001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.commons.lang;
018
019 import java.io.File;
020
021 /**
022 * <p>Helpers for <code>java.lang.System</code>.</p>
023 *
024 * <p>If a system property cannot be read due to security restrictions,
025 * the corresponding field in this class will be set to <code>null</code>
026 * and a message will be written to <code>System.err</code>.</p>
027 *
028 * @author Apache Software Foundation
029 * @author Based on code from Avalon Excalibur
030 * @author Based on code from Lucene
031 * @author <a href="mailto:sdowney@panix.com">Steve Downey</a>
032 * @author Gary Gregory
033 * @author Michael Becke
034 * @author Tetsuya Kaneuchi
035 * @author Rafal Krupinski
036 * @author Jason Gritman
037 * @since 1.0
038 * @version $Id: SystemUtils.java 905707 2010-02-02 16:59:59Z niallp $
039 */
040 public class SystemUtils {
041
042 /**
043 * The prefix String for all Windows OS.
044 */
045 private static final String OS_NAME_WINDOWS_PREFIX = "Windows";
046
047 // System property constants
048 //-----------------------------------------------------------------------
049 // These MUST be declared first. Other constants depend on this.
050
051 /**
052 * The System property key for the user home directory.
053 */
054 private static final String USER_HOME_KEY = "user.home";
055
056 /**
057 * The System property key for the user directory.
058 */
059 private static final String USER_DIR_KEY = "user.dir";
060
061 /**
062 * The System property key for the Java IO temporary directory.
063 */
064 private static final String JAVA_IO_TMPDIR_KEY = "java.io.tmpdir";
065
066 /**
067 * The System property key for the Java home directory.
068 */
069 private static final String JAVA_HOME_KEY = "java.home";
070
071 /**
072 * <p>The <code>awt.toolkit</code> System Property.</p>
073 * <p>Holds a class name, on Windows XP this is <code>sun.awt.windows.WToolkit</code>.</p>
074 * <p><b>On platforms without a GUI, this value is <code>null</code>.</b></p>
075 *
076 * <p>Defaults to <code>null</code> if the runtime does not have
077 * security access to read this property or the property does not exist.</p>
078 *
079 * <p>
080 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
081 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
082 * will be out of sync with that System property.
083 * </p>
084 *
085 * @since 2.1
086 */
087 public static final String AWT_TOOLKIT = getSystemProperty("awt.toolkit");
088
089 /**
090 * <p>The <code>file.encoding</code> System Property.</p>
091 * <p>File encoding, such as <code>Cp1252</code>.</p>
092 *
093 * <p>Defaults to <code>null</code> if the runtime does not have
094 * security access to read this property or the property does not exist.</p>
095 *
096 * <p>
097 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
098 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
099 * will be out of sync with that System property.
100 * </p>
101 *
102 * @since 2.0
103 * @since Java 1.2
104 */
105 public static final String FILE_ENCODING = getSystemProperty("file.encoding");
106
107 /**
108 * <p>The <code>file.separator</code> System Property.
109 * File separator (<code>"/"</code> on UNIX).</p>
110 *
111 * <p>Defaults to <code>null</code> if the runtime does not have
112 * security access to read this property or the property does not exist.</p>
113 *
114 * <p>
115 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
116 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
117 * will be out of sync with that System property.
118 * </p>
119 *
120 * @since Java 1.1
121 */
122 public static final String FILE_SEPARATOR = getSystemProperty("file.separator");
123
124 /**
125 * <p>The <code>java.awt.fonts</code> System Property.</p>
126 *
127 * <p>Defaults to <code>null</code> if the runtime does not have
128 * security access to read this property or the property does not exist.</p>
129 *
130 * <p>
131 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
132 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
133 * will be out of sync with that System property.
134 * </p>
135 *
136 * @since 2.1
137 */
138 public static final String JAVA_AWT_FONTS = getSystemProperty("java.awt.fonts");
139
140 /**
141 * <p>The <code>java.awt.graphicsenv</code> System Property.</p>
142 *
143 * <p>Defaults to <code>null</code> if the runtime does not have
144 * security access to read this property or the property does not exist.</p>
145 *
146 * <p>
147 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
148 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
149 * will be out of sync with that System property.
150 * </p>
151 *
152 * @since 2.1
153 */
154 public static final String JAVA_AWT_GRAPHICSENV = getSystemProperty("java.awt.graphicsenv");
155
156 /**
157 * <p>
158 * The <code>java.awt.headless</code> System Property.
159 * The value of this property is the String <code>"true"</code> or <code>"false"</code>.
160 * </p>
161 *
162 * <p>Defaults to <code>null</code> if the runtime does not have
163 * security access to read this property or the property does not exist.</p>
164 *
165 * <p>
166 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
167 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
168 * will be out of sync with that System property.
169 * </p>
170 *
171 * @see #isJavaAwtHeadless()
172 * @since 2.1
173 * @since Java 1.4
174 */
175 public static final String JAVA_AWT_HEADLESS = getSystemProperty("java.awt.headless");
176
177 /**
178 * <p>The <code>java.awt.printerjob</code> System Property.</p>
179 *
180 * <p>Defaults to <code>null</code> if the runtime does not have
181 * security access to read this property or the property does not exist.</p>
182 *
183 * <p>
184 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
185 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
186 * will be out of sync with that System property.
187 * </p>
188 *
189 * @since 2.1
190 */
191 public static final String JAVA_AWT_PRINTERJOB = getSystemProperty("java.awt.printerjob");
192
193 /**
194 * <p>The <code>java.class.path</code> System Property. Java class path.</p>
195 *
196 * <p>Defaults to <code>null</code> if the runtime does not have
197 * security access to read this property or the property does not exist.</p>
198 *
199 * <p>
200 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
201 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
202 * will be out of sync with that System property.
