001    /*
002     * Copyright 2005 Niclas Hedhman
003     * Copyright 2005-2006 Stephen J. McConnell
004     *
005     * Licensed  under the  Apache License,  Version 2.0  (the "License");
006     * you may not use  this file  except in  compliance with the License.
007     * You may obtain a copy of the License at
008     *
009     *   http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed  under the  License is distributed on an "AS IS" BASIS,
013     * WITHOUT  WARRANTIES OR CONDITIONS  OF ANY KIND, either  express  or
014     * implied.
015     *
016     * See the License for the specific language governing permissions and
017     * limitations under the License.
018     */
019    
020    package net.dpml.transit.link;
021    
022    import java.io.IOException;
023    
024    import java.net.URL;
025    import java.net.URLConnection;
026    import java.net.URLStreamHandler;
027    
028    /** 
029     * The link URL protocol handler.
030     *
031     * The <strong>link:</strong> protocol is similar to the symlink concept
032     * in Linux/Unix, where something that looks like a file points to another
033     * file. In this case, the link URL points to another URL. The resolution
034     * of the link translation is picked up from managed Transit server(s).
035     * @author <a href="http://www.dpml.net">Digital Product Meta Library</a>
036     * @version 1.0.1
037     */
038    public class Handler extends URLStreamHandler
039    {
040       /**
041        * Creation of a new transit link: protocol handler.
042        */
043        public Handler()
044        {
045        }
046    
047        // ------------------------------------------------------------------------
048        // implementation
049        // ------------------------------------------------------------------------
050    
051        /**
052         * Opens a connection to the specified URL.
053         *
054         * @param url A URL to open a connection to.
055         * @return The established connection.
056         * @throws IOException If a connection failure occurs.
057         */
058        protected URLConnection openConnection( final URL url )
059            throws IOException
060        {
061            return new LinkURLConnection( url );
062        }
063    }