/*
    * 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.net.URL;
  import java.net.URLClassLoader;
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Properties;
  import java.util.Set;
  
  import javax.management.MalformedObjectNameException;
  import javax.management.ObjectName;
  
  import ch.elca.el4j.services.monitoring.notification.CoreNotificationHelper;
  import ch.elca.el4j.util.classpath.DuplicateClassFinder;
  
  /**
   * The proxy class for the JVM. Each MBean Server contains exactly one JVM
   * MBean.
   *
   * @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/JvmMB.java $
   *
   * @author Raphael Boog (RBO)
   * @author Rashid Waraich (RWA)
   */
  public class JvmMB implements JvmMBMBean {
  
  	/**
  	 * The domain of the JVM proxy as it will be registered at the MBean Server.
  	 */
  	public static final String JVM_DOMAIN = "JVM";
  
  	/**
  	 * The counter on the number of JVMs.
  	 */
  	private static int s_counter = 1;
  
  	/**
  	 * A list of Application Context proxies which are running in this JVM
  	 * proxy.
  	 */
  	protected List m_applicationContextMB = new ArrayList();
  
  	/**
  	 * The object name of this object.
  	 */
  	private ObjectName m_objectName;
  
  	/**
  	 * The instance counter of this object.
  	 */
  	private int m_instanceCounter;
  
  	/**
  	 * Constructor which calls the setObjectName() method.
  	 *
  	 */
  	public JvmMB() {
  
  		// Set the instanceCounter.
  		setInstanceCounter();
  
  		// Set the object name of this object.
  		setObjectName();
  
  	}
  
  	/**
  	 * {@inheritDoc}
  	 */
  	public String[] getSystemProperties() {
  		Properties systemProperties = System.getProperties();
  
  		Set keySet = systemProperties.keySet();
  		String[] result = new String[keySet.size()];
  		Iterator iter = keySet.iterator();
  		int j = 0;
  
  		while (iter.hasNext()) {
  			Object key = iter.next();
  			result[j] = (String) key + " = " + systemProperties.get(key);
  			j++;
 		}
 
 		return result;
 
 	}
 
 	/** {@inheritDoc} */
 	public String[] getClassPath() {
 		String[] cp;
 		ClassLoader myLoader = JvmMB.class.getClassLoader();
 		if (myLoader instanceof URLClassLoader) {
 			// This is an URLClassLoader, so get the urls.
 			URL[] urls = ((URLClassLoader) myLoader).getURLs();
 			cp = new String[urls.length];
 			for (int i = 0; i < urls.length; i++) {
 				cp[i] = urls[i].toExternalForm();
 			}
 			return cp;
 		} else {
 			// Not an URLClassLoader. Try returning the System cp.
 			return System.getProperty("java.class.path")
 				.split(System.getProperty("path.separator"));
 		}
 	}
 	
 	/** {@inheritDoc} */
 	public String findDuplicateClasses() {
 		DuplicateClassFinder finder = new DuplicateClassFinder();
 		finder.addClass(JvmMB.class);
 		finder.search();
 		String report;
 		if (finder.duplicatesFound()) {
 			report = "Duplicate classes found: \n";
 			Set<String> duplicates = finder.getAllDuplicates();
 			for (String current : duplicates) {
 				report += "Class: " + current + "\n";
 				for (String loc : finder.getLocations(current)) {
 					report += "  " + loc + "\n";
 				}
 				report += "\n";
 			}
 		} else {
 			report = "No duplicate classes were found.";
 		}
 		return report;
 	}
 	
 	/**
 	 * {@inheritDoc}
 	 */
 	public ObjectName[] getApplicationContexts() {
 
 		ObjectName[] result = new ObjectName[m_applicationContextMB.size()];
 
 		for (int i = 0; i < result.length; i++) {
 			ApplicationContextMB acLocal
 				= (ApplicationContextMB) m_applicationContextMB.get(i);
 			result[i] = acLocal.getObjectName();
 
 		}
 		return result;
 	}
 
 	/**
 	 * Add an Application Context proxy to the list of Application Context
 	 * proxies in this JVM proxy.
 	 *
 	 * @param appCont
 	 *            The Application Context proxy to add
 	 */
 	@SuppressWarnings("unchecked")
 	public void addApplicationContext(ApplicationContextMB appCont) {
 		this.m_applicationContextMB.add(appCont);
 	}
 
 	/**
 	 * Sets the object name of this JVM proxy.
 	 *
 	 */
 	public void setObjectName() {
 
 		String name
 			= JVM_DOMAIN + ":name=jvmRootMonitor " + getInstanceCounter();
 
 		try {
 			m_objectName = new ObjectName(name);
 		} catch (MalformedObjectNameException e) {
 			CoreNotificationHelper.notifyMisconfiguration(
 					"The string passed as a parameter does not have"
 					+ " the right format.", e);
 		}
 	}
 
 	/**
 	 * The getter method for the object name of this JVM proxy.
 	 *
 	 * @return The object name of this JVM proxy
 	 */
 	public ObjectName getObjectName() {
 		return m_objectName;
 	}
 
 	/**
 	 * The getter method for the instanceCounter member.
 	 *
 	 * @return The instanceCounter member
 	 */
 	public int getInstanceCounter() {
 		return m_instanceCounter;
 	}
 
 	/**
 	 * Save the class variable s_counter to an instance member and increment the
 	 * class variable by 1.
 	 *
 	 */
 	public void setInstanceCounter() {
 
 		synchronized (JvmMB.class) {
 			m_instanceCounter = s_counter;
 			s_counter++;
 		}
 
 	}
 	
 	/**
 	 * {@inheritDoc}
 	 */
 	public String showThreadTable() {
 		// Checkstyle: MagicNumber off
 		Thread[] threads = getAllThreads();
 		String[][] cells = new String[threads.length + 1][7];
 		
 		cells[0][0] = "Thread Id";
 		cells[0][1] = "Name";
 		cells[0][2] = "isDeamon";
 		cells[0][3] = "State";
 		cells[0][4] = "Thread Group";
 		cells[0][5] = "Priority";
 		cells[0][6] = "Stack Trace";
 		
 		for (int i = 0; i < threads.length; i++) {
 			cells[i + 1][0] = Long.toString(threads[i].getId());
 			cells[i + 1][1] = threads[i].getName();
 			cells[i + 1][2] = Boolean.toString(threads[i].isDaemon());
 			cells[i + 1][3] = threads[i].getState().toString();
 			cells[i + 1][4] = threads[i].getThreadGroup().getName();
 			cells[i + 1][5] = Integer.toString(threads[i].getPriority());
 			cells[i + 1][6]
 				= stackTraceElementsToString(threads[i].getStackTrace());
 		}
 		// Checkstyle: MagicNumber on
 		return JmxHtmlFormatter.getHtmlTable(cells);
 	}
 	
 	
 	/**
 	 * Converts an array of stacktrace elements to a string.
 	 * @param trace The stacktrace array to convert
 	 * @return The resulting string
 	 */
 	private String stackTraceElementsToString(StackTraceElement[] trace) {
 		String result = "";
 		
 		for (int i = 0; i < trace.length; i++) {
 			result = result.concat(trace[i].toString());
 		}
 		
 		return result;
 	}
 	
 	
 	/**
 	 * @return An array of all current threads.
 	 */
 	private Thread[] getAllThreads() {
 		return Thread.getAllStackTraces().keySet().toArray(new Thread[1]);
 	}
 	
 	
 	
 	
 }