203 * </p>
204 *
205 * @since Java 1.1
206 */
207 public static final String JAVA_CLASS_PATH = getSystemProperty("java.class.path");
208
209 /**
210 * <p>The <code>java.class.version</code> System Property.
211 * Java class format version number.</p>
212 *
213 * <p>Defaults to <code>null</code> if the runtime does not have
214 * security access to read this property or the property does not exist.</p>
215 *
216 * <p>
217 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
218 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
219 * will be out of sync with that System property.
220 * </p>
221 *
222 * @since Java 1.1
223 */
224 public static final String JAVA_CLASS_VERSION = getSystemProperty("java.class.version");
225
226 /**
227 * <p>The <code>java.compiler</code> System Property. Name of JIT compiler to use.
228 * First in JDK version 1.2. Not used in Sun JDKs after 1.2.</p>
229 *
230 * <p>Defaults to <code>null</code> if the runtime does not have
231 * security access to read this property or the property does not exist.</p>
232 *
233 * <p>
234 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
235 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
236 * will be out of sync with that System property.
237 * </p>
238 *
239 * @since Java 1.2. Not used in Sun versions after 1.2.
240 */
241 public static final String JAVA_COMPILER = getSystemProperty("java.compiler");
242
243 /**
244 * <p>The <code>java.endorsed.dirs</code> System Property. Path of endorsed directory
245 * or directories.</p>
246 *
247 * <p>Defaults to <code>null</code> if the runtime does not have
248 * security access to read this property or the property does not exist.</p>
249 *
250 * <p>
251 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
252 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
253 * will be out of sync with that System property.
254 * </p>
255 *
256 * @since Java 1.4
257 */
258 public static final String JAVA_ENDORSED_DIRS = getSystemProperty("java.endorsed.dirs");
259
260 /**
261 * <p>The <code>java.ext.dirs</code> System Property. Path of extension directory
262 * or directories.</p>
263 *
264 * <p>Defaults to <code>null</code> if the runtime does not have
265 * security access to read this property or the property does not exist.</p>
266 *
267 * <p>
268 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
269 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
270 * will be out of sync with that System property.
271 * </p>
272 *
273 * @since Java 1.3
274 */
275 public static final String JAVA_EXT_DIRS = getSystemProperty("java.ext.dirs");
276
277 /**
278 * <p>The <code>java.home</code> System Property. Java installation directory.</p>
279 *
280 * <p>Defaults to <code>null</code> if the runtime does not have
281 * security access to read this property or the property does not exist.</p>
282 *
283 * <p>
284 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
285 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
286 * will be out of sync with that System property.
287 * </p>
288 *
289 * @since Java 1.1
290 */
291 public static final String JAVA_HOME = getSystemProperty(JAVA_HOME_KEY);
292
293 /**
294 * <p>The <code>java.io.tmpdir</code> System Property. Default temp file path.</p>
295 *
296 * <p>Defaults to <code>null</code> if the runtime does not have
297 * security access to read this property or the property does not exist.</p>
298 *
299 * <p>
300 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
301 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
302 * will be out of sync with that System property.
303 * </p>
304 *
305 * @since Java 1.2
306 */
307 public static final String JAVA_IO_TMPDIR = getSystemProperty(JAVA_IO_TMPDIR_KEY);
308
309 /**
310 * <p>The <code>java.library.path</code> System Property. List of paths to search
311 * when loading libraries.</p>
312 *
313 * <p>Defaults to <code>null</code> if the runtime does not have
314 * security access to read this property or the property does not exist.</p>
315 *
316 * <p>
317 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
318 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
319 * will be out of sync with that System property.
320 * </p>
321 *
322 * @since Java 1.2
323 */
324 public static final String JAVA_LIBRARY_PATH = getSystemProperty("java.library.path");
325
326 /**
327 * <p>The <code>java.runtime.name</code> System Property. Java Runtime Environment
328 * name.</p>
329 *
330 * <p>Defaults to <code>null</code> if the runtime does not have
331 * security access to read this property or the property does not exist.</p>
332 *
333 * <p>
334 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
335 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
336 * will be out of sync with that System property.
337 * </p>
338 *
339 * @since 2.0
340 * @since Java 1.3
341 */
342 public static final String JAVA_RUNTIME_NAME = getSystemProperty("java.runtime.name");
343
344 /**
345 * <p>The <code>java.runtime.version</code> System Property. Java Runtime Environment
346 * version.</p>
347 *
348 * <p>Defaults to <code>null</code> if the runtime does not have
349 * security access to read this property or the property does not exist.</p>
350 *
351 * <p>
352 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
353 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
354 * will be out of sync with that System property.
355 * </p>
356 *
357 * @since 2.0
358 * @since Java 1.3
359 */
360 public static final String JAVA_RUNTIME_VERSION = getSystemProperty("java.runtime.version");
361
362 /**
363 * <p>The <code>java.specification.name</code> System Property. Java Runtime Environment
364 * specification name.</p>
365 *
366 * <p>Defaults to <code>null</code> if the runtime does not have
367 * security access to read this property or the property does not exist.</p>
368 *
369 * <p>
370 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
371 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
372 * will be out of sync with that System property.
373 * </p>
374 *
375 * @since Java 1.2
376 */
377 public static final String JAVA_SPECIFICATION_NAME = getSystemProperty("java.specification.name");
378
379 /**
380 * <p>The <code>java.specification.vendor</code> System Property. Java Runtime Environment
381 * specification vendor.</p>
382 *
383 * <p>Defaults to <code>null</code> if the runtime does not have
384 * security access to read this property or the property does not exist.</p>
385 *
386 * <p>
387 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
388 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
389 * will be out of sync with that System property.
