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 * https://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
18 package org.apache.commons.logging.impl;
19
20 import java.io.Serializable;
21
22 import org.apache.commons.logging.Log;
23 import org.apache.log4j.Level;
24 import org.apache.log4j.Logger;
25 import org.apache.log4j.Priority;
26
27 /**
28 * Implements {@link Log} to map directly to a
29 * <strong>Logger</strong> for Apache Log4J version 1.2.
30 * <p>
31 * Initial configuration of the corresponding Logger instances should be done
32 * in the usual manner, as outlined in the Log4J documentation.
33 * <p>
34 * The reason this logger is distinct from the 1.3.0 logger is that in version 1.2
35 * of Log4J:
36 * <ul>
37 * <li>class Logger takes Priority parameters not Level parameters.</li>
38 * <li>class Level extends Priority</li>
39 * </ul>
40 * Log4j 1.3 is expected to change Level so it no longer extends Priority, which is
41 * a non-binary-compatible change. The class generated by compiling this code against
42 * Log4j 1.2 will therefore not run against Log4j 1.3.
43 *
44 * @deprecated Scheduled for removal since version 1.x of Log4j has reached end-of-life.
45 */
46 @Deprecated
47 public class Log4JLogger implements Log, Serializable {
48
49 /** Serializable version identifier. */
50 private static final long serialVersionUID = 5160705895411730424L;
51
52 /** The fully qualified name of the Log4JLogger class. */
53 private static final String FQCN = Log4JLogger.class.getName();
54
55 private static final Priority TRACE_LEVEL;
56
57 //
58 // Note that this must come after the static variable declarations
59 // otherwise initializer expressions associated with those variables
60 // will override any settings done here.
61 //
62 // Verify that Log4j is available, and that it is version 1.2.
63 // If an ExceptionInInitializerError is generated, then LogFactoryImpl
64 // will treat that as meaning that the appropriate underlying logging
65 // library is just not present - if discovery is in progress then
66 // discovery will continue.
67 static {
68 if (!Priority.class.isAssignableFrom(Level.class)) {
69 // nope, this is Log4j 1.3, so force an ExceptionInInitializerError
70 throw new InstantiationError("Log4J 1.2 not available");
71 }
72 // Releases of Log4j 1.2 >= 1.2.12 have Priority.TRACE available, earlier
73 // versions do not. If TRACE is not available, then we have to map
74 // calls to Log.trace(...) onto the DEBUG level.
75 Priority traceLevel;
76 try {
77 traceLevel = (Priority) Level.class.getDeclaredField("TRACE").get(null);
78 } catch (final Exception ex) {
79 // ok, trace not available
80 traceLevel = Level.DEBUG;
81 }
82 TRACE_LEVEL = traceLevel;
83 }
84
85 /** Log to this logger */
86 private transient volatile Logger logger;
87
88 /** Logger name */
89 private final String name;
90
91 /**
92 * Constructs a new instance.
93 */
94 public Log4JLogger() {
95 name = null;
96 }
97
98 /**
99 * For use with a Log4j factory.
100 *
101 * @param logger Logger.
102 */
103 public Log4JLogger(final Logger logger) {
104 if (logger == null) {
105 throw new IllegalArgumentException("Warning - null logger in constructor; possible Log4j misconfiguration.");
106 }
107 this.name = logger.getName();
108 this.logger = logger;
109 }
110
111 /**
112 * Base constructor.
113 *
114 * @param name name.
115 */
116 public Log4JLogger(final String name) {
117 this.name = name;
118 this.logger = getLogger();
119 }
120
121 /**
122 * Logs a message with {@code org.apache.log4j.Priority.DEBUG}.
123 *
124 * @param message to log
125 * @see org.apache.commons.logging.Log#debug(Object)
126 */
127 @Override
128 public void debug(final Object message) {
129 getLogger().log(FQCN, Level.DEBUG, message, null);
130 }
131
132 /**
133 * Logs a message with {@code org.apache.log4j.Priority.DEBUG}.
134 *
135 * @param message to log
136 * @param t log this cause
137 * @see org.apache.commons.logging.Log#debug(Object, Throwable)
138 */
139 @Override
140 public void debug(final Object message, final Throwable t) {
141 getLogger().log(FQCN, Level.DEBUG, message, t);
142 }
143
144 /**
145 * Logs a message with {@code org.apache.log4j.Priority.ERROR}.
146 *
147 * @param message to log
148 * @see org.apache.commons.logging.Log#error(Object)
149 */
150 @Override
151 public void error(final Object message) {
152 getLogger().log(FQCN, Level.ERROR, message, null);
153 }
154
155 /**
156 * Logs a message with {@code org.apache.log4j.Priority.ERROR}.
157 *
158 * @param message to log
159 * @param t log this cause
160 * @see org.apache.commons.logging.Log#error(Object, Throwable)
161 */
162 @Override
163 public void error(final Object message, final Throwable t) {
164 getLogger().log(FQCN, Level.ERROR, message, t);
165 }
166
167 /**
168 * Logs a message with {@code org.apache.log4j.Priority.FATAL}.
