001/* ConsoleHandler.java -- a class for publishing log messages to System.err
002   Copyright (C) 2002, 2004 Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package java.util.logging;
040
041/**
042 * A <code>ConsoleHandler</code> publishes log records to
043 * <code>System.err</code>.
044 *
045 * <p><strong>Configuration:</strong> Values of the subsequent
046 * <code>LogManager</code> properties are taken into consideration
047 * when a <code>ConsoleHandler</code> is initialized.
048 * If a property is not defined, or if it has an invalid
049 * value, a default is taken without an exception being thrown.
050 *
051 * <ul>
052 *
053 * <li><code>java.util.logging.ConsoleHandler.level</code> - specifies
054 *     the initial severity level threshold. Default value:
055 *     <code>Level.INFO</code>.</li>
056 *
057 * <li><code>java.util.logging.ConsoleHandler.filter</code> - specifies
058 *     the name of a Filter class. Default value: No Filter.</li>
059 *
060 * <li><code>java.util.logging.ConsoleHandler.formatter</code> - specifies
061 *     the name of a Formatter class. Default value:
062 *     <code>java.util.logging.SimpleFormatter</code>.</li>
063 *
064 * <li><code>java.util.logging.ConsoleHandler.encoding</code> - specifies
065 *     the name of the character encoding. Default value:
066 *     the default platform encoding.</li>
067 *
068 * </ul>
069 *
070 * @author Sascha Brawer (brawer@acm.org)
071 */
072public class ConsoleHandler
073  extends StreamHandler
074{
075  /**
076   * Constructs a <code>StreamHandler</code> that publishes
077   * log records to <code>System.err</code>.  The initial
078   * configuration is determined by the <code>LogManager</code>
079   * properties described above.
080   */
081  public ConsoleHandler()
082  {
083    super(System.err, "java.util.logging.ConsoleHandler", Level.INFO,
084         /* formatter */ null, SimpleFormatter.class);
085  }
086
087
088  /**
089   * Forces any data that may have been buffered to the underlying
090   * output device, but does <i>not</i> close <code>System.err</code>.
091   *
092   * <p>In case of an I/O failure, the <code>ErrorManager</code>
093   * of this <code>ConsoleHandler</code> will be informed, but the caller
094   * of this method will not receive an exception.
095   */
096  public void close()
097  {
098    flush();
099  }
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}