390 * </p>
391 *
392 * @since Java 1.2
393 */
394 public static final String JAVA_SPECIFICATION_VENDOR = getSystemProperty("java.specification.vendor");
395
396 /**
397 * <p>The <code>java.specification.version</code> System Property. Java Runtime Environment
398 * specification version.</p>
399 *
400 * <p>Defaults to <code>null</code> if the runtime does not have
401 * security access to read this property or the property does not exist.</p>
402 *
403 * <p>
404 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
405 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
406 * will be out of sync with that System property.
407 * </p>
408 *
409 * @since Java 1.3
410 */
411 public static final String JAVA_SPECIFICATION_VERSION = getSystemProperty("java.specification.version");
412
413 /**
414 * <p>The <code>java.util.prefs.PreferencesFactory</code> System Property. A class name.</p>
415 *
416 * <p>Defaults to <code>null</code> if the runtime does not have
417 * security access to read this property or the property does not exist.</p>
418 *
419 * <p>
420 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
421 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
422 * will be out of sync with that System property.
423 * </p>
424 *
425 * @since 2.1
426 * @since Java 1.4
427 */
428 public static final String JAVA_UTIL_PREFS_PREFERENCES_FACTORY =
429 getSystemProperty("java.util.prefs.PreferencesFactory");
430
431 /**
432 * <p>The <code>java.vendor</code> System Property. Java vendor-specific string.</p>
433 *
434 * <p>Defaults to <code>null</code> if the runtime does not have
435 * security access to read this property or the property does not exist.</p>
436 *
437 * <p>
438 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
439 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
440 * will be out of sync with that System property.
441 * </p>
442 *
443 * @since Java 1.1
444 */
445 public static final String JAVA_VENDOR = getSystemProperty("java.vendor");
446
447 /**
448 * <p>The <code>java.vendor.url</code> System Property. Java vendor URL.</p>
449 *
450 * <p>Defaults to <code>null</code> if the runtime does not have
451 * security access to read this property or the property does not exist.</p>
452 *
453 * <p>
454 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
455 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
456 * will be out of sync with that System property.
457 * </p>
458 *
459 * @since Java 1.1
460 */
461 public static final String JAVA_VENDOR_URL = getSystemProperty("java.vendor.url");
462
463 /**
464 * <p>The <code>java.version</code> System Property. Java version number.</p>
465 *
466 * <p>Defaults to <code>null</code> if the runtime does not have
467 * security access to read this property or the property does not exist.</p>
468 *
469 * <p>
470 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
471 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
472 * will be out of sync with that System property.
473 * </p>
474 *
475 * @since Java 1.1
476 */
477 public static final String JAVA_VERSION = getSystemProperty("java.version");
478
479 /**
480 * <p>The <code>java.vm.info</code> System Property. Java Virtual Machine implementation
481 * info.</p>
482 *
483 * <p>Defaults to <code>null</code> if the runtime does not have
484 * security access to read this property or the property does not exist.</p>
485 *
486 * <p>
487 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
488 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
489 * will be out of sync with that System property.
490 * </p>
491 *
492 * @since 2.0
493 * @since Java 1.2
494 */
495 public static final String JAVA_VM_INFO = getSystemProperty("java.vm.info");
496
497 /**
498 * <p>The <code>java.vm.name</code> System Property. Java Virtual Machine implementation
499 * name.</p>
500 *
501 * <p>Defaults to <code>null</code> if the runtime does not have
502 * security access to read this property or the property does not exist.</p>
503 *
504 * <p>
505 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
506 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
507 * will be out of sync with that System property.
508 * </p>
509 *
510 * @since Java 1.2
511 */
512 public static final String JAVA_VM_NAME = getSystemProperty("java.vm.name");
513
514 /**
515 * <p>The <code>java.vm.specification.name</code> System Property. Java Virtual Machine
516 * specification name.</p>
517 *
518 * <p>Defaults to <code>null</code> if the runtime does not have
519 * security access to read this property or the property does not exist.</p>
520 *
521 * <p>
522 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
523 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
524 * will be out of sync with that System property.
525 * </p>
526 *
527 * @since Java 1.2
528 */
529 public static final String JAVA_VM_SPECIFICATION_NAME = getSystemProperty("java.vm.specification.name");
530
531 /**
532 * <p>The <code>java.vm.specification.vendor</code> System Property. Java Virtual
533 * Machine specification vendor.</p>
534 *
535 * <p>Defaults to <code>null</code> if the runtime does not have
536 * security access to read this property or the property does not exist.</p>
537 *
538 * <p>
539 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
540 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
541 * will be out of sync with that System property.
542 * </p>
543 *
544 * @since Java 1.2
545 */
546 public static final String JAVA_VM_SPECIFICATION_VENDOR = getSystemProperty("java.vm.specification.vendor");
547
548 /**
549 * <p>The <code>java.vm.specification.version</code> System Property. Java Virtual Machine
550 * specification version.</p>
551 *
552 * <p>Defaults to <code>null</code> if the runtime does not have
553 * security access to read this property or the property does not exist.</p>
554 *
555 * <p>
556 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
557 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
558 * will be out of sync with that System property.
559 * </p>
560 *
561 * @since Java 1.2
562 */
563 public static final String JAVA_VM_SPECIFICATION_VERSION = getSystemProperty("java.vm.specification.version");
564
565 /**
566 * <p>The <code>java.vm.vendor</code> System Property. Java Virtual Machine implementation
567 * vendor.</p>
568 *
569 * <p>Defaults to <code>null</code> if the runtime does not have
570 * security access to read this property or the property does not exist.</p>
571 *
572 * <p>
573 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
574 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
575 * will be out of sync with that System property.
