMID
     * @return the rmid.
     */
    public String getRMID() {
        return rmid;
    }
}

---