Java tutorial
/******************************************************************************* * This file is part of OpenNMS(R). * * Copyright (C) 2012 The OpenNMS Group, Inc. * OpenNMS(R) is Copyright (C) 1999-2012 The OpenNMS Group, Inc. * * OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc. * * OpenNMS(R) 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, either version 3 of the License, * or (at your option) any later version. * * OpenNMS(R) 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 OpenNMS(R). If not, see: * http://www.gnu.org/licenses/ * * For more information contact: * OpenNMS(R) Licensing <license@opennms.org> * http://www.opennms.org/ * http://www.opennms.com/ *******************************************************************************/ package com.netxforge.oss2.config; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.util.Collection; import java.util.List; import org.apache.commons.io.IOUtils; import org.exolab.castor.xml.MarshalException; import org.exolab.castor.xml.ValidationException; import org.opennms.core.utils.ConfigFileConstants; import org.opennms.core.xml.CastorUtils; import org.opennms.netmgt.config.vacuumd.Action; import org.opennms.netmgt.config.vacuumd.ActionEvent; import org.opennms.netmgt.config.vacuumd.AutoEvent; import org.opennms.netmgt.config.vacuumd.Automation; import org.opennms.netmgt.config.vacuumd.Statement; import org.opennms.netmgt.config.vacuumd.Trigger; import org.opennms.netmgt.config.vacuumd.VacuumdConfiguration; import org.springframework.util.Assert; /** * This is the singleton class used to load the configuration for the OpenNMS * Vacuumd process from the vacuumd-configuration xml file. * * <strong>Note: </strong>Users of this class should make sure the * <em>setReader()</em> method is called before calling any other method to ensure the * config is loaded before accessing other convenience methods. * * @author <a href="mailto:david@opennms.com">David Hustace </a> * @author <a href="mailto:brozow@opennms.com">Mathew Brozowski </a> * @author <a href="http://www.opennms.org/">OpenNMS </a> * @author <a href="mailto:david@opennms.com">David Hustace </a> * @author <a href="mailto:brozow@opennms.com">Mathew Brozowski </a> * @author <a href="http://www.opennms.org/">OpenNMS </a> * @author <a href="mailto:david@opennms.com">David Hustace </a> * @author <a href="mailto:brozow@opennms.com">Mathew Brozowski </a> * @author <a href="http://www.opennms.org/">OpenNMS </a> * @version $Id: $ */ public final class VacuumdConfigFactory { /** * The singleton instance of this factory */ private static VacuumdConfigFactory m_singleton = null; private static boolean m_loadedFromFile = false; /** * The config class loaded from the config file */ private VacuumdConfiguration m_config; /** * <p>Constructor for VacuumdConfigFactory.</p> * * @param stream a {@link java.io.InputStream} object. * @throws org.exolab.castor.xml.MarshalException if any. * @throws org.exolab.castor.xml.ValidationException if any. */ public VacuumdConfigFactory(InputStream stream) throws MarshalException, ValidationException { m_config = CastorUtils.unmarshal(VacuumdConfiguration.class, stream); } /** * Load the config from the default config file and create the singleton * instance of this factory. * * @exception java.io.IOException * Thrown if the specified config file cannot be read * @exception org.exolab.castor.xml.MarshalException * Thrown if the file does not conform to the schema. * @exception org.exolab.castor.xml.ValidationException * Thrown if the contents do not match the required schema. * @throws java.io.IOException if any. * @throws org.exolab.castor.xml.MarshalException if any. * @throws org.exolab.castor.xml.ValidationException if any. */ public static synchronized void init() throws IOException, MarshalException, ValidationException { if (m_singleton != null) { /* * The init method has already called, so return. * To reload, reload() will need to be called. */ return; } InputStream is = null; try { is = new FileInputStream(ConfigFileConstants.getFile(ConfigFileConstants.VACUUMD_CONFIG_FILE_NAME)); setInstance(new VacuumdConfigFactory(is)); } finally { if (is != null) { IOUtils.closeQuietly(is); } } m_loadedFromFile = true; } /** * Reload the config from the default config file * * @exception java.io.IOException * Thrown if the specified config file cannot be read/loaded * @exception org.exolab.castor.xml.MarshalException * Thrown if the file does not conform to the schema. * @exception org.exolab.castor.xml.ValidationException * Thrown if the contents do not match the