576 * </p>
577 *
578 * @since Java 1.2
579 */
580 public static final String JAVA_VM_VENDOR = getSystemProperty("java.vm.vendor");
581
582 /**
583 * <p>The <code>java.vm.version</code> System Property. Java Virtual Machine
584 * implementation version.</p>
585 *
586 * <p>Defaults to <code>null</code> if the runtime does not have
587 * security access to read this property or the property does not exist.</p>
588 *
589 * <p>
590 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
591 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
592 * will be out of sync with that System property.
593 * </p>
594 *
595 * @since Java 1.2
596 */
597 public static final String JAVA_VM_VERSION = getSystemProperty("java.vm.version");
598
599 /**
600 * <p>The <code>line.separator</code> System Property. Line separator
601 * (<code>"\n"</code> on UNIX).</p>
602 *
603 * <p>Defaults to <code>null</code> if the runtime does not have
604 * security access to read this property or the property does not exist.</p>
605 *
606 * <p>
607 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
608 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
609 * will be out of sync with that System property.
610 * </p>
611 *
612 * @since Java 1.1
613 */
614 public static final String LINE_SEPARATOR = getSystemProperty("line.separator");
615
616 /**
617 * <p>The <code>os.arch</code> System Property. Operating system architecture.</p>
618 *
619 * <p>Defaults to <code>null</code> if the runtime does not have
620 * security access to read this property or the property does not exist.</p>
621 *
622 * <p>
623 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
624 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
625 * will be out of sync with that System property.
626 * </p>
627 *
628 * @since Java 1.1
629 */
630 public static final String OS_ARCH = getSystemProperty("os.arch");
631
632 /**
633 * <p>The <code>os.name</code> System Property. Operating system name.</p>
634 *
635 * <p>Defaults to <code>null</code> if the runtime does not have
636 * security access to read this property or the property does not exist.</p>
637 *
638 * <p>
639 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
640 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
641 * will be out of sync with that System property.
642 * </p>
643 *
644 * @since Java 1.1
645 */
646 public static final String OS_NAME = getSystemProperty("os.name");
647
648 /**
649 * <p>The <code>os.version</code> System Property. Operating system version.</p>
650 *
651 * <p>Defaults to <code>null</code> if the runtime does not have
652 * security access to read this property or the property does not exist.</p>
653 *
654 * <p>
655 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
656 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
657 * will be out of sync with that System property.
658 * </p>
659 *
660 * @since Java 1.1
661 */
662 public static final String OS_VERSION = getSystemProperty("os.version");
663
664 /**
665 * <p>The <code>path.separator</code> System Property. Path separator
666 * (<code>":"</code> on UNIX).</p>
667 *
668 * <p>Defaults to <code>null</code> if the runtime does not have
669 * security access to read this property or the property does not exist.</p>
670 *
671 * <p>
672 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
673 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
674 * will be out of sync with that System property.
675 * </p>
676 *
677 * @since Java 1.1
678 */
679 public static final String PATH_SEPARATOR = getSystemProperty("path.separator");
680
681 /**
682 * <p>The <code>user.country</code> or <code>user.region</code> System Property.
683 * User's country code, such as <code>GB</code>. First in JDK version 1.2 as
684 * <code>user.region</code>. Renamed to <code>user.country</code> in 1.4</p>
685 *
686 * <p>Defaults to <code>null</code> if the runtime does not have
687 * security access to read this property or the property does not exist.</p>
688 *
689 * <p>
690 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
691 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
692 * will be out of sync with that System property.
693 * </p>
694 *
695 * @since 2.0
696 * @since Java 1.2
697 */
698 public static final String USER_COUNTRY =
699 getSystemProperty("user.country") == null ?
700 getSystemProperty("user.region") : getSystemProperty("user.country");
701
702 /**
703 * <p>The <code>user.dir</code> System Property. User's current working
704 * directory.</p>
705 *
706 * <p>Defaults to <code>null</code> if the runtime does not have
707 * security access to read this property or the property does not exist.</p>
708 *
709 * <p>
710 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
711 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
712 * will be out of sync with that System property.
713 * </p>
714 *
715 * @since Java 1.1
716 */
717 public static final String USER_DIR = getSystemProperty(USER_DIR_KEY);
718
719 /**
720 * <p>The <code>user.home</code> System Property. User's home directory.</p>
721 *
722 * <p>Defaults to <code>null</code> if the runtime does not have
723 * security access to read this property or the property does not exist.</p>
724 *
725 * <p>
726 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
727 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
728 * will be out of sync with that System property.
729 * </p>
730 *
731 * @since Java 1.1
732 */
733 public static final String USER_HOME = getSystemProperty(USER_HOME_KEY);
734
735 /**
736 * <p>The <code>user.language</code> System Property. User's language code,
737 * such as <code>"en"</code>.</p>
738 *
739 * <p>Defaults to <code>null</code> if the runtime does not have
740 * security access to read this property or the property does not exist.</p>
741 *
742 * <p>
743 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
744 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
745 * will be out of sync with that System property.
746 * </p>
747 *
748 * @since 2.0
749 * @since Java 1.2
750 */
751 public static final String USER_LANGUAGE = getSystemProperty("user.language");
752
753 /**
754 * <p>The <code>user.name</code> System Property. User's account name.</p>
755 *
756 * <p>Defaults to <code>null</code> if the runtime does not have
757 * security access to read this property or the property does not exist.</p>
758 *
759 * <p>
760 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
761 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
762 * will be out of sync with that System property.
