NameSpaceWalker - utility for dumping a web application's JNDI context to the servlet context log

NameSpaceWalker.java

package org.jonseymour.servlet;

import java.util.logging.Level;
import java.util.logging.Logger;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NameClassPair;
import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.servlet.ServletContext;
import javax.servlet.ServletContextEvent;

public class NameSpaceWalker {

	/**
	 * Recursively dump the JNDI namespace of a webapp to the servlet context log.
	 * <p>
	 * To use, add:
	 * 
	 * <xmp>
	 *   <listener>
	 * 		<listener-class>org.jonseymour.servlet.NameSpaceWalker$ServletContextListener</listener-class>
	 *   </listener>
	 * </xmp>
	 * 
	 * to your web.xml
	 * 
	 * @author jonseymour
	 */
	static public class ServletContextListener implements javax.servlet.ServletContextListener {

		@Override
		public void contextDestroyed(ServletContextEvent arg0) {
		}

		@Override
		public void contextInitialized(final ServletContextEvent arg0) {
			final ServletContext servletContext = arg0.getServletContext();
			try 
			{
				final NameSpaceWalker walker = new NameSpaceWalker(new InitialContext())
				{
					protected void log(final String msg)
					{
						servletContext.log(msg);					
					}
				};
				walker.walk();
			} 
			catch (NamingException e) 
			{
				servletContext.log(e.getMessage(), e);
			}
			
		}
	}
		
	private final Context context;
	
	public NameSpaceWalker(final Context context)
	{
		this.context = context;
	}
	
	public void walk(final String contextName)
	{
		try {
			final NamingEnumeration<NameClassPair> names = context
					.list(contextName);
			for (; names.hasMore();) {
				final NameClassPair name;
				final String bindingName;
				final String className;
				final String fullName;

				name = names.next();
				bindingName = name.getName();
				className = name.getClassName();

				if (contextName.endsWith(":")) {
					fullName = contextName + bindingName;
				} else {
					fullName = contextName + "/" + bindingName;
				}

				log("JNDI name " + fullName + "," + className);

				walk(fullName);					
			}
		} catch (NamingException n) {
			log("not a naming context: " + contextName);
		}
	}
	
	public void walk()
	{
		walk("java:");
		walk("ejblocal:");
	}

	protected void log(final String msg) 
	{
		Logger.getLogger(NameSpaceWalker.class.getName()).log(Level.INFO, msg);
	}
}