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1
19 package org.apache.avalon.excalibur.logger.util;
20
21 import org.apache.avalon.framework.logger.Logger;
22 import org.apache.avalon.framework.logger.NullLogger;
23
24
39
40 public class LoggerSwitch
41 {
42 protected final static Logger SHARED_NULL = new NullLogger();
43
44 private final static class BooleanThreadLocal extends ThreadLocal 
45 {
46 public Object initialValue() { return Boolean.FALSE; }
47 public boolean value() { return ((Boolean )this.get()).booleanValue(); }
48 }
49
50 private static class SwitchingLogger implements Logger
51 {
52 Logger m_fallback;
53 Logger m_preferred;
54
55 BooleanThreadLocal m_recursionOnPreferred = new BooleanThreadLocal();
56 BooleanThreadLocal m_recursionOnFallback = new BooleanThreadLocal();
57
58 SwitchingLogger( final Logger fallback, final Logger preferred )
59 {
60 m_fallback = fallback != null ? fallback : SHARED_NULL;
61 m_preferred = preferred;
62 }
63
64 void setFallback( final Logger fallback )
65 {
66 m_fallback = fallback != null ? fallback : SHARED_NULL;
67 }
68
69 void setPreferred( final Logger preferred )
70 {
71 m_preferred = preferred;
72 }
73
74
80 private Logger getLogger()
81 {
82 if ( m_recursionOnFallback.value() )
83 {
84 throw new IllegalStateException ( "infinite recursion" );
85 }
86 else if ( m_recursionOnPreferred.value() || m_preferred == null )
87 {
88 m_recursionOnFallback.set( Boolean.TRUE );
89 return m_fallback;
90 }
91 else
92 {
93 m_recursionOnPreferred.set( Boolean.TRUE );
94 return m_preferred;
95 }
96 }
97
98 private Logger getLoggerLight()
99 {
100 return m_preferred != null ? m_preferred : m_fallback;
101 }
102
103 private void releaseLogger()
104 {
105 if ( m_recursionOnFallback.value() )
106 {
107 m_recursionOnFallback.set( Boolean.FALSE );
108 }
109 else if ( m_recursionOnPreferred.value() )
110 {
111 m_recursionOnPreferred.set( Boolean.FALSE );
112 }
113 else
114 {
115 throw new IllegalStateException ( "no recursion" );
116 }
117 }
118
119 public void debug( final String message )
120 {
121 final Logger logger = getLogger();
122 try
123 {
124 logger.debug( message );
125 }
126 finally
127 {
128 releaseLogger();
129 }
130 }
131
132 public void debug( final String message, final Throwable throwable )
133 {
134 final Logger logger = getLogger();
135 try
136 {
137 logger.debug( message, throwable );
138 }
139 finally
140 {
141 releaseLogger();
142 }
143 }
144
145
151 public boolean isDebugEnabled()
152 {
153 final Logger logger = getLoggerLight();
154 return logger.isDebugEnabled();
155 }
156
157
158 public void info( final String message )
159 {
160 final Logger logger = getLogger();
161 try
162 {
163 logger.info( message );
164 }
165 finally
166 {
167 releaseLogger();
168 }
169 }
170
171 public void info( final String message, final Throwable throwable )
172 {
173 final Logger logger = getLogger();
174 try
175 {
176 logger.info( message, throwable );
177 }
178 finally
179 {
180 releaseLogger();
181 }
182 }
183
184 public boolean isInfoEnabled()
185 {
186 final Logger logger = getLoggerLight();
187 return logger.isInfoEnabled();
188 }
189
190 public void warn( final String message )
191 {
192 final Logger logger = getLogger();
193 try
194 {
195 logger.warn( message );
196 }
197 finally
198 {
199 releaseLogger();
200 }
201 }
202
203 public void warn( final String message, final Throwable throwable )
204 {
205 final Logger logger = getLogger();
206 try
207 {
208 logger.warn( message, throwable );
209 }
210 finally
211 {
212 releaseLogger();
213 }
214 }
215
216 public boolean isWarnEnabled()
217 {
218 final Logger logger = getLoggerLight();
219 return logger.isWarnEnabled();
220 }
221
222 public void error( final String message )
223 {
224 final Logger logger = getLogger();
225 try
226 {
227 logger.error( message );
228 }
229 finally
230 {
231 releaseLogger();
232 }
233 }
234
235 public void error( final String message, final Throwable throwable )
236 {
237 final Logger logger = getLogger();
238 try
239 {
240 logger.error( message, throwable );
241 }
242 finally
243 {
244 releaseLogger();
245 }
246 }
247
248 public boolean isErrorEnabled()
249 {
250 final Logger logger = getLoggerLight();
251 return logger.isErrorEnabled();
252 }
253
254 public void fatalError( final String message )
255 {
256 final Logger logger = getLogger();
257 try
258 {
259 logger.fatalError( message );
260 }
261 finally
262 {
263 releaseLogger();
264 }
265 }
266
267 public void fatalError( final String message, final Throwable throwable )
268 {
269 final Logger logger = getLogger();
270 try
271 {
272 logger.fatalError( message, throwable );
273 }
274 finally
275 {
276 releaseLogger();
277 }
278 }
279
280 public boolean isFatalErrorEnabled()
281 {
282 final Logger logger = getLoggerLight();
283 return logger.isFatalErrorEnabled();
284 }
285
286 public Logger getChildLogger( final String name ) { return this; }
287
288 }
289
290 private SwitchingLogger m_switch;
291
292
298 public Logger get()
299 {
300 return m_switch;
301 }
302
303 public LoggerSwitch( final Logger fallback )
304 {
305 this( fallback, null );
306 }
307
308 public LoggerSwitch( final Logger fallback, final Logger preferred )
309 {
310 m_switch = new SwitchingLogger( fallback, preferred );
311 }
312
313 public void setFallback( final Logger fallback )
314 {
315 m_switch.setFallback( fallback );
316 }
317
318 public void setPreferred( final Logger preferred )
319 {
320 m_switch.setPreferred( preferred );
321 }
322 }
323 |
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