Java tutorial
/* * RHQ Management Platform * Copyright (C) 2005-2008 Red Hat, Inc. * All rights reserved. * * 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.alert; import javax.ejb.EJB; import javax.ejb.Stateless; import javax.ejb.TransactionAttribute; import javax.ejb.TransactionAttributeType; import javax.persistence.EntityManager; import javax.persistence.PersistenceContext; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.rhq.core.domain.alert.AlertDampeningEvent; import org.rhq.core.domain.alert.AlertDefinition; import org.rhq.enterprise.server.RHQConstants; import org.rhq.enterprise.server.alert.engine.jms.model.AbstractAlertConditionMessage; import org.rhq.enterprise.server.alert.engine.jms.model.ActiveAlertConditionMessage; import org.rhq.enterprise.server.alert.engine.jms.model.InactiveAlertConditionMessage; /** * see {@link CachedConditionManagerLocal#processCachedConditionMessage( * org.rhq.enterprise.server.alert.engine.jms.model.AbstractAlertConditionMessage, Integer)} * for more information. * * @author Joseph Marques */ @Stateless public class CachedConditionManagerBean implements CachedConditionManagerLocal { private final Log log = LogFactory.getLog(CachedConditionManagerBean.class); @PersistenceContext(unitName = RHQConstants.PERSISTENCE_UNIT_NAME) private EntityManager entityManager; @EJB private AlertDefinitionManagerLocal alertDefinitionManager; @EJB private AlertConditionLogManagerLocal alertConditionLogManager; @TransactionAttribute(TransactionAttributeType.REQUIRES_NEW) public void processCachedConditionMessage(AbstractAlertConditionMessage conditionMessage, Integer definitionId) { /* * note that ctime is the time when the condition was known to be true, not the time we're persisting the * condition log message */ if (conditionMessage instanceof ActiveAlertConditionMessage) { ActiveAlertConditionMessage activeConditionMessage = (ActiveAlertConditionMessage) conditionMessage; if (alertDefinitionManager.isEnabled(definitionId) == false) { if (log.isDebugEnabled()) { log.debug("AlertDefinition[id=" // + activeConditionMessage.getAlertConditionId() // + "] was already disabled " // + "(likely due to recovery logic disablement on earlier messages in this process batch), " // + "ignoring " // + activeConditionMessage); } return; } alertConditionLogManager.updateUnmatchedLogByAlertConditionId( activeConditionMessage.getAlertConditionId(), activeConditionMessage.getTimestamp(), activeConditionMessage.getValue()); alertConditionLogManager .checkForCompletedAlertConditionSet(activeConditionMessage.getAlertConditionId()); } else if (conditionMessage instanceof InactiveAlertConditionMessage) { // first do some bookkeeping by removing partially matched condition logs alertConditionLogManager.removeUnmatchedLogByAlertConditionId(conditionMessage.getAlertConditionId()); // then create a NEGATIVE dampening event, to breakup any contiguous POSITIVE events for correct processing AlertDefinition flyWeightDefinition = new AlertDefinition(); flyWeightDefinition.setId(definitionId); AlertDampeningEvent event = new AlertDampeningEvent(flyWeightDefinition, AlertDampeningEvent.Type.NEGATIVE); entityManager.persist(event); } else { log.error("Unsupported message type sent to consumer for processing: " + conditionMessage.getClass().getSimpleName()); } } }