/*
    * EL4J, the Extension Library for the J2EE, adds incremental enhancements to
    * the spring framework, http://el4j.sf.net
    * Copyright (C) 2005 by ELCA Informatique SA, Av. de la Harpe 22-24,
    * 1000 Lausanne, Switzerland, http://www.elca.ch
    *
    * EL4J is published under the GNU Lesser General Public License (LGPL)
    * Version 2.1. See http://www.gnu.org/licenses/
    *
   * 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 Lesser General Public License for more details.
   *
   * For alternative licensing, please contact info@elca.ch
   */
  
  package ch.elca.el4j.services.monitoring.jmx;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import javax.management.InstanceAlreadyExistsException;
  import javax.management.MBeanRegistrationException;
  import javax.management.MBeanServer;
  import javax.management.MalformedObjectNameException;
  import javax.management.NotCompliantMBeanException;
  import javax.management.ObjectName;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.beans.factory.BeanFactory;
  import org.springframework.context.ApplicationContext;
  
  import ch.elca.el4j.core.context.ModuleApplicationContext;
  import ch.elca.el4j.core.exceptions.BaseException;
  import ch.elca.el4j.services.monitoring.notification.CoreNotificationHelper;
  
  import ch.elca.el4j.util.classpath.ClassloaderTools;
  import ch.elca.el4j.util.codingsupport.Reject;
  
  /**
   * The proxy class for an ApplicationContext.
   *
   * @svnLink $Revision: 4010 $;$Date: 2009-12-01 10:59:54 +0100 (Di, 01. Dez 2009) $;$Author: jonasha $;$URL: https://el4j.svn.sourceforge.net/svnroot/el4j/branches/el4j_3_1/el4j/framework/modules/jmx/src/main/java/ch/elca/el4j/services/monitoring/jmx/ApplicationContextMB.java $
   *
   * @author Raphael Boog (RBO)
   */
  public class ApplicationContextMB implements ApplicationContextMBMBean {
  
  	/**
  	 * The domain of the Application Context proxy as it will be registered at
  	 * the MBean Server.
  	 */
  	public static final String APPLICATION_CONTEXT_DOMAIN
  		= "ApplicationContext";
  
  	/**
  	 * The message to be printed in case the used Application Context is not the
  	 * ModuleApplicationContext.
  	 */
  	public static final String NOT_MODULE_APPLICATION_CONTEXT = "This context "
  		+ "was not loaded via the "
  		+ "'ch.elca.el4j.core.context.ModuleApplicationContext'. This is "
  		+ "the reason why the configuration locations cannot be displayed.";
  
  	/**
  	 * The counter on the number of Application Contexts.
  	 */
  	private static int s_counter = 1;
  
  	/**
  	 * Private logger of this class.
  	 */
  	private static Logger s_logger = LoggerFactory.getLogger(ApplicationContextMB.class);
  
  	/**
  	 * The reference to the real Application Context.
  	 */
  	protected ApplicationContext m_applicationContext;
  
  	/**
  	 * The MBean Server to which this Application Context is registered.
  	 */
  	protected MBeanServer m_mBeanServer;
  
  	/**
  	 * The Bean Factory belonging to this Application Context.
  	 */
  	protected BeanFactory m_beanFactory;
  
  	/**
  	 * The instance counter of this object.
  	 */
  	private int m_instanceCounter;
  
  	/**
  	 * An array of spring beans registered to this Application Context.
  	 */
 	private SpringBeanMB[] m_springBeanMB;
 
 	/**
 	 * The object name of this Application Context.
 	 */
 	private ObjectName m_objectName;
 
 	/**
 	 * The proxy JVM in which this Application Context is running.
 	 */
 	private JvmMB m_jvmmb;
 
