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21
22 package org.armedbear.j;
23
24 import java.io.IOException  ;
25 import java.io.PrintWriter ;
26 import java.io.StringWriter ;
27 import java.text.SimpleDateFormat ;
28 import java.util.Date ;
29
30 public final class Log
31 {
32 private static final int DEBUG = 1;
34 private static final int INFO = 2;
35 private static final int WARN = 3;
36 private static final int ERROR = 4;
37 private static final int FATAL = 5;
38
39 private static final Object lock = new Object ();
41
42 private static final SimpleDateFormat dateFormat =
43 new SimpleDateFormat ("MMM dd HH:mm:ss.SSS ");
44 private static final int lineSeparatorLength =
45 System.getProperty("line.separator").length();
46
47 private static boolean logEnabled;
49 private static long maxFileSize;
50 private static int maxBackupIndex;
51 private static int minLevel;
52
53 private static PrintWriter logWriter;
54 private static long fileSize;
55 private static boolean rollOverEnabled;
56
57 private static final void setRollOverEnabled(boolean b)
58 {
59 rollOverEnabled = b;
60 }
61
62 public static final int getLevel()
63 {
64 return minLevel;
65 }
66
67 public static final void setLevel(int level)
68 {
69 minLevel = level;
70 }
71
72 public static final void debug(String s)
73 {
74 log(DEBUG, s);
75 }
76
77 public static final void debug(Throwable t)
78 {
79 log(DEBUG, t);
80 }
81
82 public static final void info(String s)
83 {
84 log(INFO, s);
85 }
86
87 public static final void warn(String s)
88 {
89 log(WARN, s);
90 }
91
92 public static final void warn(Throwable t)
93 {
94 log(WARN, t);
95 }
96
97 public static final void error(String s)
98 {
99 log(ERROR, s);
100 }
101
102 public static final void error(Throwable t)
103 {
104 log(ERROR, t);
105 }
106
107 public static final void fatal(String s)
108 {
109 log(FATAL, s);
110 }
111
112 private static final void log(int level, String s)
113 {
114 if (Editor.isDebugEnabled())
115 System.err.println(s);
116 if (logEnabled && level >= minLevel)
117 writeLog(level, s);
118 }
119
120 private static final void forceLog(int level, String s)
121 {
122 if (Editor.isDebugEnabled())
123 System.err.println(s);
124 writeLog(level, s);
125 }
126
127 private static final void writeLog(int level, String s)
128 {
129 synchronized(lock) {
130 if (logWriter != null) {
131 String dt = getDateTimeString();
132 logWriter.print(dt);
133 logWriter.print(levelToString(level));
134 logWriter.println(s);
135 fileSize += dt.length() + 6 + s.length() + lineSeparatorLength;
136 if (rollOverEnabled && fileSize > maxFileSize)
137 rollOver();
138 }
139 }
140 }
141
142 private static final void log(int level, Throwable t)
143 {
144 if (Editor.isDebugEnabled())
145 t.printStackTrace();
146 if (logEnabled && level >= minLevel) {
147 synchronized(lock) {
148 if (logWriter != null) {
149 String dt = getDateTimeString();
150 logWriter.print(dt);
151 logWriter.print(levelToString(level));
152 StringWriter sw = new StringWriter ();
153 PrintWriter pw = new PrintWriter (sw);
154 t.printStackTrace(pw);
155 String s = sw.toString();
156 logWriter.println(s);
157 fileSize += dt.length() + 6 + s.length() + lineSeparatorLength;
158 if (rollOverEnabled && fileSize > maxFileSize)
159 rollOver();
160 }
161 }
162 }
163 }
164
165 private static final void rollOver()
167 {
168 if (!rollOverEnabled)
169 Debug.bug();
170 setRollOverEnabled(false);
171 long start = System.currentTimeMillis();
172 Log.debug("rotating log files...");
173 for (int i = maxBackupIndex-1; i >= 0; i--) {
174 File source = getBackupLogFile(i);
175 File destination = getBackupLogFile(i+1);
176 if (destination.exists())
177 destination.delete();
178 if (source.isFile())
179 source.renameTo(destination);
180 }
181 File destination = getBackupLogFile(0);
182 File logFile = getLogFile();
183 logWriter.flush();
184 logWriter.close();
185 if (destination.exists())
186 destination.delete();
187 if (logFile.isFile())
188 logFile.renameTo(destination);
189 logWriter = null;
190 fileSize = 0;
191 try {
192 logWriter = new PrintWriter (logFile.getOutputStream(), true);
193 int oldLevel = getLevel();
194 setLevel(INFO);
195 setRollOverEnabled(false);
196 logSystemInformation();
197 logUptime();
198 setRollOverEnabled(true);
199 setLevel(oldLevel);
200 }
201 catch (IOException e) {
202 logEnabled = false;
203 e.printStackTrace();
204 }
205 long elapsed = System.currentTimeMillis() - start;
