1 /* 2 * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 27 package java.util.logging; 28 29 /** 30 * This <tt>Handler</tt> publishes log records to <tt>System.err</tt>. 31 * By default the <tt>SimpleFormatter</tt> is used to generate brief summaries. 32 * <p> 33 * <b>Configuration:</b> 34 * By default each <tt>ConsoleHandler</tt> is initialized using the following 35 * <tt>LogManager</tt> configuration properties where {@code <handler-name>} 36 * refers to the fully-qualified class name of the handler. 37 * If properties are not defined 38 * (or have invalid values) then the specified default values are used. 39 * <ul> 40 * <li> <handler-name>.level 41 * specifies the default level for the <tt>Handler</tt> 42 * (defaults to <tt>Level.INFO</tt>). </li> 43 * <li> <handler-name>.filter 44 * specifies the name of a <tt>Filter</tt> class to use 45 * (defaults to no <tt>Filter</tt>). </li> 46 * <li> <handler-name>.formatter 47 * specifies the name of a <tt>Formatter</tt> class to use 48 * (defaults to <tt>java.util.logging.SimpleFormatter</tt>). </li> 49 * <li> <handler-name>.encoding 50 * the name of the character set encoding to use (defaults to 51 * the default platform encoding). </li> 52 * </ul> 53 * <p> 54 * For example, the properties for {@code ConsoleHandler} would be: 55 * <ul> 56 * <li> java.util.logging.ConsoleHandler.level=INFO </li> 57 * <li> java.util.logging.ConsoleHandler.formatter=java.util.logging.SimpleFormatter </li> 58 * </ul> 59 * <p> 60 * For a custom handler, e.g. com.foo.MyHandler, the properties would be: 61 * <ul> 62 * <li> com.foo.MyHandler.level=INFO </li> 63 * <li> com.foo.MyHandler.formatter=java.util.logging.SimpleFormatter </li> 64 * </ul> 65 * <p> 66 * @since 1.4 67 */ 68 public class ConsoleHandler extends StreamHandler { 69 // Private method to configure a ConsoleHandler from LogManager 70 // properties and/or default values as specified in the class 71 // javadoc. configure()72 private void configure() { 73 LogManager manager = LogManager.getLogManager(); 74 String cname = getClass().getName(); 75 76 setLevel(manager.getLevelProperty(cname +".level", Level.INFO)); 77 setFilter(manager.getFilterProperty(cname +".filter", null)); 78 setFormatter(manager.getFormatterProperty(cname +".formatter", new SimpleFormatter())); 79 try { 80 setEncoding(manager.getStringProperty(cname +".encoding", null)); 81 } catch (Exception ex) { 82 try { 83 setEncoding(null); 84 } catch (Exception ex2) { 85 // doing a setEncoding with null should always work. 86 // assert false; 87 } 88 } 89 } 90 91 /** 92 * Create a <tt>ConsoleHandler</tt> for <tt>System.err</tt>. 93 * <p> 94 * The <tt>ConsoleHandler</tt> is configured based on 95 * <tt>LogManager</tt> properties (or their default values). 96 * 97 */ ConsoleHandler()98 public ConsoleHandler() { 99 sealed = false; 100 configure(); 101 setOutputStream(System.err); 102 sealed = true; 103 } 104 105 /** 106 * Publish a <tt>LogRecord</tt>. 107 * <p> 108 * The logging request was made initially to a <tt>Logger</tt> object, 109 * which initialized the <tt>LogRecord</tt> and forwarded it here. 110 * <p> 111 * @param record description of the log event. A null record is 112 * silently ignored and is not published 113 */ 114 @Override publish(LogRecord record)115 public void publish(LogRecord record) { 116 super.publish(record); 117 flush(); 118 } 119 120 /** 121 * Override <tt>StreamHandler.close</tt> to do a flush but not 122 * to close the output stream. That is, we do <b>not</b> 123 * close <tt>System.err</tt>. 124 */ 125 @Override close()126 public void close() { 127 flush(); 128 } 129 } 130