001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache license, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the license for the specific language governing permissions and 015 * limitations under the license. 016 */ 017 package org.apache.logging.log4j; 018 019 import java.io.Serializable; 020 import java.util.Collection; 021 import java.util.Locale; 022 import java.util.concurrent.ConcurrentHashMap; 023 import java.util.concurrent.ConcurrentMap; 024 025 import org.apache.logging.log4j.spi.StandardLevel; 026 027 /** 028 * Levels used for identifying the severity of an event. Levels are organized from most specific to least: 029 * <ul> 030 * <li>{@link #OFF} (most specific, no logging)</li> 031 * <li>{@link #FATAL} (most specific, little data)</li> 032 * <li>{@link #ERROR}</li> 033 * <li>{@link #WARN}</li> 034 * <li>{@link #INFO}</li> 035 * <li>{@link #DEBUG}</li> 036 * <li>{@link #TRACE} (least specific, a lot of data)</li> 037 * <li>{@link #ALL} (least specific, all data)</li> 038 * </ul> 039 * 040 * Typically, configuring a level in a filter or on a logger will cause logging events of that level and those 041 * that are more specific to pass through the filter. 042 * A special level, {@link #ALL}, is guaranteed to capture all levels when used in logging configurations. 043 */ 044 public final class Level implements Comparable<Level>, Serializable { 045 046 private static final long serialVersionUID = 1581082L; 047 private static final ConcurrentMap<String, Level> levels = new ConcurrentHashMap<String, Level>(); 048 049 /** 050 * No events will be logged. 051 */ 052 public static final Level OFF; 053 054 /** 055 * A severe error that will prevent the application from continuing. 056 */ 057 public static final Level FATAL; 058 059 /** 060 * An error in the application, possibly recoverable. 061 */ 062 public static final Level ERROR; 063 064 /** 065 * An event that might possible lead to an error. 066 */ 067 public static final Level WARN; 068 069 /** 070 * An event for informational purposes. 071 */ 072 public static final Level INFO; 073 074 /** 075 * A general debugging event. 076 */ 077 public static final Level DEBUG; 078 079 /** 080 * A fine-grained debug message, typically capturing the flow through the application. 081 */ 082 public static final Level TRACE; 083 084 /** 085 * All events should be logged. 086 */ 087 public static final Level ALL; 088 089 static { 090 OFF = new Level("OFF", StandardLevel.OFF.intLevel()); 091 FATAL = new Level("FATAL", StandardLevel.FATAL.intLevel()); 092 ERROR = new Level("ERROR", StandardLevel.ERROR.intLevel()); 093 WARN = new Level("WARN", StandardLevel.WARN.intLevel()); 094 INFO = new Level("INFO", StandardLevel.INFO.intLevel()); 095 DEBUG = new Level("DEBUG", StandardLevel.DEBUG.intLevel()); 096 TRACE = new Level("TRACE", StandardLevel.TRACE.intLevel()); 097 ALL = new Level("ALL", StandardLevel.ALL.intLevel()); 098 } 099 100 private final String name; 101 private final int intLevel; 102 private final StandardLevel standardLevel; 103 104 private Level(final String name, final int intLevel) { 105 if (name == null || name.isEmpty()) { 106 throw new IllegalArgumentException("Illegal null Level constant"); 107 } 108 if (intLevel < 0) { 109 throw new IllegalArgumentException("Illegal Level int less than zero."); 110 } 111 this.name = name; 112 this.intLevel = intLevel; 113 this.standardLevel = StandardLevel.getStandardLevel(intLevel); 114 if (levels.putIfAbsent(name, this) != null) { 115 throw new IllegalStateException("Level " + name + " has already been defined."); 116 } 117 } 118 119 /** 120 * Gets the integral value of this Level. 121 * 122 * @return the value of this Level. 123 */ 124 public int intLevel() { 125 return this.intLevel; 126 } 127 128 /** 129 * Gets the standard Level values as an enum. 130 * 131 * @return an enum of the standard Levels. 132 */ 133 public StandardLevel getStandardLevel() { 134 return standardLevel; 135 } 136 137 /** 138 * Compares this level against the level passed as an argument and returns true if this level is the same or is less 139 * specific.T 140 * 141 * @param level 142 * The level to test. 143 * @return True if this level Level is less specific or the same as the given Level. 144 */ 145 public boolean isLessSpecificThan(final Level level) { 146 return this.intLevel >= level.intLevel; 147 } 148 149 /** 150 * Compares this level against the level passed as an argument and returns true if this level is the same or is more 151 * specific. 152 * 153 * @param level 154 * The level to test. 155 * @return True if this level Level is more specific or the same as the given Level. 