/* $Id: DownloadURLConnection.java 4510 2006-08-18 16:13:32Z 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;import java.io.BufferedInputStream;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import java.net.URL;import java.net.URLConnection;import java.util.logging.Level;import java.util.logging.Logger;import org.archive.util.ProcessUtils;import org.archive.util.ProcessUtils.ProcessResult;/** * An URL Connection that pre-downloads URL reference before passing back a * Stream reference.  When closed, it removes the local download file. * @author stack * @version $Date: 2006-08-18 16:13:32 +0000 (Fri, 18 Aug 2006) $, $Revision: 4510 $ */public abstract class DownloadURLConnection extends URLConnection {    private final String CLASSNAME = DownloadURLConnection.class.getName();    private final Logger LOGGER = Logger.getLogger(CLASSNAME);    private static final File TMPDIR =        new File(System.getProperty("java.io.tmpdir", "/tmp"));    private File downloadFile = null;    protected DownloadURLConnection(URL u) {        super(u);    }        protected String getScript() {    	return System.getProperty(this.getClass().getName() + ".path",    		"UNDEFINED");    }        protected String [] getCommand(final URL thisUrl,    		final File downloadFile) {    	return new String[] {getScript(), thisUrl.getPath(),        	downloadFile.getAbsolutePath()};      }    /**     * Do script copy to local file.     * File is available via {@link #getFile()}.     * @throws IOException      */    public void connect() throws IOException {        if (this.connected) {            return;        }                this.downloadFile = File.createTempFile(CLASSNAME, null, TMPDIR);        try {            String [] cmd = getCommand(this.url, this.downloadFile);                if (LOGGER.isLoggable(Level.FINE)) {                StringBuffer buffer = new StringBuffer();                for (int i = 0; i < cmd.length; i++) {                    if (i > 0) {                        buffer.append(" ");                    }                    buffer.append(cmd[i]);                }                LOGGER.fine("Command: " + buffer.toString());            }            ProcessResult pr = ProcessUtils.exec(cmd);            if (pr.getResult() != 0) {                LOGGER.info(cmd + " returned non-null " + pr.getResult());            }            // Assume download went smoothly.            this.connected = true;        } catch (IOException ioe) {            // Clean up my tmp file.            this.downloadFile.delete();            this.downloadFile = null;            // Rethrow.            throw ioe;        }    }        public File getFile() {        return this.downloadFile;    }        protected void setFile(final File f) {        this.downloadFile = f;    }    public InputStream getInputStream() throws IOException {        if (!this.connected) {            connect();        }                // Return BufferedInputStream so 'delegation' is done for me, so        // I don't have to implement all IS methods and pass to my        // 'delegate' instance.        final DownloadURLConnection connection = this;        return new BufferedInputStream(new FileInputStream(this.downloadFile)) {            private DownloadURLConnection ruc = connection;            public void close() throws IOException {                super.close();                if (this.ruc != null && this.ruc.getFile()!= null &&                    this.ruc.getFile().exists()) {                    this.ruc.getFile().delete();                    this.ruc.setFile(null);                }            }        };    }}