763 * </p>
764 *
765 * @since Java 1.1
766 */
767 public static final String USER_NAME = getSystemProperty("user.name");
768
769 /**
770 * <p>The <code>user.timezone</code> System Property.
771 * For example: <code>"America/Los_Angeles"</code>.</p>
772 *
773 * <p>Defaults to <code>null</code> if the runtime does not have
774 * security access to read this property or the property does not exist.</p>
775 *
776 * <p>
777 * This value is initialized when the class is loaded. If {@link System#setProperty(String,String)}
778 * or {@link System#setProperties(java.util.Properties)} is called after this class is loaded, the value
779 * will be out of sync with that System property.
780 * </p>
781 *
782 * @since 2.1
783 */
784 public static final String USER_TIMEZONE = getSystemProperty("user.timezone");
785
786 // Java version
787 //-----------------------------------------------------------------------
788 // This MUST be declared after those above as it depends on the
789 // values being set up
790
791 /**
792 * <p>Gets the Java version as a <code>String</code> trimming leading letters.</p>
793 *
794 * <p>The field will return <code>null</code> if {@link #JAVA_VERSION} is <code>null</code>.</p>
795 *
796 * @since 2.1
797 */
798 public static final String JAVA_VERSION_TRIMMED = getJavaVersionTrimmed();
799
800 // Java version values
801 //-----------------------------------------------------------------------
802 // These MUST be declared after the trim above as they depend on the
803 // value being set up
804
805 /**
806 * <p>Gets the Java version as a <code>float</code>.</p>
807 *
808 * <p>Example return values:</p>
809 * <ul>
810 * <li><code>1.2f</code> for JDK 1.2
811 * <li><code>1.31f</code> for JDK 1.3.1
812 * </ul>
813 *
814 * <p>The field will return zero if {@link #JAVA_VERSION} is <code>null</code>.</p>
815 *
816 * @since 2.0
817 */
818 public static final float JAVA_VERSION_FLOAT = getJavaVersionAsFloat();
819
820 /**
821 * <p>Gets the Java version as an <code>int</code>.</p>
822 *
823 * <p>Example return values:</p>
824 * <ul>
825 * <li><code>120</code> for JDK 1.2
826 * <li><code>131</code> for JDK 1.3.1
827 * </ul>
828 *
829 * <p>The field will return zero if {@link #JAVA_VERSION} is <code>null</code>.</p>
830 *
831 * @since 2.0
832 */
833 public static final int JAVA_VERSION_INT = getJavaVersionAsInt();
834
835 // Java version checks
836 //-----------------------------------------------------------------------
837 // These MUST be declared after those above as they depend on the
838 // values being set up
839
840 /**
841 * <p>Is <code>true</code> if this is Java version 1.1 (also 1.1.x versions).</p>
842 *
843 * <p>The field will return <code>false</code> if {@link #JAVA_VERSION} is
844 * <code>null</code>.</p>
845 */
846 public static final boolean IS_JAVA_1_1 = getJavaVersionMatches("1.1");
847
848 /**
849 * <p>Is <code>true</code> if this is Java version 1.2 (also 1.2.x versions).</p>
850 *
851 * <p>The field will return <code>false</code> if {@link #JAVA_VERSION} is
852 * <code>null</code>.</p>
853 */
854 public static final boolean IS_JAVA_1_2 = getJavaVersionMatches("1.2");
855
856 /**
857 * <p>Is <code>true</code> if this is Java version 1.3 (also 1.3.x versions).</p>
858 *
859 * <p>The field will return <code>false</code> if {@link #JAVA_VERSION} is
860 * <code>null</code>.</p>
861 */
862 public static final boolean IS_JAVA_1_3 = getJavaVersionMatches("1.3");
863
864 /**
865 * <p>Is <code>true</code> if this is Java version 1.4 (also 1.4.x versions).</p>
866 *
867 * <p>The field will return <code>false</code> if {@link #JAVA_VERSION} is
868 * <code>null</code>.</p>
869 */
870 public static final boolean IS_JAVA_1_4 = getJavaVersionMatches("1.4");
871
872 /**
873 * <p>Is <code>true</code> if this is Java version 1.5 (also 1.5.x versions).</p>
874 *
875 * <p>The field will return <code>false</code> if {@link #JAVA_VERSION} is
876 * <code>null</code>.</p>
877 */
878 public static final boolean IS_JAVA_1_5 = getJavaVersionMatches("1.5");
879
880 /**
881 * <p>Is <code>true</code> if this is Java version 1.6 (also 1.6.x versions).</p>
882 *
883 * <p>The field will return <code>false</code> if {@link #JAVA_VERSION} is
884 * <code>null</code>.</p>
885 */
886 public static final boolean IS_JAVA_1_6 = getJavaVersionMatches("1.6");
887
888 /**
889 * <p>Is <code>true</code> if this is Java version 1.7 (also 1.7.x versions).</p>
890 *
891 * <p>The field will return <code>false</code> if {@link #JAVA_VERSION} is
892 * <code>null</code>.</p>
893 *
894 * @since 2.5
895 */
