1 /* 2 * Copyright (c) 2000, 2020, 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 import java.io.*; 30 import java.time.ZoneId; 31 import java.time.ZonedDateTime; 32 import jdk.internal.logger.SurrogateLogger; 33 34 /** 35 * Print a brief summary of the {@code LogRecord} in a human readable 36 * format. The summary will typically be 1 or 2 lines. 37 * 38 * <p> 39 * <a id="formatting"> 40 * <b>Configuration:</b></a> 41 * The {@code SimpleFormatter} is initialized with the format string 42 * specified in the {@systemProperty java.util.logging.SimpleFormatter.format} 43 * property to {@linkplain #format(LogRecord) format} the log messages. 44 * This property can be defined 45 * in the {@linkplain LogManager#getProperty logging properties} 46 * configuration file 47 * or as a system property. If this property is set in both 48 * the logging properties and system properties, 49 * the format string specified in the system property will be used. 50 * If this property is not defined or the given format string 51 * is {@linkplain java.util.IllegalFormatException illegal}, 52 * the default format is implementation-specific. 53 * 54 * @since 1.4 55 * @see java.util.Formatter 56 */ 57 58 public class SimpleFormatter extends Formatter { 59 60 // format string for printing the log record 61 static String getLoggingProperty(String name) { 62 return LogManager.getLogManager().getProperty(name); 63 } 64 65 private final String format = 66 SurrogateLogger.getSimpleFormat(SimpleFormatter::getLoggingProperty); 67 68 /** 69 * Format the given LogRecord. 70 * <p> 71 * The formatting can be customized by specifying the format string 72 * in the <a href="#formatting"> 73 * {@code java.util.logging.SimpleFormatter.format}</a> property. 74 * The given {@code LogRecord} will be formatted as if by calling: 75 * <pre> 76 * {@link String#format String.format}(format, date, source, logger, level, message, thrown); 77 * </pre> 78 * where the arguments are:<br> 79 * <ol> 80 * <li>{@code format} - the {@link java.util.Formatter 81 * java.util.Formatter} format string specified in the 82 * {@code java.util.logging.SimpleFormatter.format} property 83 * or the default format.</li> 84 * <li>{@code date} - a {@link ZonedDateTime} object representing 85 * {@linkplain LogRecord#getInstant() event time} of the log record 86 * in the {@link ZoneId#systemDefault()} system time zone.</li> 87 * <li>{@code source} - a string representing the caller, if available; 88 * otherwise, the logger's name.</li> 89 * <li>{@code logger} - the logger's name.</li> 90 * <li>{@code level} - the {@linkplain Level#getLocalizedName 91 * log level}.</li> 92 * <li>{@code message} - the formatted log message 93 * returned from the {@link Formatter#formatMessage(LogRecord)} 94 * method. It uses {@link java.text.MessageFormat java.text} 95 * formatting and does not use the {@code java.util.Formatter 96 * format} argument.</li> 97 * <li>{@code thrown} - a string representing 98 * the {@linkplain LogRecord#getThrown throwable} 99 * associated with the log record and its backtrace 100 * beginning with a newline character, if any; 101 * otherwise, an empty string.</li> 102 * </ol> 103 * 104 * <p>Some example formats:<br> 105 * <ul> 106 * <li> {@code java.util.logging.SimpleFormatter.format="%4$s: %5$s [%1$tc]%n"} 107 * <p>This prints 1 line with the log level ({@code 4$}), 108 * the log message ({@code 5$}) and the timestamp ({@code 1$}) in 109 * a square bracket. 110 * <pre> 111 * WARNING: warning message [Tue Mar 22 13:11:31 PDT 2011] 112 * </pre></li> 113 * <li> {@code java.util.logging.SimpleFormatter.format="%1$tc %2$s%n%4$s: %5$s%6$s%n"} 114 * <p>This prints 2 lines where the first line includes 115 * the timestamp ({@code 1$}) and the source ({@code 2$}); 116 * the second line includes the log level ({@code 4$}) and 117 * the log message ({@code 5$}) followed by the throwable 118 * and its backtrace ({@code 6$}), if any: 119 * <pre> 120 * Tue Mar 22 13:11:31 PDT 2011 MyClass fatal 121 * SEVERE: several message with an exception 122 * java.lang.IllegalArgumentException: invalid argument 123 * at MyClass.mash(MyClass.java:9) 124 * at MyClass.crunch(MyClass.java:6) 125 * at MyClass.main(MyClass.java:3) 126 * </pre></li> 127 * <li> {@code java.util.logging.SimpleFormatter.format="%1$tb %1$td, %1$tY %1$tl:%1$tM:%1$tS %1$Tp %2$s%n%4$s: %5$s%n"} 128 * <p>This prints 2 lines similar to the example above 129 * with a different date/time formatting and does not print 130 * the throwable and its backtrace: 131 * <pre> 132 * Mar 22, 2011 1:11:31 PM MyClass fatal 133 * SEVERE: several message with an exception 134 * </pre></li> 135 * <li> {@code java.util.logging.SimpleFormatter.format="%1$tb %1$td, %1$tY %1$tl:%1$tM:%1$tS.%1$tN %1$Tp %2$s%n%4$s: %5$s%6$s%n"} 136 * <p>Since JDK 9, {@code java.util.logging} uses {@link 137 * java.time.Clock#systemUTC() java.time} to create more precise time 138 * stamps. 139 * The format above can be used to add a {@code .%1$tN} to the 140 * date/time formatting so that nanoseconds will also be printed: 141 * <pre> 142 * Feb 06, 2015 5:33:10.279216000 PM example.Main main 143 * INFO: This is a test 144 * </pre></li> 145 * </ul> 146 * <p>This method can also be overridden in a subclass. 147 * It is recommended to use the {@link Formatter#formatMessage} 148 * convenience method to localize and format the message field. 149 * 150 * @param record the log record to be formatted. 151 * @return a formatted log record 152 */ 153 @Override 154 public String format(LogRecord record) { 155 ZonedDateTime zdt = ZonedDateTime.ofInstant( 156 record.getInstant(), ZoneId.systemDefault()); 157 String source; 158 if (record.getSourceClassName() != null) { 159 source = record.getSourceClassName(); 160 if (record.getSourceMethodName() != null) { 161 source += " " + record.getSourceMethodName(); 162 } 163 } else { 164 source = record.getLoggerName(); 165 } 166 String message = formatMessage(record); 167 String throwable = ""; 168 if (record.getThrown() != null) { 169 StringWriter sw = new StringWriter(); 170 PrintWriter pw = new PrintWriter(sw); 171 pw.println(); 172 record.getThrown().printStackTrace(pw); 173 pw.close(); 174 throwable = sw.toString(); 175 } 176 return String.format(format, 177 zdt, 178 source, 179 record.getLoggerName(), 180 record.getLevel().getLocalizedLevelName(), 181 message, 182 throwable); 183 } 184 }