1 /*
2 * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.util.prefs;
27
28 import java.util.HashMap;
29 import java.util.HashSet;
30 import java.util.Iterator;
31 import java.util.Timer;
32 import java.util.TimerTask;
33 import java.lang.ref.WeakReference;
34 import sun.misc.ManagedLocalsThread;
35
36
37 /*
38 MacOSXPreferencesFile synchronization:
39
40 Everything is synchronized on MacOSXPreferencesFile.class. This prevents:
41 * simultaneous updates to cachedFiles or changedFiles
42 * simultaneous creation of two objects for the same name+user+host triplet
43 * simultaneous modifications to the same file
44 * modifications during syncWorld/flushWorld
45 * (in MacOSXPreferences.removeNodeSpi()) modification or sync during
46 multi-step node removal process
47 ... among other things.
48 */
49 /*
50 Timers. There are two timers that control synchronization of prefs data to
51 and from disk.
52
53 * Sync timer periodically calls syncWorld() to force external disk changes
54 (e.g. from another VM) into the memory cache. The sync timer runs even
327 syncInterval = -2; // bad property value - default off
328 }
329
330 if (syncInterval > 0) {
331 timer().schedule(new TimerTask() {
332 @Override
333 public void run() {
334 MacOSXPreferencesFile.syncWorld();}
335 }, syncInterval * 1000, syncInterval * 1000);
336 } else {
337 // syncInterval property not set. No sync timer ever.
338 }
339 }
340 }
341
342 // Return the timer used for flush and sync, creating it if necessary.
343 private static synchronized Timer timer()
344 {
345 if (timer == null) {
346 timer = new Timer(true); // daemon
347 Thread flushThread = new ManagedLocalsThread() {
348 @Override
349 public void run() {
350 flushWorld();
351 }
352 };
353 /* Set context class loader to null in order to avoid
354 * keeping a strong reference to an application classloader.
355 */
356 flushThread.setContextClassLoader(null);
357 Runtime.getRuntime().addShutdownHook(flushThread);
358 }
359 return timer;
360 }
361
362
363 // Node manipulation
364 boolean addNode(String path)
365 {
366 synchronized(MacOSXPreferencesFile.class) {
367 markChanged();
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1 /*
2 * Copyright (c) 2011, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.util.prefs;
27
28 import java.util.HashMap;
29 import java.util.HashSet;
30 import java.util.Iterator;
31 import java.util.Timer;
32 import java.util.TimerTask;
33 import java.lang.ref.WeakReference;
34
35
36 /*
37 MacOSXPreferencesFile synchronization:
38
39 Everything is synchronized on MacOSXPreferencesFile.class. This prevents:
40 * simultaneous updates to cachedFiles or changedFiles
41 * simultaneous creation of two objects for the same name+user+host triplet
42 * simultaneous modifications to the same file
43 * modifications during syncWorld/flushWorld
44 * (in MacOSXPreferences.removeNodeSpi()) modification or sync during
45 multi-step node removal process
46 ... among other things.
47 */
48 /*
49 Timers. There are two timers that control synchronization of prefs data to
50 and from disk.
51
52 * Sync timer periodically calls syncWorld() to force external disk changes
53 (e.g. from another VM) into the memory cache. The sync timer runs even
326 syncInterval = -2; // bad property value - default off
327 }
328
329 if (syncInterval > 0) {
330 timer().schedule(new TimerTask() {
331 @Override
332 public void run() {
333 MacOSXPreferencesFile.syncWorld();}
334 }, syncInterval * 1000, syncInterval * 1000);
335 } else {
336 // syncInterval property not set. No sync timer ever.
337 }
338 }
339 }
340
341 // Return the timer used for flush and sync, creating it if necessary.
342 private static synchronized Timer timer()
343 {
344 if (timer == null) {
345 timer = new Timer(true); // daemon
346 Thread flushThread =
347 new Thread(null, null, "Flush Thread", 0, false) {
348 @Override
349 public void run() {
350 flushWorld();
351 }
352 };
353 /* Set context class loader to null in order to avoid
354 * keeping a strong reference to an application classloader.
355 */
356 flushThread.setContextClassLoader(null);
357 Runtime.getRuntime().addShutdownHook(flushThread);
358 }
359 return timer;
360 }
361
362
363 // Node manipulation
364 boolean addNode(String path)
365 {
366 synchronized(MacOSXPreferencesFile.class) {
367 markChanged();
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