896 public static final boolean IS_JAVA_1_7 = getJavaVersionMatches("1.7");
897
898 // Operating system checks
899 //-----------------------------------------------------------------------
900 // These MUST be declared after those above as they depend on the
901 // values being set up
902 // OS names from http://www.vamphq.com/os.html
903 // Selected ones included - please advise dev@commons.apache.org
904 // if you want another added or a mistake corrected
905
906 /**
907 * <p>Is <code>true</code> if this is AIX.</p>
908 *
909 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
910 * <code>null</code>.</p>
911 *
912 * @since 2.0
913 */
914 public static final boolean IS_OS_AIX = getOSMatches("AIX");
915
916 /**
917 * <p>Is <code>true</code> if this is HP-UX.</p>
918 *
919 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
920 * <code>null</code>.</p>
921 *
922 * @since 2.0
923 */
924 public static final boolean IS_OS_HP_UX = getOSMatches("HP-UX");
925
926 /**
927 * <p>Is <code>true</code> if this is Irix.</p>
928 *
929 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
930 * <code>null</code>.</p>
931 *
932 * @since 2.0
933 */
934 public static final boolean IS_OS_IRIX = getOSMatches("Irix");
935
936 /**
937 * <p>Is <code>true</code> if this is Linux.</p>
938 *
939 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
940 * <code>null</code>.</p>
941 *
942 * @since 2.0
943 */
944 public static final boolean IS_OS_LINUX = getOSMatches("Linux") || getOSMatches("LINUX");
945
946 /**
947 * <p>Is <code>true</code> if this is Mac.</p>
948 *
949 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
950 * <code>null</code>.</p>
951 *
952 * @since 2.0
953 */
954 public static final boolean IS_OS_MAC = getOSMatches("Mac");
955
956 /**
957 * <p>Is <code>true</code> if this is Mac.</p>
958 *
959 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
960 * <code>null</code>.</p>
961 *
962 * @since 2.0
963 */
964 public static final boolean IS_OS_MAC_OSX = getOSMatches("Mac OS X");
965
966 /**
967 * <p>Is <code>true</code> if this is OS/2.</p>
968 *
969 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
970 * <code>null</code>.</p>
971 *
972 * @since 2.0
973 */
974 public static final boolean IS_OS_OS2 = getOSMatches("OS/2");
975
976 /**
977 * <p>Is <code>true</code> if this is Solaris.</p>
978 *
979 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
980 * <code>null</code>.</p>
981 *
982 * @since 2.0
983 */
984 public static final boolean IS_OS_SOLARIS = getOSMatches("Solaris");
985
986 /**
987 * <p>Is <code>true</code> if this is SunOS.</p>
988 *
989 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
990 * <code>null</code>.</p>
991 *
992 * @since 2.0
993 */
994 public static final boolean IS_OS_SUN_OS = getOSMatches("SunOS");
995
996 /**
997 * <p>Is <code>true</code> if this is a POSIX compilant system,
998 * as in any of AIX, HP-UX, Irix, Linux, MacOSX, Solaris or SUN OS.</p>
999 *
1000 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
1001 * <code>null</code>.</p>
1002 *
1003 * @since 2.1
1004 */
1005 public static final boolean IS_OS_UNIX =
1006 IS_OS_AIX || IS_OS_HP_UX || IS_OS_IRIX || IS_OS_LINUX ||
1007 IS_OS_MAC_OSX || IS_OS_SOLARIS || IS_OS_SUN_OS;
1008
1009 /**
1010 * <p>Is <code>true</code> if this is Windows.</p>
1011 *
1012 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
1013 * <code>null</code>.</p>
1014 *
1015 * @since 2.0
1016 */
1017 public static final boolean IS_OS_WINDOWS = getOSMatches(OS_NAME_WINDOWS_PREFIX);
1018
1019 /**
1020 * <p>Is <code>true</code> if this is Windows 2000.</p>
1021 *
1022 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
1023 * <code>null</code>.</p>
1024 *
1025 * @since 2.0
1026 */
1027 public static final boolean IS_OS_WINDOWS_2000 = getOSMatches(OS_NAME_WINDOWS_PREFIX, "5.0");
1028
1029 /**
1030 * <p>Is <code>true</code> if this is Windows 95.</p>
1031 *
1032 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
1033 * <code>null</code>.</p>
1034 *
1035 * @since 2.0
1036 */
1037 public static final boolean IS_OS_WINDOWS_95 = getOSMatches(OS_NAME_WINDOWS_PREFIX + " 9", "4.0");
1038 // JDK 1.2 running on Windows98 returns 'Windows 95', hence the above
1039
1040 /**
1041 * <p>Is <code>true</code> if this is Windows 98.</p>
1042 *
1043 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
1044 * <code>null</code>.</p>
1045 *
1046 * @since 2.0
1047 */
1048 public static final boolean IS_OS_WINDOWS_98 = getOSMatches(OS_NAME_WINDOWS_PREFIX + " 9", "4.1");
1049 // JDK 1.2 running on Windows98 returns 'Windows 95', hence the above
1050
1051 /**
