ActiveMQ example source code file (XATransaction.java)

This example ActiveMQ source code file (XATransaction.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - ActiveMQ tags/keywords

connectionid, failed, failed, in_use_state, io, ioexception, ioexception, override, start_state, throwable, transaction, transaction, xa, xaexception, xaexception

The ActiveMQ XATransaction.java source code

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.apache.activemq.transaction;

import java.io.IOException;
import javax.transaction.xa.XAException;
import javax.transaction.xa.XAResource;
import org.apache.activemq.broker.TransactionBroker;
import org.apache.activemq.command.ConnectionId;
import org.apache.activemq.command.TransactionId;
import org.apache.activemq.command.XATransactionId;
import org.apache.activemq.store.TransactionStore;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * 
 */
public class XATransaction extends Transaction {

    private static final Logger LOG = LoggerFactory.getLogger(XATransaction.class);

    private final TransactionStore transactionStore;
    private final XATransactionId xid;
    private final TransactionBroker broker;
    private final ConnectionId connectionId;

    public XATransaction(TransactionStore transactionStore, XATransactionId xid, TransactionBroker broker, ConnectionId connectionId) {
        this.transactionStore = transactionStore;
        this.xid = xid;
        this.broker = broker;
        this.connectionId = connectionId;
        if (LOG.isDebugEnabled()) {
            LOG.debug("XA Transaction new/begin : " + xid);
        }
    }

    @Override
    public void commit(boolean onePhase) throws XAException, IOException {
        if (LOG.isDebugEnabled()) {
            LOG.debug("XA Transaction commit: " + xid);
        }

        switch (getState()) {
        case START_STATE:
            // 1 phase commit, no work done.
            checkForPreparedState(onePhase);
            setStateFinished();
            break;
        case IN_USE_STATE:
            // 1 phase commit, work done.
            checkForPreparedState(onePhase);
            doPrePrepare();
            setStateFinished();
            storeCommit(getTransactionId(), false, preCommitTask, postCommitTask);
            break;
        case PREPARED_STATE:
            // 2 phase commit, work done.
            // We would record commit here.
            setStateFinished();
            storeCommit(getTransactionId(), true, preCommitTask, postCommitTask);
            break;
        default:
            illegalStateTransition("commit");
        }
    }

    private void storeCommit(TransactionId txid, boolean wasPrepared, Runnable preCommit,Runnable postCommit)
            throws XAException, IOException {
        try {
            transactionStore.commit(getTransactionId(), wasPrepared, preCommitTask, postCommitTask);
            waitPostCommitDone(postCommitTask);
        } catch (XAException xae) {
            throw xae;
        } catch (Throwable t) {
            LOG.warn("Store COMMIT FAILED: ", t);
            rollback();
            XAException xae = new XAException("STORE COMMIT FAILED: Transaction rolled back.");
            xae.errorCode = XAException.XA_RBOTHER;
            xae.initCause(t);
            throw xae;
        }
    }

    private void illegalStateTransition(String callName) throws XAException {
        XAException xae = new XAException("Cannot call " + callName + " now.");
        xae.errorCode = XAException.XAER_PROTO;
        throw xae;
    }

    private void checkForPreparedState(boolean onePhase) throws XAException {
        if (!onePhase) {
            XAException xae = new XAException("Cannot do 2 phase commit if the transaction has not been prepared.");
            xae.errorCode = XAException.XAER_PROTO;
            throw xae;
        }
    }

    private void doPrePrepare() throws XAException, IOException {
        try {
            prePrepare();
        } catch (XAException e) {
            throw e;
        } catch (Throwable e) {
            LOG.warn("PRE-PREPARE FAILED: ", e);
            rollback();
            XAException xae = new XAException("PRE-PREPARE FAILED: Transaction rolled back.");
            xae.errorCode = XAException.XA_RBOTHER;
            xae.initCause(e);
            throw xae;
        }
    }

    @Override
    public void rollback() throws XAException, IOException {

        if (LOG.isDebugEnabled()) {
            LOG.debug("XA Transaction rollback: " + xid);
        }

        switch (getState()) {
        case START_STATE:
            // 1 phase rollback no work done.
            setStateFinished();
            break;
        case IN_USE_STATE:
            // 1 phase rollback work done.
            setStateFinished();
            transactionStore.rollback(getTransactionId());
            doPostRollback();
            break;
        case PREPARED_STATE:
            // 2 phase rollback work done.
            setStateFinished();
            transactionStore.rollback(getTransactionId());
            doPostRollback();
            break;
        case FINISHED_STATE:
            // failure to commit
            transactionStore.rollback(getTransactionId());
            doPostRollback();
            break;
        default:
            throw new XAException("Invalid state");
        }

    }

    private void doPostRollback() throws XAException {
        try {
            fireAfterRollback();
        } catch (Throwable e) {
            // I guess this could happen. Post commit task failed
            // to execute properly.
            LOG.warn("POST ROLLBACK FAILED: ", e);
            XAException xae = new XAException("POST ROLLBACK FAILED");
            xae.errorCode = XAException.XAER_RMERR;
            xae.initCause(e);
            throw xae;
        }
    }

    @Override
    public int prepare() throws XAException, IOException {
        if (LOG.isDebugEnabled()) {
            LOG.debug("XA Transaction prepare: " + xid);
        }

        switch (getState()) {
        case START_STATE:
            // No work done.. no commit/rollback needed.
            setStateFinished();
            return XAResource.XA_RDONLY;
        case IN_USE_STATE:
            // We would record prepare here.
            doPrePrepare();
            setState(Transaction.PREPARED_STATE);
            transactionStore.prepare(getTransactionId());
            return XAResource.XA_OK;
        default:
            illegalStateTransition("prepare");
            return XAResource.XA_RDONLY;
        }
    }

    private void setStateFinished() {
        setState(Transaction.FINISHED_STATE);
        broker.removeTransaction(xid);
    }

    public ConnectionId getConnectionId() {
        return connectionId;
    }

    @Override
    public TransactionId getTransactionId() {
        return xid;
    }
    
    @Override
    public Logger getLog() {
        return LOG;
    }
}