169 *
170 * @param message to log
171 * @see org.apache.commons.logging.Log#fatal(Object)
172 */
173 @Override
174 public void fatal(final Object message) {
175 getLogger().log(FQCN, Level.FATAL, message, null);
176 }
177
178 /**
179 * Logs a message with {@code org.apache.log4j.Priority.FATAL}.
180 *
181 * @param message to log
182 * @param t log this cause
183 * @see org.apache.commons.logging.Log#fatal(Object, Throwable)
184 */
185 @Override
186 public void fatal(final Object message, final Throwable t) {
187 getLogger().log(FQCN, Level.FATAL, message, t);
188 }
189
190 /**
191 * Gets the native Logger instance we are using.
192 *
193 * @return the native Logger instance we are using.
194 */
195 public Logger getLogger() {
196 Logger result = logger;
197 if (result == null) {
198 synchronized(this) {
199 result = logger;
200 if (result == null) {
201 logger = result = Logger.getLogger(name);
202 }
203 }
204 }
205 return result;
206 }
207
208 /**
209 * Logs a message with {@code org.apache.log4j.Priority.INFO}.
210 *
211 * @param message to log
212 * @see org.apache.commons.logging.Log#info(Object)
213 */
214 @Override
215 public void info(final Object message) {
216 getLogger().log(FQCN, Level.INFO, message, null);
217 }
218
219 /**
220 * Logs a message with {@code org.apache.log4j.Priority.INFO}.
221 *
222 * @param message to log
223 * @param t log this cause
224 * @see org.apache.commons.logging.Log#info(Object, Throwable)
225 */
226 @Override
227 public void info(final Object message, final Throwable t) {
228 getLogger().log(FQCN, Level.INFO, message, t);
229 }
230
231 /**
232 * Tests whether the Log4j Logger used is enabled for {@code DEBUG} priority.
233 */
234 @Override
235 public boolean isDebugEnabled() {
236 return getLogger().isDebugEnabled();
237 }
238
239 /**
240 * Tests whether the Log4j Logger used is enabled for {@code ERROR} priority.
241 */
242 @Override
243 public boolean isErrorEnabled() {
244 return getLogger().isEnabledFor(Level.ERROR);
245 }
246
247 /**
248 * Tests whether the Log4j Logger used is enabled for {@code FATAL} priority.
249 */
250 @Override
251 public boolean isFatalEnabled() {
252 return getLogger().isEnabledFor(Level.FATAL);
253 }
254
255 /**
256 * Tests whether the Log4j Logger used is enabled for {@code INFO} priority.
257 */
258 @Override
259 public boolean isInfoEnabled() {
260 return getLogger().isInfoEnabled();
261 }
262
263 /**
264 * Tests whether the Log4j Logger used is enabled for {@code TRACE} priority.
265 * When using a Log4j version that does not support the TRACE level, this call
266 * will report whether {@code DEBUG} is enabled or not.
267 */
268 @Override
269 public boolean isTraceEnabled() {
270 return getLogger().isEnabledFor(TRACE_LEVEL);
271 }
272
273 /**
274 * Tests whether the Log4j Logger used is enabled for {@code WARN} priority.
275 */
276 @Override
277 public boolean isWarnEnabled() {
278 return getLogger().isEnabledFor(Level.WARN);
279 }
280
281 /**
282 * Logs a message with {@code org.apache.log4j.Priority.TRACE}.
283 * When using a Log4j version that does not support the {@code TRACE}
284 * level, the message will be logged at the {@code DEBUG} level.
285 *
286 * @param message to log
287 * @see org.apache.commons.logging.Log#trace(Object)
288 */
289 @Override
290 public void trace(final Object message) {
291 getLogger().log(FQCN, TRACE_LEVEL, message, null);
292 }
293
294 /**
295 * Logs a message with {@code org.apache.log4j.Priority.TRACE}.
296 * When using a Log4j version that does not support the {@code TRACE}
297 * level, the message will be logged at the {@code DEBUG} level.
298 *
299 * @param message to log
300 * @param t log this cause
301 * @see org.apache.commons.logging.Log#trace(Object, Throwable)
302 */
303 @Override
304 public void trace(final Object message, final Throwable t) {
305 getLogger().log(FQCN, TRACE_LEVEL, message, t);
306 }
307
308 /**
309 * Logs a message with {@code org.apache.log4j.Priority.WARN}.
310 *
311 * @param message to log
312 * @see org.apache.commons.logging.Log#warn(Object)
313 */
314 @Override
315 public void warn(final Object message) {
316 getLogger().log(FQCN, Level.WARN, message, null);
317 }
318
319 /**
320 * Logs a message with {@code org.apache.log4j.Priority.WARN}.
321 *
322 * @param message to log
323 * @param t log this cause
324 * @see org.apache.commons.logging.Log#warn(Object, Throwable)
325 */
326 @Override
327 public void warn(final Object message, final Throwable t) {
328 getLogger().log(FQCN, Level.WARN, message, t);
329 }
330
331 }