1052 * <p>Is <code>true</code> if this is Windows ME.</p>
1053 *
1054 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
1055 * <code>null</code>.</p>
1056 *
1057 * @since 2.0
1058 */
1059 public static final boolean IS_OS_WINDOWS_ME = getOSMatches(OS_NAME_WINDOWS_PREFIX, "4.9");
1060 // JDK 1.2 running on WindowsME may return 'Windows 95', hence the above
1061
1062 /**
1063 * <p>Is <code>true</code> if this is Windows NT.</p>
1064 *
1065 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
1066 * <code>null</code>.</p>
1067 *
1068 * @since 2.0
1069 */
1070 public static final boolean IS_OS_WINDOWS_NT = getOSMatches(OS_NAME_WINDOWS_PREFIX + " NT");
1071 // Windows 2000 returns 'Windows 2000' but may suffer from same JDK1.2 problem
1072
1073 /**
1074 * <p>Is <code>true</code> if this is Windows XP.</p>
1075 *
1076 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
1077 * <code>null</code>.</p>
1078 *
1079 * @since 2.0
1080 */
1081 public static final boolean IS_OS_WINDOWS_XP = getOSMatches(OS_NAME_WINDOWS_PREFIX, "5.1");
1082
1083 //-----------------------------------------------------------------------
1084 /**
1085 * <p>Is <code>true</code> if this is Windows Vista.</p>
1086 *
1087 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
1088 * <code>null</code>.</p>
1089 *
1090 * @since 2.4
1091 */
1092 public static final boolean IS_OS_WINDOWS_VISTA = getOSMatches(OS_NAME_WINDOWS_PREFIX, "6.0");
1093
1094 /**
1095 * <p>Is <code>true</code> if this is Windows 7.</p>
1096 *
1097 * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
1098 * <code>null</code>.</p>
1099 *
1100 * @since 2.5
1101 */
1102 public static final boolean IS_OS_WINDOWS_7 = getOSMatches(OS_NAME_WINDOWS_PREFIX, "6.1");
1103
1104 //-----------------------------------------------------------------------
1105 /**
1106 * <p>SystemUtils instances should NOT be constructed in standard
1107 * programming. Instead, the class should be used as
1108 * <code>SystemUtils.FILE_SEPARATOR</code>.</p>
1109 *
1110 * <p>This constructor is public to permit tools that require a JavaBean
1111 * instance to operate.</p>
1112 */
1113 public SystemUtils() {
1114 super();
1115 }
1116
1117 //-----------------------------------------------------------------------
1118 /**
1119 * <p>Gets the Java version number as a <code>float</code>.</p>
1120 *
1121 * <p>Example return values:</p>
1122 * <ul>
1123 * <li><code>1.2f</code> for JDK 1.2
1124 * <li><code>1.31f</code> for JDK 1.3.1
1125 * </ul>
1126 *
1127 * @return the version, for example 1.31f for JDK 1.3.1
1128 * @deprecated Use {@link #JAVA_VERSION_FLOAT} instead.
1129 * Method will be removed in Commons Lang 3.0.
1130 */
1131 public static float getJavaVersion() {
1132 return JAVA_VERSION_FLOAT;
1133 }
1134
1135 /**
1136 * <p>Gets the Java version number as a <code>float</code>.</p>
1137 *
1138 * <p>Example return values:</p>
1139 * <ul>
1140 * <li><code>1.2f</code> for JDK 1.2
1141 * <li><code>1.31f</code> for JDK 1.3.1
1142 * </ul>
1143 *
1144 * <p>Patch releases are not reported.
1145 * Zero is returned if {@link #JAVA_VERSION_TRIMMED} is <code>null</code>.</p>
1146 *
1147 * @return the version, for example 1.31f for JDK 1.3.1
1148 */
1149 private static float getJavaVersionAsFloat() {
1150 if (JAVA_VERSION_TRIMMED == null) {
1151 return 0f;
1152 }
1153 String str = JAVA_VERSION_TRIMMED.substring(0, 3);
1154 if (JAVA_VERSION_TRIMMED.length() >= 5) {
1155 str = str + JAVA_VERSION_TRIMMED.substring(4, 5);
1156 }
1157 try {
1158 return Float.parseFloat(str);
1159 } catch (Exception ex) {
1160 return 0;
1161 }
1162 }
1163
1164 /**
1165 * <p>Gets the Java version number as an <code>int</code>.</p>
1166 *
1167 * <p>Example return values:</p>
1168 * <ul>
1169 * <li><code>120</code> for JDK 1.2
1170 * <li><code>131</code> for JDK 1.3.1
1171 * </ul>
1172 *
1173 * <p>Patch releases are not reported.
1174 * Zero is returned if {@link #JAVA_VERSION_TRIMMED} is <code>null</code>.</p>
1175 *
1176 * @return the version, for example 131 for JDK 1.3.1
1177 */
1178 private static int getJavaVersionAsInt() {
1179 if (JAVA_VERSION_TRIMMED == null) {
1180 return 0;
1181 }
1182 String str = JAVA_VERSION_TRIMMED.substring(0, 1);
1183 str = str + JAVA_VERSION_TRIMMED.substring(2, 3);
1184 if (JAVA_VERSION_TRIMMED.length() >= 5) {
1185 str = str + JAVA_VERSION_TRIMMED.substring(4, 5);
1186 } else {
1187 str = str + "0";
1188 }
1189 try {
1190 return Integer.parseInt(str);
1191 } catch (Exception ex) {
1192 return 0;
1193 }
1194 }
1195
1196 /**
1197 * Trims the text of the java version to start with numbers.