156 */ 157 public boolean isMoreSpecificThan(final Level level) { 158 return this.intLevel <= level.intLevel; 159 } 160 161 @Override 162 @SuppressWarnings("CloneDoesntCallSuperClone") 163 public Level clone() throws CloneNotSupportedException { 164 throw new CloneNotSupportedException(); 165 } 166 167 @Override 168 public int compareTo(final Level other) { 169 return intLevel < other.intLevel ? -1 : (intLevel > other.intLevel ? 1 : 0); 170 } 171 172 @Override 173 public boolean equals(final Object other) { 174 return other instanceof Level && other == this; 175 } 176 177 public Class<Level> getDeclaringClass() { 178 return Level.class; 179 } 180 181 @Override 182 public int hashCode() { 183 return this.name.hashCode(); 184 } 185 186 /** 187 * Gets the symbolic name of this Level. Equivalent to calling {@link #toString()}. 188 * 189 * @return the name of this Level. 190 */ 191 public String name() { 192 return this.name; 193 } 194 195 @Override 196 public String toString() { 197 return this.name; 198 } 199 200 /** 201 * Retrieves an existing Level or creates on if it didn't previously exist. 202 * @param name The name of the level. 203 * @param intValue The integer value for the Level. If the level was previously created this value is ignored. 204 * @return The Level. 205 * @throws java.lang.IllegalArgumentException if the name is null or intValue is less than zero. 206 */ 207 public static Level forName(final String name, final int intValue) { 208 final Level level = levels.get(name); 209 if (level != null) { 210 return level; 211 } 212 try { 213 return new Level(name, intValue); 214 } catch (final IllegalStateException ex) { 215 // The level was added by something else so just return that one. 216 return levels.get(name); 217 } 218 } 219 220 /** 221 * Return the Level associated with the name or null if the Level cannot be found. 222 * @param name The name of the Level. 223 * @return The Level or null. 224 */ 225 public static Level getLevel(final String name) { 226 return levels.get(name); 227 } 228 229 /** 230 * Converts the string passed as argument to a level. If the 231 * conversion fails, then this method returns {@link #DEBUG}. 232 * 233 * @param sArg The name of the desired Level. 234 * @return The Level associated with the String. 235 */ 236 public static Level toLevel(final String sArg) { 237 return toLevel(sArg, Level.DEBUG); 238 } 239 240 /** 241 * Converts the string passed as argument to a level. If the 242 * conversion fails, then this method returns the value of 243 * <code>defaultLevel</code>. 244 * 245 * @param name The name of the desired Level. 246 * @param defaultLevel The Level to use if the String is invalid. 247 * @return The Level associated with the String. 248 */ 249 public static Level toLevel(final String name, final Level defaultLevel) { 250 if (name == null) { 251 return defaultLevel; 252 } 253 final Level level = levels.get(name.toUpperCase(Locale.ENGLISH)); 254 return level == null ? defaultLevel : level; 255 } 256 257 /** 258 * Return an array of all the Levels that have been registered. 259 * @return An array of Levels. 260 */ 261 public static Level[] values() { 262 final Collection<Level> values = Level.levels.values(); 263 return values.toArray(new Level[values.size()]); 264 } 265 266 /** 267 * Return the Level associated with the name. 268 * @param name The name of the Level to return. 269 * @return The Level. 270 * @throws java.lang.NullPointerException if the Level name is {@code null}. 271 * @throws java.lang.IllegalArgumentException if the Level name is not registered. 272 */ 273 public static Level valueOf(final String name) { 274 if (name == null) { 275 throw new NullPointerException("No level name given."); 276 } 277 final String levelName = name.toUpperCase(); 278 if (levels.containsKey(levelName)) { 279 return levels.get(levelName); 280 } 281 throw new IllegalArgumentException("Unknown level constant [" + levelName + "]."); 282 } 283 284 /** 285 * Returns the enum constant of the specified enum type with the specified name. The name must match exactly an 286 * identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.) 287 * 288 * @param enumType the {@code Class} object of the enum type from which to return a constant 289 * @param name the name of the constant to return 290 * @param <T> The enum type whose constant is to be returned 291 * @return the enum constant of the specified enum type with the specified name 292 * @throws java.lang.IllegalArgumentException if the specified enum type has no constant with the specified name, 293 * or the specified class object does not represent an enum type 294 * @throws java.lang.NullPointerException if {@code enumType} or {@code name} are {@code null} 295 * @see java.lang.Enum#valueOf(Class, String) 296 */ 297 public static <T extends Enum<T>> T valueOf(final Class<T> enumType, final String name) { 298 return Enum.valueOf(enumType, name); 299 } 300 301 // for deserialization 302 protected Object readResolve() { 303 return Level.valueOf(this.name); 304 } 305 } 306