libjava/java/util/logging/ConsoleHandler.java

   1 /* ConsoleHandler.java -- a class for publishing log messages to System.err
   2    Copyright (C) 2002, 2004 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package java.util.logging;
  40
  41 /**
  42  * A <code>ConsoleHandler</code> publishes log records to
  43  * <code>System.err</code>.
  44  *
  45  * <p><strong>Configuration:</strong> Values of the subsequent
  46  * <code>LogManager</code> properties are taken into consideration
  47  * when a <code>ConsoleHandler</code> is initialized.
  48  * If a property is not defined, or if it has an invalid
  49  * value, a default is taken without an exception being thrown.
  50  *
  51  * <ul>
  52  *
  53  * <li><code>java.util.logging.ConsoleHandler.level</code> - specifies
  54  *     the initial severity level threshold. Default value:
  55  *     <code>Level.INFO</code>.</li>
  56  *
  57  * <li><code>java.util.logging.ConsoleHandler.filter</code> - specifies
  58  *     the name of a Filter class. Default value: No Filter.</li>
  59  *
  60  * <li><code>java.util.logging.ConsoleHandler.formatter</code> - specifies
  61  *     the name of a Formatter class. Default value:
  62  *     <code>java.util.logging.SimpleFormatter</code>.</li>
  63  *
  64  * <li><code>java.util.logging.ConsoleHandler.encoding</code> - specifies
  65  *     the name of the character encoding. Default value:
  66  *     the default platform encoding.</li>
  67  *
  68  * </ul>
  69  *
  70  * @author Sascha Brawer (brawer@acm.org)
  71  */
  72 public class ConsoleHandler
  73   extends StreamHandler
  74 {
  75   /**
  76    * Constructs a <code>StreamHandler</code> that publishes
  77    * log records to <code>System.err</code>.  The initial
  78    * configuration is determined by the <code>LogManager</code>
  79    * properties described above.
  80    */
  81   public ConsoleHandler()
  82   {
  83     super(System.err, "java.util.logging.ConsoleHandler", Level.INFO,
  84          /* formatter */ null, SimpleFormatter.class);
  85   }
  86
  87
  88   /**
  89    * Forces any data that may have been buffered to the underlying
  90    * output device, but does <i>not</i> close <code>System.err</code>.
  91    *
  92    * <p>In case of an I/O failure, the <code>ErrorManager</code>
  93    * of this <code>ConsoleHandler</code> will be informed, but the caller
  94    * of this method will not receive an exception.
  95    */
  96   public void close()
  97   {
  98     flush();
  99   }
 100
 101
 102   /**
 103    * Publishes a <code>LogRecord</code> to the console, provided the
 104    * record passes all tests for being loggable.
 105    *
 106    * <p>Most applications do not need to call this method directly.
 107    * Instead, they will use use a <code>Logger</code>, which will
 108    * create LogRecords and distribute them to registered handlers.
 109    *
 110    * <p>In case of an I/O failure, the <code>ErrorManager</code>
 111    * of this <code>SocketHandler</code> will be informed, but the caller
 112    * of this method will not receive an exception.
 113    *
 114    * <p>The GNU implementation of <code>ConsoleHandler.publish</code>
 115    * calls flush() for every request to publish a record, so
 116    * they appear immediately on the console.
 117    *
 118    * @param record the log event to be published.
 119    */
 120   public void publish(LogRecord record)
 121   {
 122     super.publish(record);
 123     flush();
 124   }
 125 }