001 /* ConsoleHandler.java -- a class for publishing log messages to System.err
002 Copyright (C) 2002, 2004 Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
016 You should have received a copy of the GNU General Public License
017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038
039 package 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 */
072 public 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 }