 	/**
 	 * Constructor.
 	 *
 	 * @param applicationContext
 	 *            The Application Context to which this class is a proxy.
 	 * @param beanFactory
 	 *            The Bean Factory belonging to this Application Context.
 	 * @param mBeanServer
 	 *            The MBean Server to which this Application Context is
 	 *            registered.
 	 * @param jvmmb
 	 *            The proxy JVM in which this Application Context is running.
 	 */
 	public ApplicationContextMB(ApplicationContext applicationContext,
 		BeanFactory beanFactory, MBeanServer mBeanServer, JvmMB jvmmb) {
 
 		this.m_applicationContext = applicationContext;
 		this.m_beanFactory = beanFactory;
 		this.m_mBeanServer = mBeanServer;
 		this.m_jvmmb = jvmmb;
 
 	}
 
 	/**
 	 * Init method. Sets up this ApplicationContextMB.
 	 *
 	 * @throws BaseException
 	 *             in case the initialization failed
 	 */
 	public void init() throws BaseException {
 
 		String[] beanDefinitionNames = m_applicationContext
 			.getBeanDefinitionNames();
 
 		// Set the instanceCounter.
 		setInstanceCounter();
 
 		// Set the object name of this object.
 		setObjectName();
 
 		int cnt = m_applicationContext.getBeanDefinitionCount();
 
 		m_springBeanMB = new SpringBeanMB[cnt];
 
 		// Create and initialized a Log4jConfig object.
 		Log4jConfig logConfig = new Log4jConfig("log4jConfig", this,
 			m_applicationContext, m_beanFactory, m_mBeanServer);
 		logConfig.init();
 	 
 		// Create the proxies of the SpringBeans loaded by this Application
 		// Context.
 		for (int i = 0; i < cnt; i++) {
 			m_springBeanMB[i] = new SpringBeanMB(beanDefinitionNames[i], this,
 				m_applicationContext, m_beanFactory, m_mBeanServer);
 			m_springBeanMB[i].init();
 		}
 
 		// Register the Application Context at the MBean Server.
 		registerApplicationContext();
 
 		// Add this Application Context proxy to the JVM proxy.
 		registerAtJvmMB();
 
 	}
 
 	/**
 	 * Register this ApplicationContext at the MBean Server.
 	 *
 	 * @throws BaseException
 	 *             in case the registration at the MBean Server failed
 	 */
 	protected void registerApplicationContext() throws BaseException {
 
 		Reject.ifNull(getObjectName(), "The object name of the "
 				+ "ApplicationContextMB '" + this.toString()
 				+ "' should not be null.");
 
 		try {
 			m_mBeanServer.registerMBean(this, getObjectName());
 		} catch (InstanceAlreadyExistsException e) {
 			String message = "The MBean is already under the control"
 				+ " of the MBean server.";
 			s_logger.error(message);
 			throw new BaseException(message, e);
 		} catch (MBeanRegistrationException e) {
 			String message = "The MBean will not be registered.";
 			s_logger.error(message);
 			throw new BaseException(message, e);
 		} catch (NotCompliantMBeanException e) {
 			String message = "This object is not a JMX compliant MBean.";
 			s_logger.error(message);
 			throw new BaseException(message, e);
 		}
 	}
 
 	/**
 	 * Register this ApplicationContext at the JVM MBean.
 	 *
 	 */
 	protected void registerAtJvmMB() {
 		m_jvmmb.addApplicationContext(this);
 	}
 
 	/**
 	 * Set the objectName of this ApplicationContext.
 	 *
 	 */
 	protected void setObjectName() {
 
 		// valid JMX key properties must not contain any of these chars
 		// :",=*?  (JMX specs v1.2, p110)
 		String dispName = getName().replaceAll("[:\\\",=*?]", " ");
 		
 		// Create the object name String.
 		String name = APPLICATION_CONTEXT_DOMAIN + ":name="
 			+ getInstanceCounter() + " - " + dispName;
 
 		try {
 			m_objectName = new ObjectName(name);
 		} catch (MalformedObjectNameException e) {
 			CoreNotificationHelper.notifyMisconfiguration(
 					"The string passed as a parameter does not have"
 					+ " the right format.", e);
 		}
 	}
 
