001// Copyright 2004, 2005 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.hivemind.util;
016
017import java.io.IOException;
018import java.io.InputStream;
019import java.net.MalformedURLException;
020import java.net.URL;
021import java.util.Locale;
022
023import org.apache.hivemind.ApplicationRuntimeException;
024import org.apache.hivemind.Resource;
025
026/**
027 * An implementation of {@link org.apache.hivemind.Resource}
028 * built around a string representation of a URL.
029 *
030 * @author Howard Lewis Ship
031 */
032public class URLResource extends AbstractResource
033{
034    private URL _url;
035
036    public URLResource( URL url )
037    {
038        super( url.toString() );
039        _url = url;
040    }
041
042    public URLResource( String path )
043    {
044        super( path );
045    }
046
047    public String toString()
048    {
049        return getPath();
050    }
051
052    protected Resource newResource( String path )
053    {
054        return new URLResource( path );
055    }
056
057    public URL getResourceURL()
058    {
059        if( _url == null )
060        {
061            try
062            {
063                URL test = new URL( getPath() );
064                InputStream stream = test.openStream();
065                if( stream != null )
066                {
067                    stream.close();
068                    _url = test;
069                }
070            }
071            catch( MalformedURLException ex )
072            {
073                throw new ApplicationRuntimeException( ex );
074            }
075            catch( IOException ex )
076            {
077                // If the resource can't be opened,
078                // then return null.
079            }
080        }
081        return _url;
082    }
083
084    /**
085     * Always returns this location; no localization check occurs.
086     */
087    public Resource getLocalization( Locale locale )
088    {
089        return this;
090    }
091}