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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements. See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache license, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License. You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the license for the specific language governing permissions and
15   * limitations under the license.
16   */
17  package org.apache.log4j;
18  
19  import java.io.IOException;
20  import java.io.ObjectInputStream;
21  import java.io.ObjectOutputStream;
22  import java.io.ObjectStreamException;
23  import java.io.Serializable;
24  
25  /**
26   * Defines the minimum set of levels recognized by the system, that is
27   * <code>OFF</code>, <code>FATAL</code>, <code>ERROR</code>,
28   * <code>WARN</code>, <code>INFO</code, <code>DEBUG</code>
29   * and
30   * <code>ALL</code>.
31   * <p/>
32   * <p>The <code>Level</code> class may be subclassed to define a larger
33   * level set.
34   */
35  public class Level extends Priority implements Serializable {
36  
37      /**
38       * TRACE level integer value.
39       *
40       * @since 1.2.12
41       */
42      public static final int TRACE_INT = 5000;
43  
44      /**
45       * The <code>OFF</code> has the highest possible rank and is
46       * intended to turn off logging.
47       */
48      public static final Level OFF = new Level(OFF_INT, "OFF", 0);
49  
50      /**
51       * The <code>FATAL</code> level designates very severe error
52       * events that will presumably lead the application to abort.
53       */
54      public static final Level FATAL = new Level(FATAL_INT, "FATAL", 0);
55  
56      /**
57       * The <code>ERROR</code> level designates error events that
58       * might still allow the application to continue running.
59       */
60      public static final Level ERROR = new Level(ERROR_INT, "ERROR", 3);
61  
62      /**
63       * The <code>WARN</code> level designates potentially harmful situations.
64       */
65      public static final Level WARN = new Level(WARN_INT, "WARN", 4);
66  
67      /**
68       * The <code>INFO</code> level designates informational messages
69       * that highlight the progress of the application at coarse-grained
70       * level.
71       */
72      public static final Level INFO = new Level(INFO_INT, "INFO", 6);
73  
74      /**
75       * The <code>DEBUG</code> Level designates fine-grained
76       * informational events that are most useful to debug an
77       * application.
78       */
79      public static final Level DEBUG = new Level(DEBUG_INT, "DEBUG", 7);
80  
81      /**
82       * The <code>TRACE</code> Level designates finer-grained
83       * informational events than the <code>DEBUG</code> level.
84       */
85      public static final Level TRACE = new Level(TRACE_INT, "TRACE", 7);
86  
87      /**
88       * The <code>ALL</code> has the lowest possible rank and is intended to
89       * turn on all logging.
90       */
91      public static final Level ALL = new Level(ALL_INT, "ALL", 7);
92  
93      /**
94       * Serialization version id.
95       */
96      private static final long serialVersionUID = 3491141966387921974L;
97  
98      /**
99       * Instantiate a Level object.
100      *
101      * @param level            The logging level.
102      * @param levelStr         The level name.
103      * @param syslogEquivalent The matching syslog level.
104      */
105     protected Level(final int level, final String levelStr, final 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      * @param sArg The level name.
115      * @return The Level.
116      */
117     public static Level toLevel(final String sArg) {
118         return toLevel(sArg, Level.DEBUG);
119     }
120 
121     /**
122      * Convert an integer passed as argument to a level. If the
123      * conversion fails, then this method returns {@link #DEBUG}.
124      *
125      * @param val The integer value of the Level.
126      * @return The Level.
127      */
128     public static Level toLevel(final int val) {
129         return toLevel(val, Level.DEBUG);
130     }
131 
132     /**
133      * Convert an integer passed as argument to a level. If the
134      * conversion fails, then this method returns the specified default.
135      *
136      * @param val          The integer value of the Level.
137      * @param defaultLevel the default level if the integer doesn't match.
138      * @return The matching Level.
139      */
140     public static Level toLevel(final int val, final Level defaultLevel) {
141         switch (val) {
142             case ALL_INT:
143                 return ALL;
144             case DEBUG_INT:
145                 return Level.DEBUG;
146             case INFO_INT:
147                 return Level.INFO;
148             case WARN_INT:
149                 return Level.WARN;
150             case ERROR_INT:
151                 return Level.ERROR;
152             case FATAL_INT:
153                 return Level.FATAL;
154             case OFF_INT:
155                 return OFF;
156             case TRACE_INT:
157                 return Level.TRACE;
158             default:
159                 return defaultLevel;
160         }
161     }
162 
163     /**
164      * Convert the string passed as argument to a level. If the
165      * conversion fails, then this method returns the value of
166      * <code>defaultLevel</code>.
167      * @param sArg The name of the Level.
168      * @param defaultLevel The default Level to use.
169      * @return the matching Level.
170      */
171     public static Level toLevel(final String sArg, final Level defaultLevel) {
172         if (sArg == null) {
173             return defaultLevel;
174         }
175 
176         final String s = sArg.toUpperCase();
177 
178         if (s.equals("ALL")) {
179             return Level.ALL;
180         }
181         if (s.equals("DEBUG")) {
182             return Level.DEBUG;
183         }
184         if (s.equals("INFO")) {
185             return Level.INFO;
186         }
187         if (s.equals("WARN")) {
188             return Level.WARN;
189         }
190         if (s.equals("ERROR")) {
191             return Level.ERROR;
192         }
193         if (s.equals("FATAL")) {
194             return Level.FATAL;
195         }
196         if (s.equals("OFF")) {
197             return Level.OFF;
198         }
199         if (s.equals("TRACE")) {
200             return Level.TRACE;
201         }
202         //
203         //   For Turkish i problem, see bug 40937
204         //
205         if (s.equals("\u0130NFO")) {
206             return Level.INFO;
207         }
208         return defaultLevel;
209     }
210 
211     /**
212      * Custom deserialization of Level.
213      *
214      * @param s serialization stream.
215      * @throws IOException            if IO exception.
216      * @throws ClassNotFoundException if class not found.
217      */
218     private void readObject(final ObjectInputStream s) throws IOException, ClassNotFoundException {
219         s.defaultReadObject();
220         level = s.readInt();
221         syslogEquivalent = s.readInt();
222         levelStr = s.readUTF();
223         if (levelStr == null) {
224             levelStr = "";
225         }
226     }
227 
228     /**
229      * Serialize level.
230      *
231      * @param s serialization stream.
232      * @throws IOException if exception during serialization.
233      */
234     private void writeObject(final ObjectOutputStream s) throws IOException {
235         s.defaultWriteObject();
236         s.writeInt(level);
237         s.writeInt(syslogEquivalent);
238         s.writeUTF(levelStr);
239     }
240 
241     /**
242      * Resolved deserialized level to one of the stock instances.
243      * May be overridden in classes derived from Level.
244      *
245      * @return resolved object.
246      * @throws ObjectStreamException if exception during resolution.
247      */
248     protected Object readResolve() throws ObjectStreamException {
249         //
250         //  if the deserialized object is exactly an instance of Level
251         //
252         if (getClass() == Level.class) {
253             return toLevel(level);
254         }
255         //
256         //   extension of Level can't substitute stock item
257         //
258         return this;
259     }
260 
261 }
262