Java tutorial
/* * RHQ Management Platform * Copyright 2011, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation version 2 of the License. * * This program 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ package org.rhq.enterprise.server.drift; import java.io.BufferedOutputStream; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import javax.ejb.ActivationConfigProperty; import javax.ejb.EJB; import javax.ejb.MessageDriven; import javax.jms.Message; import javax.jms.MessageListener; import javax.jms.ObjectMessage; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.rhq.core.util.stream.StreamUtil; import org.rhq.enterprise.server.auth.SubjectManagerLocal; @MessageDriven(activationConfig = { @ActivationConfigProperty(propertyName = "destinationType", propertyValue = "javax.jms.Queue"), @ActivationConfigProperty(propertyName = "destination", propertyValue = "queue/DriftChangesetQueue"), @ActivationConfigProperty(propertyName = "acknowledgeMode", propertyValue = "Auto-acknowledge"), // this is just declarative, I think it's unnecessary @ActivationConfigProperty(propertyName = "subscriptionDurability", propertyValue = "NonDurable") }) public class DriftChangesetBean implements MessageListener { private final Log log = LogFactory.getLog(DriftChangesetBean.class); @EJB private DriftManagerLocal driftManager; @EJB private SubjectManagerLocal subjectManager; @Override public void onMessage(Message message) { try { if (log.isDebugEnabled()) { log.debug("Received drift change set message"); } ObjectMessage msg = (ObjectMessage) message; DriftUploadRequest request = (DriftUploadRequest) msg.getObject(); File tempFile = null; OutputStream os = null; InputStream is = null; try { tempFile = File.createTempFile("drift-changeset", ".zip"); os = new BufferedOutputStream(new FileOutputStream(tempFile)); is = DriftUtil.remoteStream(request.getDataStream()); StreamUtil.copy(is, os); is = null; os = null; if (log.isDebugEnabled()) { log.debug("Copied [" + request.getDataSize() + "] bytes from agent into [" + tempFile.getPath() + "]"); } driftManager.saveChangeSet(subjectManager.getOverlord(), request.getResourceId(), tempFile); } catch (IOException e) { log.error(e); } finally { if (null != tempFile) { tempFile.delete(); } DriftUtil.safeClose(os); DriftUtil.safeClose(is); } } catch (Throwable t) { // catch Throwable here, don't let anything escape as bad things can happen wrt XA/2PhaseCommit log.error("Error processing drift changeset message", t); } } }