/*
 * The contents of this file are subject to the terms
 * of the Common Development and Distribution License
 * (the "License").  You may not use this file except
 * in compliance with the License.
 *
 * You can obtain a copy of the license at
 * https://jaxp.dev.java.net/CDDLv1.0.html.
 * See the License for the specific language governing
 * permissions and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL
 * HEADER in each file and include the License file at
 * https://jaxp.dev.java.net/CDDLv1.0.html
 * If applicable add the following below this CDDL HEADER
 * with the fields enclosed by brackets "[]" replaced with
 * your own identifying information: Portions Copyright
 * [year] [name of copyright owner]
 */

/*
 * $Id: XMLEntityReader.java,v 1.3 2005/11/03 17:02:21 jeffsuttor Exp $
 * @(#)SchemaFactoryFinder.java	1.18 05/11/17
 *
 * Copyright 2006 Sun Microsystems, Inc. All Rights Reserved.
 */

package javax.xml.validation;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Properties;

/**
 * Implementation of {@link SchemaFactory#newInstance(String)}.
 * 
 * @author <a href="Kohsuke.Kawaguchi@Sun.com">Kohsuke Kawaguchi</a>
 * @version $Revision: 1.5 $, $Date: 2005/10/06 05:39:24 $
 * @since 1.5
 */
class SchemaFactoryFinder  {

    /** debug support code. */
    private static boolean debug = false;
    /**
     *<p> Take care of restrictions imposed by java security model </p>
     */
    private static SecuritySupport ss = new SecuritySupport();
    /**
     * <p>Cache properties for performance.</p>
     */
	private static Properties cacheProps = new Properties();
    
	/**
	 * <p>First time requires initialization overhead.</p>
	 */
	private static boolean firstTime = true;
    
    static {
        // Use try/catch block to support applets
        try {
            debug = ss.getSystemProperty("jaxp.debug") != null;
        } catch (Exception _) {
            debug = false;
        }
    }

    /**
     * <p>Conditional debug printing.</p>
     * 
     * @param msg to print
     */
    private static void debugPrintln(String msg) {
        if (debug) {
            System.err.println("JAXP: " + msg);
        }
    }
    
    /**
     * <p><code>ClassLoader</code> to use to find <code>SchemaFactory</code>.</p>
     */
    private final ClassLoader classLoader;
    
    /**
     * <p>Constructor that specifies <code>ClassLoader</code> to use
     * to find <code>SchemaFactory</code>.</p>
     * 
     * @param loader
     *      to be used to load resource, {@link SchemaFactory}, and
     *      {@link SchemaFactoryLoader} implementations during