jtajobrunshell.java

来自「Quartz 是个开源的作业调度框架」· Java 代码 · 共 141 行

/* 
 * Copyright 2004-2005 OpenSymphony 
 * 
 * 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.
 * 
 */

/*
 * Previously Copyright (c) 2001-2004 James House
 */
package org.quartz.ee.jta;

import javax.transaction.Status;
import javax.transaction.SystemException;
import javax.transaction.UserTransaction;

import org.quartz.Scheduler;
import org.quartz.SchedulerException;
import org.quartz.core.JobRunShell;
import org.quartz.core.JobRunShellFactory;
import org.quartz.core.SchedulingContext;

/**
 * <p>
 * An extension of <code>{@link org.quartz.core.JobRunShell}</code> that
 * begins an XA transaction before executing the Job, and commits (or
 * rolls-back) the transaction after execution completes.
 * </p>
 * 
 * @see org.quartz.core.JobRunShell
 * 
 * @author James House
 */
public class JTAJobRunShell extends JobRunShell {

    /*
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     * 
     * Data members.
     * 
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     */

    private UserTransaction ut;

    private UserTransactionHelper userTxHelper;

    /*
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     * 
     * Constructors.
     * 
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     */

    /**
     * <p>
     * Create a JTAJobRunShell instance with the given settings.
     * </p>
     */
    public JTAJobRunShell(JobRunShellFactory jobRunShellFactory,
            Scheduler scheduler, SchedulingContext schdCtxt,
            UserTransactionHelper userTxHelper) {
        super(jobRunShellFactory, scheduler, schdCtxt);

        this.userTxHelper = userTxHelper;
    }

    /*
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     * 
     * Interface.
     * 
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     */

    protected void begin() throws SchedulerException {
        try {
            log.debug("Looking up UserTransaction.");
            ut = userTxHelper.lookup();

            log.debug("Beginning UserTransaction.");
            ut.begin();
        } catch (SchedulerException se) {
            throw se;
        } catch (Exception nse) {

            throw new SchedulerException(
                    "JTAJobRunShell could not start UserTransaction.", nse);
        }
    }

    protected void complete(boolean successfulExecution)
            throws SchedulerException {

        if (ut == null) return;

        try {
            if (ut.getStatus() == Status.STATUS_MARKED_ROLLBACK) {
                log.debug("UserTransaction marked for rollback only.");
                successfulExecution = false;
            }
        } catch (SystemException e) {
            throw new SchedulerException(
                    "JTAJobRunShell could not read UserTransaction status.", e);
        }

        if (successfulExecution) {
            try {
                log.debug("Committing UserTransaction.");
                ut.commit();
            } catch (Exception nse) {
                throw new SchedulerException(
                        "JTAJobRunShell could not commit UserTransaction.", nse);
            }
        } else {
            try {
                log.debug("Rolling-back UserTransaction.");
                ut.rollback();
            } catch (Exception nse) {
                throw new SchedulerException(
                        "JTAJobRunShell could not rollback UserTransaction.",
                        nse);
            }
        }

        ut = null;
    }

}