/* * WebSPHINX web crawling toolkit * Copyright (C) 1998,1999 Carnegie Mellon University  *  * This library is free software; you can redistribute it * and/or modify it under the terms of the GNU Library * General Public License as published by the Free Software  * Foundation, version 2. * * WebSPHINX homepage: http://www.cs.cmu.edu/~rcm/websphinx/ */package websphinx;import java.io.File;import java.io.OutputStream;import java.io.IOException;import java.util.Date;//#ifdef JDK1.1import java.io.PrintWriter;//#endif JDK1.1/*#ifdef JDK1.0import java.io.PrintStream;#endif JDK1.0*//** * Crawling monitor that writes messages to standard output or a file. * Acts as both a CrawlListener (monitoring start and end of the crawl) * and as a LinkListener (monitoring page retrieval). */public class EventLog implements CrawlListener, LinkListener {//#ifdef JDK1.1    PrintWriter stream;//#endif JDK1.1/*#ifdef JDK1.0    PrintStream stream;#endif JDK1.0*/    boolean onlyNetworkEvents = true;    /**     * Make a EventLog that writes to standard output.     */    public EventLog () {        this (System.out);    }    /**     * Make a EventLog that writes to a stream.     */    public EventLog (OutputStream out) {/*#ifdef JDK1.0        stream = new PrintStream (out, true);#endif JDK1.0*///#ifdef JDK1.1        stream = new PrintWriter (out, true);//#endif JDK1.1    }    /**     * Make a EventLog that writes to a file.  The file is overwritten.     * @param filename File to which crawling event messages are written     */    public EventLog (String filename) throws IOException {/*#ifdef JDK1.0        stream = new PrintStream (SecurityPolicy.getPolicy ().writeFile (new File(filename), false));#endif JDK1.0*///#ifdef JDK1.1        stream = new PrintWriter (SecurityPolicy.getPolicy ().writeFile (new File(filename), false));//#endif JDK1.1    }    /**     * Set whether logger prints only network-related LinkEvents.     * If true, then the logger only prints LinkEvents where     * LinkEvent.isNetworkEvent() returns true.  If false,     * then the logger prints all LinkEvents.  Default is true.     * @param flag true iff only network LinkEvents should be logged     */    public void setOnlyNetworkEvents (boolean flag) {        onlyNetworkEvents = flag;    }    /**     * Test whether logger prints only network-related LinkEvents.     * If true, then the logger only prints LinkEvents where     * LinkEvent.isNetworkEvent() returns true.  If false,     * then the logger prints all LinkEvents.  Default is true.     * @return true iff only network LinkEvents are logged     */    public boolean getOnlyNetworkEvents () {        return onlyNetworkEvents;    }    /**     * Notify that the crawler started.     */    public void started (CrawlEvent event) {        stream.println (new Date() + ": *** started " + event.getCrawler());    }    /**     * Notify that the crawler has stopped.     */    public void stopped (CrawlEvent event) {        stream.println (new Date() + ": *** finished " + event.getCrawler());    }    /**     * Notify that the crawler's state was cleared.     */    public void cleared (CrawlEvent event) {        stream.println (new Date() + ": *** cleared " + event.getCrawler());    }    /**     * Notify that the crawler timed out.     */    public void timedOut (CrawlEvent event) {        stream.println (new Date() + ": *** timed out " + event.getCrawler());    }    /**     * Notify that the crawler paused.     */    public void paused (CrawlEvent event) {        stream.println (new Date() + ": *** paused " + event.getCrawler());    }    /**     * Notify that a link event occured.     */    public void crawled (LinkEvent event) {        switch (event.getID()) {          case LinkEvent.RETRIEVING:          case LinkEvent.DOWNLOADED:          case LinkEvent.VISITED:          case LinkEvent.ERROR:            break;          default:            if (onlyNetworkEvents)                return;            break;        }        stream.println (new Date () + ": "                        + event);        Throwable exc = event.getException();        if (exc != null && ! (exc instanceof IOException))            exc.printStackTrace (stream);    }    /**     * Create a EventLog that prints to standard error and attach it to a crawler.     * This is a convenience method.     * @param crawler Crawler to be monitored     */    public static void monitor (Crawler crawler) {        EventLog logger = new EventLog (System.err);        crawler.addCrawlListener (logger);        crawler.addLinkListener (logger);    }}