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YAJSW is a java centric implementation of the java service wrapper by tanuki (JSW). It aims at being mostly configuration compliant with the original. It should therefore be easy to switch from JSW to YAJSW.

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/* This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library 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.  
 */
package org.rzo.yajsw.boot;

import java.net.URL;
import java.net.URLClassLoader;

/**
 * Class loader for handling YAJSW related libraries. The classloader will first
 * search the YAJSW related libraries before searching the parent (system
 * classloader). The libraries required by YAJSW will thus not be visible to the
 * application which is started within the system classloader. Exception is for
 * the interface WrapperManager and for the class WrapperManagerProxy. An
 * singleton instance of WrapperManager is visible to the application for
 * shutdown or for restart. WrapperManagerProxy is required for on application
 * startup.
 */
public class WrapperClassLoader extends URLClassLoader
{

	/** The _parent. */
	ClassLoader	_parent;

	/**
	 * Instantiates a new wrapper manager class loader.
	 * 
	 * @param urls
	 *            the urls
	 * @param parent
	 *            the parent
	 */
	public WrapperClassLoader(URL[] urls, ClassLoader parent)
	{
		super(urls, null);
		_parent = parent;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.lang.ClassLoader#loadClass(java.lang.String, boolean)
	 */
	@Override
	public synchronized Class findClass(String name) throws ClassNotFoundException
	{
		// First, check if the class has already been loaded
		Class c = findLoadedClass(name);
		if (c == null)
		{
			if (!"org.rzo.yajsw.app.WrapperManager".equals(name) && !"org.rzo.yajsw.app.WrapperManagerProxy".equals(name))
				try
				{
					c = super.findClass(name);
					//System.out.println("got wrapper class "+name);

				}
				catch (ClassNotFoundException e)
				{
					// If still not found, then invoke findClass in order
					// to find the class.
				}
		}
		if (c == null)
			if (_parent != null)
			{
				c = _parent.loadClass(name);
				//System.out.println("got main class "+name);

			}

		return c;

	}

}