/*
 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */

package com.sun.xml.internal.ws.transport.http;

import java.net.URL;
import java.net.MalformedURLException;
import java.util.Set;

/**
 * Used to locate resources for {@link DeploymentDescriptorParser}.
 *
 * <p>
 * This allows {@link DeploymentDescriptorParser} to be used outside a servlet container,
 * but it still needs to work with a layout similar to the web application.
 * If this can be abstracted away better, that would be nice.
 *
 * @author Kohsuke Kawaguchi
 */
public interface ResourceLoader {
    /**
     * Returns the actual location of the resource from the 'path'
     * that represents a virtual locaion of a file inside a web application.
     *
     * @param path
     *      Desiganates an absolute path within an web application, such as:
     *      '/WEB-INF/web.xml' or some such.
     *
     * @return
     *      the actual location, if found, or null if not found.
     */
    URL getResource(String path) throws MalformedURLException;

    /**
     * Gets the catalog XML file that should be consulted when
     * loading resources from this {@link ResourceLoader}.
     */
    URL getCatalogFile() throws MalformedURLException;

    /**
     * Returns the list of files in the given directory.
     *
     * @return
     *      null if the path is invalid. empty if the path didn't contain
     *      any entry in it.
     *
     * @see javax.servlet.http.ServletContext#getResourcePaths(String)
     */
    Set<String> getResourcePaths(String path);
}
