/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 * 
 * // Copyright 2006-2007 Sun Microsystems, Inc. All rights reserved.
 * 
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License. You can obtain
 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
 * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
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 * When distributing the software, include this License Header Notice in each
 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
 * Sun designates this particular file as subject to the "Classpath" exception
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package oracle.toplink.essentials.ejb.cmp3.persistence;

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Collections;
import java.util.Iterator;

/**
 * This is an implementation of {@link Archive} when container returns a url
 * that is not one of the familiar URL types like file or jar URLs. So, we can
 * not recurssively walk thru' it's hierarchy. As a result {@link #getEntries()}
 * returns an empty collection.
 *
 * @author Sanjeeb.Sahoo@Sun.COM
 */
public class URLArchive implements Archive {
    /*
     * Implementation Note: This class does not have any dependency on TopLink
     * or GlassFish implementation classes. Please retain this searation.
     */

    /**
     * The URL representation of this archive.
     */
    private URL url;

    public URLArchive(URL url) {
        this.url = url;
    }

    public Iterator<String> getEntries() {
        return Collections.EMPTY_LIST.iterator();
    }

    public InputStream getEntry(String entryPath) throws IOException {
        URL subEntry = new URL(url, entryPath);
        InputStream is = null;
        try {
            is = subEntry.openStream();
        } catch (IOException ioe) {
            // we return null when entry does not exist
        }
        return is;
    }

    public URL getEntryAsURL(String entryPath) throws IOException {
        URL subEntry = new URL(url, entryPath);
        try {
            InputStream is = subEntry.openStream();
            is.close();
        } catch (IOException ioe) {
            return null; // return null when entry does not exist
        }
        return subEntry;
    }

    public URL getRootURL() {
        return url;
    }
}