206 Log.debug("rollOver " + elapsed + " ms");
207 setRollOverEnabled(true);
208 }
209
210 private static final File getLogFile()
211 {
212 return File.getInstance(Directories.getEditorDirectory(), "log");
213 }
214
215 private static final File getBackupLogFile(int index)
216 {
217 return File.getInstance(Directories.getEditorDirectory(),
218 "log.".concat(String.valueOf(index)));
219 }
220
221 public static final void initialize()
222 {
223 synchronized(lock) {
224 Preferences preferences = Editor.preferences();
225 if (preferences != null) {
226 preferences.addPreferencesChangeListener(preferencesChangeListener);
227 loadPreferences();
228 if (logEnabled) {
229 initializeLogWriter();
230 if (logWriter != null) {
231 setLevel(INFO);
232 info("Starting j...");
233 logSystemInformation();
234 if (Editor.isDebugEnabled())
235 setLevel(DEBUG);
236 setRollOverEnabled(true);
237 }
238 }
239 }
240 }
241 }
242
243 private static final void initializeLogWriter()
244 {
245 Debug.assertTrue(logWriter == null);
246 File logFile = getLogFile();
247 if (logFile.isFile())
248 fileSize = logFile.length();
249 try {
250 logWriter = new PrintWriter (logFile.getOutputStream(true), true);
252 }
253 catch (Exception e) {
254 logEnabled = false;
255 e.printStackTrace();
256 }
257 }
258
259 private static final void logSystemInformation()
260 {
261 info(Version.getLongVersionString());
262 String snapshotInformation = Version.getSnapshotInformation();
263 if (snapshotInformation != null)
264 info(snapshotInformation);
265 FastStringBuffer sb = new FastStringBuffer("Java ");
266 sb.append(System.getProperty("java.version"));
267 sb.append(' ');
268 sb.append(System.getProperty("java.vendor"));
269 info(sb.toString());
270 String fullversion = System.getProperty("java.fullversion");
271 if (fullversion != null)
272 info(fullversion);
273 String vm = System.getProperty("java.vm.name");
274 if (vm != null)
275 info(vm);
276 sb.setText(System.getProperty("os.name"));
277 sb.append(' ');
278 sb.append(System.getProperty("os.version"));
279 info(sb.toString());
280 }
281
282 private static final void logUptime()
283 {
284 info("up since ".concat(getDateTimeString(Editor.getStartTimeMillis())));
285 }
286
287 private static final String getDateTimeString()
288 {
289 return getDateTimeString(System.currentTimeMillis());
290 }
291
292 private static final String getDateTimeString(long millis)
293 {
294 return dateFormat.format(new Date (millis));
295 }
296
297 private static final String levelToString(int level)
299 {
300 switch (level) {
301 case DEBUG:
302 return "DEBUG ";
303 case INFO:
304 return " INFO ";
305 case WARN:
306 return " WARN ";
307 case ERROR:
308 return "ERROR ";
309 case FATAL:
310 return "FATAL ";
311 }
312 return "????? ";
314 }
315
316 private static final void loadPreferences()
317 {
318 synchronized(lock) {
319 Preferences preferences = Editor.preferences();
320 logEnabled = preferences.getBooleanProperty(Property.LOG_ENABLED);
321 maxFileSize =
322 preferences.getIntegerProperty(Property.LOG_MAX_FILE_SIZE);
323 if (maxFileSize < 10000)
324 maxFileSize = 10000; else if (maxFileSize > 1000000)
326 maxFileSize = 1000000; maxBackupIndex =
328 preferences.getIntegerProperty(Property.LOG_MAX_BACKUP_INDEX);
329 if (maxBackupIndex < 0)
330 maxBackupIndex = 0; }
332 }
333
334 private static final PreferencesChangeListener preferencesChangeListener =
335 new PreferencesChangeListener() {
336 public void preferencesChanged()
337 {
338 boolean logWasEnabled = logEnabled;
339 loadPreferences();
340 forceLog(DEBUG, "preferencesChanged logEnabled = " + logEnabled);
341 forceLog(DEBUG, "preferencesChanged maxFileSize = " + maxFileSize);
342 forceLog(DEBUG, "preferencesChanged maxBackupIndex = " + maxBackupIndex);
343 if (logEnabled && !logWasEnabled) {
344 initializeLogWriter();
346 if (logWriter != null) {
347 setLevel(INFO);
348 info("Logging enabled");
349 logSystemInformation();
350 logUptime();
351 if (Editor.isDebugEnabled())
352 setLevel(DEBUG);
353 setRollOverEnabled(true);
354 }
355 } else if (logWasEnabled && !logEnabled) {
356 if (logWriter != null) {
358 forceLog(INFO, "Logging disabled");
359 logWriter.flush();
360 logWriter.close();
361 logWriter = null;
362 }
363 } else if (logEnabled) {
364 if (Editor.preferences().getBooleanProperty(Property.DEBUG))
365 setLevel(DEBUG);
366 else
367 setLevel(INFO);
368 }
369 }
370 };
371 }
372 |
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