 	/**
 	 * Returns the object name of the ApplicationContext.
 	 *
 	 * @return objectName The object name of this Application Context proxy.
 	 */
 	public ObjectName getObjectName() {
 		return m_objectName;
 	}
 
 	/**
 	 * Save the class variable s_counter to an instance member and increment the
 	 * class variable by 1.
 	 *
 	 */
 	public void setInstanceCounter() {
 
 		synchronized (ApplicationContextMB.class) {
 			m_instanceCounter = s_counter;
 			s_counter++;
 		}
 
 	}
 
 	/**
 	 * The getter method for the instanceCounter member.
 	 *
 	 * @return The instanceCounter member
 	 */
 	public int getInstanceCounter() {
 		return m_instanceCounter;
 	}
 
 	/**
 	 * {@inheritDoc}
 	 */
 	public String getName() {
 		return m_applicationContext.getDisplayName();
 	}
 
 	/**
 	 * {@inheritDoc}
 	 */
 	public ObjectName[] getSpringBeansMB() {
 
 		List springBeansList = new ArrayList();
 
 		for (int i = 0; i < m_springBeanMB.length; i++) {
 			if (m_mBeanServer.isRegistered(m_springBeanMB[i].getObjectName())) {
 				springBeansList.add(m_springBeanMB[i].getObjectName());
 			}
 		}
 
 		return (ObjectName[]) springBeansList
 			.toArray(new ObjectName[springBeansList.size()]);
 	}
 
 	/**
 	 * {@inheritDoc}
 	 */
 	public ObjectName getJvmMB() {
 		return m_jvmmb.getObjectName();
 	}
 
 	/**
 	 * {@inheritDoc}
 	 */
 	public String[] getResolvedConfigLocations() {
 		String[] result = null;
 		if (m_applicationContext instanceof ModuleApplicationContext) {
 			ModuleApplicationContext lac
 				= (ModuleApplicationContext) m_applicationContext;
 			result = lac.getConfigLocations();
 		} else {
 			result = new String[] {};
 		}
 		return result;
 	}
 
 	/**
 	 * {@inheritDoc}
 	 */
 	public String[] getInclusiveConfigLocations() {
 		String[] result = null;
 		if (m_applicationContext instanceof ModuleApplicationContext) {
 			ModuleApplicationContext lac
 				= (ModuleApplicationContext) m_applicationContext;
 			result = lac.getInclusiveConfigLocations();
 		} else {
 			result = new String[] {NOT_MODULE_APPLICATION_CONTEXT};
 		}
 		return result;
 	}
 
 	/**
 	 * {@inheritDoc}
 	 */
 	public String[] getExclusiveConfigLocations() {
 		String[] result = null;
 		if (m_applicationContext instanceof ModuleApplicationContext) {
 			ModuleApplicationContext lac
 				= (ModuleApplicationContext) m_applicationContext;
 			result = lac.getExclusiveConfigLocations();
 		} else {
 			result = new String[] {NOT_MODULE_APPLICATION_CONTEXT};
 		}
 		return result;
 	}
 	
 	/** {@inheritDoc} */
 	public String[] getURLClassPath() {
 		Class<?> c = m_applicationContext.getClass();
 		if (ClassloaderTools.isURLLoaded(c)) {
 			return ClassloaderTools.getURLs(c);
 		}
 		return null;
 	}
 
 	/**
 	 * Setter for the springBeanMB member.
 	 *
 	 * @param springBeanMB
 	 *            The value to set
 	 */
 	protected void setSpringBeanMB(SpringBeanMB[] springBeanMB) {
 		this.m_springBeanMB = springBeanMB;
 	}
 
 	/**
 	 * Getter for the springBeanMB member.
 	 *
 	 * @return The value of the springBeanMB member
 	 */
 	public SpringBeanMB[] getSpringBeanMB() {
 		return m_springBeanMB;
 	}
 }