1198 *
1199 * @return the trimmed java version
1200 */
1201 private static String getJavaVersionTrimmed() {
1202 if (JAVA_VERSION != null) {
1203 for (int i = 0; i < JAVA_VERSION.length(); i++) {
1204 char ch = JAVA_VERSION.charAt(i);
1205 if (ch >= '0' && ch <= '9') {
1206 return JAVA_VERSION.substring(i);
1207 }
1208 }
1209 }
1210 return null;
1211 }
1212
1213 /**
1214 * <p>Decides if the java version matches.</p>
1215 *
1216 * @param versionPrefix the prefix for the java version
1217 * @return true if matches, or false if not or can't determine
1218 */
1219 private static boolean getJavaVersionMatches(String versionPrefix) {
1220 if (JAVA_VERSION_TRIMMED == null) {
1221 return false;
1222 }
1223 return JAVA_VERSION_TRIMMED.startsWith(versionPrefix);
1224 }
1225
1226 /**
1227 * <p>Decides if the operating system matches.</p>
1228 *
1229 * @param osNamePrefix the prefix for the os name
1230 * @return true if matches, or false if not or can't determine
1231 */
1232 private static boolean getOSMatches(String osNamePrefix) {
1233 if (OS_NAME == null) {
1234 return false;
1235 }
1236 return OS_NAME.startsWith(osNamePrefix);
1237 }
1238
1239 /**
1240 * <p>Decides if the operating system matches.</p>
1241 *
1242 * @param osNamePrefix the prefix for the os name
1243 * @param osVersionPrefix the prefix for the version
1244 * @return true if matches, or false if not or can't determine
1245 */
1246 private static boolean getOSMatches(String osNamePrefix, String osVersionPrefix) {
1247 if (OS_NAME == null || OS_VERSION == null) {
1248 return false;
1249 }
1250 return OS_NAME.startsWith(osNamePrefix) && OS_VERSION.startsWith(osVersionPrefix);
1251 }
1252
1253 //-----------------------------------------------------------------------
1254 /**
1255 * <p>Gets a System property, defaulting to <code>null</code> if the property
1256 * cannot be read.</p>
1257 *
1258 * <p>If a <code>SecurityException</code> is caught, the return
1259 * value is <code>null</code> and a message is written to <code>System.err</code>.</p>
1260 *
1261 * @param property the system property name
1262 * @return the system property value or <code>null</code> if a security problem occurs
1263 */
1264 private static String getSystemProperty(String property) {
1265 try {
1266 return System.getProperty(property);
1267 } catch (SecurityException ex) {
1268 // we are not allowed to look at this property
1269 System.err.println(
1270 "Caught a SecurityException reading the system property '" + property
1271 + "'; the SystemUtils property value will default to null."
1272 );
1273 return null;
1274 }
1275 }
1276
1277 /**
1278 * <p>Is the Java version at least the requested version.</p>
1279 *
1280 * <p>Example input:</p>
1281 * <ul>
1282 * <li><code>1.2f</code> to test for JDK 1.2</li>
1283 * <li><code>1.31f</code> to test for JDK 1.3.1</li>
1284 * </ul>
1285 *
1286 * @param requiredVersion the required version, for example 1.31f
1287 * @return <code>true</code> if the actual version is equal or greater
1288 * than the required version
1289 */
1290 public static boolean isJavaVersionAtLeast(float requiredVersion) {
1291 return JAVA_VERSION_FLOAT >= requiredVersion;
1292 }
1293
1294 /**
1295 * <p>Is the Java version at least the requested version.</p>
1296 *
1297 * <p>Example input:</p>
1298 * <ul>
1299 * <li><code>120</code> to test for JDK 1.2 or greater</li>
1300 * <li><code>131</code> to test for JDK 1.3.1 or greater</li>
1301 * </ul>
1302 *
1303 * @param requiredVersion the required version, for example 131
1304 * @return <code>true</code> if the actual version is equal or greater
1305 * than the required version
1306 * @since 2.0
1307 */
1308 public static boolean isJavaVersionAtLeast(int requiredVersion) {
1309 return JAVA_VERSION_INT >= requiredVersion;
1310 }
1311
1312 /**
1313 * Returns whether the {@link #JAVA_AWT_HEADLESS} value is <code>true</code>.
1314 *
1315 * @return <code>true</code> if <code>JAVA_AWT_HEADLESS</code> is <code>"true"</code>,
1316 * <code>false</code> otherwise.
1317 *
1318 * @see #JAVA_AWT_HEADLESS
1319 * @since 2.1
1320 * @since Java 1.4
1321 */
1322 public static boolean isJavaAwtHeadless() {
1323 return JAVA_AWT_HEADLESS != null ? JAVA_AWT_HEADLESS.equals(Boolean.TRUE.toString()) : false;
1324 }
1325 /**
1326 * <p>Gets the Java home directory as a <code>File</code>.</p>
1327 *
1328 * @return a directory
1329 * @throws SecurityException if a security manager exists and its
1330 * <code>checkPropertyAccess</code> method doesn't allow
1331 * access to the specified system property.
1332 * @see System#getProperty(String)
1333 * @since 2.1
1334 */
1335 public static File getJavaHome() {
1336 return new File(System.getProperty(JAVA_HOME_KEY));
1337 }
1338
1339 /**
1340 * <p>Gets the Java IO temporary directory as a <code>File</code>.</p>
1341 *
1342 * @return a directory
1343 * @throws SecurityException if a security manager exists and its
1344 * <code>checkPropertyAccess</code> method doesn't allow
1345 * access to the specified system property.
1346 * @see System#getProperty(String)
1347 * @since 2.1
1348 */
1349 public static File getJavaIoTmpDir() {
1350 return new File(System.getProperty(JAVA_IO_TMPDIR_KEY));
1351 }
1352
1353 /**
1354 * <p>Gets the user directory as a <code>File</code>.</p>
1355 *
1356 * @return a directory
1357 * @throws SecurityException if a security manager exists and its
1358 * <code>checkPropertyAccess</code> method doesn't allow
1359 * access to the specified system property.
1360 * @see System#getProperty(String)
1361 * @since 2.1
1362 */
1363 public static File getUserDir() {
1364 return new File(System.getProperty(USER_DIR_KEY));
1365 }
1366
1367 /**
1368 * <p>Gets the user home directory as a <code>File</code>.</p>
1369 *
1370 * @return a directory
1371 * @throws SecurityException if a security manager exists and its
1372 * <code>checkPropertyAccess</code> method doesn't allow
1373 * access to the specified system property.
1374 * @see System#getProperty(String)
1375 * @since 2.1
1376 */
1377 public static File getUserHome() {
1378 return new File(System.getProperty(USER_HOME_KEY));
1379 }
1380
1381 }