/* $Id: Handler.java 4566 2006-08-31 16:51:41Z stack-sf $ * * Created August 11th, 2006 * * Copyright (C) 2006 Internet Archive. * * This file is part of the Heritrix web crawler (crawler.archive.org). * * Heritrix is free software; you can redistribute it and/or modify * it under the terms of the GNU Lesser Public License as published by * the Free Software Foundation; either version 2.1 of the License, or * any later version. * * Heritrix 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 Lesser Public License for more details. * * You should have received a copy of the GNU Lesser Public License * along with Heritrix; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */package org.archive.net.md5;import java.io.IOException;import java.io.InputStream;import java.net.URL;import java.net.URLConnection;import java.net.URLStreamHandler;/** * A protocol handler for an 'md5' URI scheme. * Md5 URLs look like this: <code>md5:deadbeefdeadbeefdeadbeefdeadbeef</code> * When this handler is invoked against an md5 URL, it passes the raw md5 to  * the configured script as an argument.  The configured script then does the * work to bring the item pointed to by the md5 local so we can open a Stream * on the local copy.  Local file is deleted when we finish. Do * {@link org.archive.net.DownloadURLConnection#getFile()} to get name of * temporary file. *  * <p>You need to define the system property * <code>-Djava.protocol.handler.pkgs=org.archive.net</code> to add this handler * to the java.net.URL set. Also define system properties * <code>-Dorg.archive.net.md5.Md5URLConnection.path=PATH_TO_SCRIPT</code> to * pass path of script to run as well as * <code>-Dorg.archive.net.md5.Md5URLConnection.options=OPTIONS</code> for * any options you'd like to include.  The pointed-to PATH_TO_SCRIPT * will be invoked as follows: <code>PATH_TO_SCRIPT OPTIONS MD5 * LOCAL_TMP_FILE</code>.  The LOCAL_TMP_FILE file is made in * <code>java.io.tmpdir</code> using java tmp name code. * @author stack */public class Handler extends URLStreamHandler {    protected URLConnection openConnection(URL u) {        return new Md5URLConnection(u);    }    /**     * Main dumps rsync file to STDOUT.     * @param args     * @throws IOException     */    public static void main(String[] args)    throws IOException {          if (args.length != 1) {            System.out.println("Usage: java java " +                "-Djava.protocol.handler.pkgs=org.archive.net " +                "org.archive.net.md5.Handler " +                "md5:deadbeefdeadbeefdeadbeefdeadbeef");            System.exit(1);        }        System.setProperty("org.archive.net.md5.Md5URLConnection.path",            "/tmp/manifest");        System.setProperty("java.protocol.handler.pkgs", "org.archive.net");        URL u = new URL(args[0]);        URLConnection connect = u.openConnection();        // Write download to stdout.        final int bufferlength = 4096;        byte [] buffer = new byte [bufferlength];        InputStream is = connect.getInputStream();        try {            for (int count = is.read(buffer, 0, bufferlength);                    (count = is.read(buffer, 0, bufferlength)) != -1;) {                System.out.write(buffer, 0, count);            }            System.out.flush();        } finally {            is.close();        }    }}