required schema. * @throws java.io.IOException if any. * @throws org.exolab.castor.xml.MarshalException if any. * @throws org.exolab.castor.xml.ValidationException if any. */ public static synchronized void reload() throws IOException, MarshalException, ValidationException { if (m_loadedFromFile) { setInstance(null); init(); } } /** * Return the singleton instance of this factory. * * @return The current factory instance. * @throws java.lang.IllegalStateException * Thrown if the factory has not yet been initialized. */ public static synchronized VacuumdConfigFactory getInstance() { Assert.state(m_singleton != null, "The factory has not been initialized"); return m_singleton; } /** * Set the singleton instance of this factory. * * @param instance The factory instance to set. */ public static synchronized void setInstance(VacuumdConfigFactory instance) { m_singleton = instance; } /** * Returns a Collection of automations defined in the config * * @return a {@link java.util.Collection} object. */ public synchronized Collection<Automation> getAutomations() { return m_config.getAutomations().getAutomationCollection(); } /** * Returns a Collection of triggers defined in the config * * @return a {@link java.util.Collection} object. */ public synchronized Collection<Trigger> getTriggers() { return m_config.getTriggers().getTriggerCollection(); } /** * Returns a Collection of actions defined in the config * * @return a {@link java.util.Collection} object. */ public synchronized Collection<Action> getActions() { return m_config.getActions().getActionCollection(); } /** * Returns a Collection of named events to that may have * been configured to be sent after an automation has run. * * @return a {@link java.util.Collection} object. */ public synchronized Collection<AutoEvent> getAutoEvents() { return m_config.getAutoEvents().getAutoEventCollection(); } /** * <p>getActionEvents</p> * * @return a {@link java.util.Collection} object. */ public synchronized Collection<ActionEvent> getActionEvents() { return m_config.getActionEvents().getActionEventCollection(); } /** * <p>getPeriod</p> * * @return a int. */ public synchronized int getPeriod() { return m_config.getPeriod(); } /** * Returns a Trigger with a name matching the string parameter * * @param triggerName a {@link java.lang.String} object. * @return a {@link org.opennms.netmgt.config.vacuumd.Trigger} object. */ public synchronized Trigger getTrigger(String triggerName) { for (Trigger trig : getTriggers()) { if (trig.getName().equals(triggerName)) { return trig; } } return null; } /** * Returns an Action with a name matching the string parmater * * @param actionName a {@link java.lang.String} object. * @return a {@link org.opennms.netmgt.config.vacuumd.Action} object. */ public synchronized Action getAction(String actionName) { for (Action act : getActions()) { if (act.getName().equals(actionName)) { return act; } } return null; } /** * Returns an Automation with a name matching the string parameter * * @param autoName a {@link java.lang.String} object. * @return a {@link org.opennms.netmgt.config.vacuumd.Automation} object. */ public synchronized Automation getAutomation(String autoName) { for (Automation auto : getAutomations()) { if (auto.getName().equals(autoName)) { return auto; } } return null; } /** * Returns the AutoEvent associated with the auto-event-name * * @deprecated Use {@link ActionEvent} objects instead. Access these objects with {@link #getActionEvent(String)}. * @param name a {@link java.lang.String} object. * @return a {@link org.opennms.netmgt.config.vacuumd.AutoEvent} object. */ public synchronized AutoEvent getAutoEvent(String name) { for (AutoEvent ae : getAutoEvents()) { if (ae.getName().equals(name)) { return ae; } } return null; } /** * <p>getSqlStatements</p> * * @return an array of {@link java.lang.String} objects. */ public synchronized String[] getSqlStatements() { Statement[] stmts = m_config.getStatement(); String[] sql = new String[stmts.length]; for (int i = 0; i < stmts.length; i++) { sql[i] = stmts[i].getContent(); } return sql; } /** * <p>getStatements</p> * * @return a {@link java.util.List} object. */ public synchronized List<Statement> getStatements() { return m_config.getStatementCollection(); } /** * <p>getActionEvent</p> * * @param name a {@link java.lang.String} object. * @return a {@link org.opennms.netmgt.config.vacuumd.ActionEvent} object. */ public ActionEvent getActionEvent(String name) { for (ActionEvent actionEvent : getActionEvents()) { if (actionEvent.getName().equals(name)) { return actionEvent; } } return null; } }