1 /*
2 * Copyright 2001-2004 The Apache Software Foundation.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 // Contributors: Kitching Simon <Simon.Kitching@orange.ch>
18 // Nicholas Wolff
19
20 package org.apache.log4j;
21 import java.io.IOException;
22 import java.io.ObjectInputStream;
23 import java.io.ObjectOutputStream;
24 import java.io.ObjectStreamException;
25 import java.io.Serializable;
26
27 /**
28 Defines the minimum set of levels recognized by the system, that is
29 <code>OFF</code>, <code>FATAL</code>, <code>ERROR</code>,
30 <code>WARN</code>, <code>INFO</code>, <code>DEBUG</code> and
31 <code>ALL</code>.
32
33 <p>The <code>Level</code> class may be subclassed to define a larger
34 level set.
35
36 @author Ceki Gülcü
37
38 */
39 public class Level extends Priority implements Serializable {
40
41 /**
42 * TRACE level integer value.
43 * @since 1.2.12
44 */
45 public static final int TRACE_INT = 5000;
46
47 // match jboss' xlevel
48 public static final int X_TRACE_INT = DEBUG_INT - 100;
49
50 /**
51 The <code>OFF</code> has the highest possible rank and is
52 intended to turn off logging. */
53 final static public Level OFF = new Level(OFF_INT, "OFF", 0);
54
55 /**
56 The <code>FATAL</code> level designates very severe error
57 events that will presumably lead the application to abort.
58 */
59 final static public Level FATAL = new Level(FATAL_INT, "FATAL", 0);
60
61 /**
62 The <code>ERROR</code> level designates error events that
63 might still allow the application to continue running. */
64 final static public Level ERROR = new Level(ERROR_INT, "ERROR", 3);
65
66 /**
67 The <code>WARN</code> level designates potentially harmful situations.
68 */
69 final static public Level WARN = new Level(WARN_INT, "WARN", 4);
70
71 /**
72 The <code>INFO</code> level designates informational messages
73 that highlight the progress of the application at coarse-grained
74 level. */
75 final static public Level INFO = new Level(INFO_INT, "INFO", 6);
76
77 /**
78 The <code>DEBUG</code> Level designates fine-grained
79 informational events that are most useful to debug an
80 application. */
81 final static public Level DEBUG = new Level(DEBUG_INT, "DEBUG", 7);
82
83 /**
84 * The <code>TRACE</code> Level designates finer-grained
85 * informational events than the <code>DEBUG</code level.
86 * @since 1.2.12
87 */
88 public static final Level TRACE = new Level(TRACE_INT, "TRACE", 7);
89
90
91 /**
92 The <code>ALL</code> has the lowest possible rank and is intended to
93 turn on all logging. */
94 final static public Level ALL = new Level(ALL_INT, "ALL", 7);
95
96 /**
97 * Serialization version id.
98 */
99 static final long serialVersionUID = 3491141966387921974L;
100
101 /**
102 Instantiate a Level object.
103 */
104 protected
105 Level(int level, String levelStr, int syslogEquivalent) {
106 super(level, levelStr, syslogEquivalent);
107 }
108
109
110 /**
111 Convert the string passed as argument to a level. If the
112 conversion fails, then this method returns {@link #DEBUG}.
113 */
114 public
115 static
116 Level toLevel(String sArg) {
117 return (Level) toLevel(sArg, Level.DEBUG);
118 }
119
120 /**
121 Convert an integer passed as argument to a level. If the
122 conversion fails, then this method returns {@link #DEBUG}.
123
124 */
125 public
126 static
127 Level toLevel(int val) {
128 return (Level) toLevel(val, Level.DEBUG);
129 }
130
131 /**
132 Convert an integer passed as argument to a level. If the
133 conversion fails, then this method returns the specified default.
134 */
135 public
136 static
137 Level toLevel(int val, Level defaultLevel) {
138 switch(val) {
139 case ALL_INT: return ALL;
140 case DEBUG_INT: return Level.DEBUG;
141 case INFO_INT: return Level.INFO;
142 case WARN_INT: return Level.WARN;
143 case ERROR_INT: return Level.ERROR;
144 case FATAL_INT: return Level.FATAL;
145 case OFF_INT: return OFF;
146 case TRACE_INT: return Level.TRACE;
147 default: return defaultLevel;
148 }
149 }
150
151 /**
152 Convert the string passed as argument to a level. If the
153 conversion fails, then this method returns the value of
154 <code>defaultLevel</code>.
155 */
156 public
157 static
158 Level toLevel(String sArg, Level defaultLevel) {
159 if(sArg == null)
160 return defaultLevel;
161
162 String s = sArg.toUpperCase();
163
164 if(s.equals("ALL")) return Level.ALL;
165 if(s.equals("DEBUG")) return Level.DEBUG;
166 if(s.equals("INFO")) return Level.INFO;
167 if(s.equals("WARN")) return Level.WARN;
168 if(s.equals("ERROR")) return Level.ERROR;
169 if(s.equals("FATAL")) return Level.FATAL;
170 if(s.equals("OFF")) return Level.OFF;
171 if(s.equals("TRACE")) return Level.TRACE;
172 return defaultLevel;
173 }
174
175 /**
176 * Custom deserialization of Level.
177 * @param s serialization stream.
178 * @throws IOException if IO exception.
179 * @throws ClassNotFoundException if class not found.
180 */
181 private void readObject(final ObjectInputStream s) throws IOException, ClassNotFoundException {
182 s.defaultReadObject();
183 level = s.readInt();
184 syslogEquivalent = s.readInt();
185 levelStr = s.readUTF();
186 if (levelStr == null) {
187 levelStr = "";
188 }
189 }
190
191 /**
192 * Serialize level.
193 * @param s serialization stream.
194 * @throws IOException if exception during serialization.
195 */
196 private void writeObject(final ObjectOutputStream s) throws IOException {
197 s.defaultWriteObject();
198 s.writeInt(level);
199 s.writeInt(syslogEquivalent);
200 s.writeUTF(levelStr);
201 }
202
203 /**
204 * Resolved deserialized level to one of the stock instances.
205 * May be overriden in classes derived from Level.
206 * @return resolved object.
207 * @throws ObjectStreamException if exception during resolution.
208 */
209 private Object readResolve() throws ObjectStreamException {
210 //
211 // if the deserizalized object is exactly an instance of Level
212 //
213 if (getClass() == Level.class) {
214 return toLevel(level);
215 }
216 //
217 // extension of Level can't substitute stock item
218 //
219 return this;
220 }
221 }