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1   /* DevUtils
2    *
3    * Created on Oct 29, 2003
4    *
5    * Copyright (C) 2003 Internet Archive.
6    *
7    * This file is part of the Heritrix web crawler (crawler.archive.org).
8    *
9    * Heritrix is free software; you can redistribute it and/or modify
10   * it under the terms of the GNU Lesser Public License as published by
11   * the Free Software Foundation; either version 2.1 of the License, or
12   * any later version.
13   *
14   * Heritrix is distributed in the hope that it will be useful,
15   * but WITHOUT ANY WARRANTY; without even the implied warranty of
16   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17   * GNU Lesser Public License for more details.
18   *
19   * You should have received a copy of the GNU Lesser Public License
20   * along with Heritrix; if not, write to the Free Software
21   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
22   */
23  package org.archive.util;
24  
25  import java.io.BufferedReader;
26  import java.io.IOException;
27  import java.io.InputStreamReader;
28  import java.io.PrintWriter;
29  import java.io.StringWriter;
30  import java.util.logging.Logger;
31  
32  
33  /***
34   * Write a message and stack trace to the 'org.archive.util.DevUtils' logger.
35   *
36   * @author gojomo
37   * @version $Revision: 4644 $ $Date: 2006-09-20 22:40:21 +0000 (Wed, 20 Sep 2006) $
38   */
39  public class DevUtils {
40      public static Logger logger =
41          Logger.getLogger(DevUtils.class.getName());
42  
43      /***
44       * Log a warning message to the logger 'org.archive.util.DevUtils' made of
45       * the passed 'note' and a stack trace based off passed exception.
46       *
47       * @param ex Exception we print a stacktrace on.
48       * @param note Message to print ahead of the stacktrace.
49       */
50      public static void warnHandle(Throwable ex, String note) {
51          logger.warning(TextUtils.exceptionToString(note, ex));
52      }
53  
54      /***
55       * @return Extra information gotten from current Thread.  May not
56       * always be available in which case we return empty string.
57       */
58      public static String extraInfo() {
59          StringWriter sw = new StringWriter();
60          PrintWriter pw = new PrintWriter(sw); 
61          final Thread current = Thread.currentThread();
62          if (current instanceof Reporter) {
63              Reporter tt = (Reporter)current;
64              try {
65                  tt.reportTo(pw);
66              } catch (IOException e) {
67                  // Not really possible w/ a StringWriter
68                  e.printStackTrace();
69              } 
70          }
71          if (current instanceof ProgressStatisticsReporter) {
72              ProgressStatisticsReporter tt = (ProgressStatisticsReporter)current;
73              try {
74                  tt.progressStatisticsLegend(pw);
75                  tt.progressStatisticsLine(pw);
76              } catch (IOException e) {
77                  // Not really possible w/ a StringWriter
78                  e.printStackTrace();
79              }
80          }
81          pw.flush();
82          return sw.toString();
83      }
84  
85      /***
86       * Nothing to see here, move along.
87       * @deprecated  This method was never used.
88       */
89      @Deprecated
90      public static void betterPrintStack(RuntimeException re) {
91          re.printStackTrace(System.err);
92      }
93      
94      /***
95       * Send this JVM process a SIGQUIT; giving a thread dump and possibly
96       * a heap histogram (if using -XX:+PrintClassHistogram).
97       * 
98       * Used to automatically dump info, for example when a serious error
99       * is encountered. Would use 'jmap'/'jstack', but have seen JVM
100      * lockups -- perhaps due to lost thread wake signals -- when using
101      * those against Sun 1.5.0+03 64bit JVM. 
102      */
103     public static void sigquitSelf() {
104         try {
105             Process p = Runtime.getRuntime().exec(
106                     new String[] {"perl", "-e", "print getppid(). \"\n\";"});
107             BufferedReader br =
108                 new BufferedReader(new InputStreamReader(p.getInputStream()));
109             String ppid = br.readLine();
110             Runtime.getRuntime().exec(
111                     new String[] {"sh", "-c", "kill -3 "+ppid}).waitFor();
112         } catch (IOException e) {
113             // TODO Auto-generated catch block
114             e.printStackTrace();
115         } catch (InterruptedException e) {
116             // TODO Auto-generated catch block
117             e.printStackTrace();
118         }
119     }
120 }