Showing the changes to java/pkg/java/lang/ApplicationShutdownHooks.java (1 of 18352 files). Show all
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| 1 | /* | ||
| 2 | * Copyright (c) 2005, 2010, 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 | package java.lang; | ||
| 26 | |||
| 27 | import java.util.*; | ||
| 28 | |||
| 29 | /* | ||
| 30 | * Class to track and run user level shutdown hooks registered through | ||
| 31 | * <tt>{@link Runtime#addShutdownHook Runtime.addShutdownHook}</tt>. | ||
| 32 | * | ||
| 33 | * @see java.lang.Runtime#addShutdownHook | ||
| 34 | * @see java.lang.Runtime#removeShutdownHook | ||
| 35 | */ | ||
| 36 | |||
| 37 | class ApplicationShutdownHooks { | ||
| 38 | /* The set of registered hooks */ | ||
| 39 | private static IdentityHashMap<Thread, Thread> hooks; | ||
| 40 | static { | ||
| 41 | try { | ||
| 42 | Shutdown.add(1 /* shutdown hook invocation order */, | ||
| 43 | false /* not registered if shutdown in progress */, | ||
| 44 | new Runnable() { | ||
| 45 | public void run() { | ||
| 46 | runHooks(); | ||
| 47 | } | ||
| 48 | } | ||
| 49 | ); | ||
| 50 | hooks = new IdentityHashMap<>(); | ||
| 51 | } catch (IllegalStateException e) { | ||
| 52 | // application shutdown hooks cannot be added if | ||
| 53 | // shutdown is in progress. | ||
| 54 | hooks = null; | ||
| 55 | } | ||
| 56 | } | ||
| 57 | |||
| 58 | |||
| 59 | private ApplicationShutdownHooks() {} | ||
| 60 | |||
| 61 | /* Add a new shutdown hook. Checks the shutdown state and the hook itself, | ||
| 62 | * but does not do any security checks. | ||
| 63 | */ | ||
| 64 | static synchronized void add(Thread hook) { | ||
| 65 | if(hooks == null) | ||
| 66 | throw new IllegalStateException("Shutdown in progress"); | ||
| 67 | |||
| 68 | if (hook.isAlive()) | ||
| 69 | throw new IllegalArgumentException("Hook already running"); | ||
| 70 | |||
| 71 | if (hooks.containsKey(hook)) | ||
| 72 | throw new IllegalArgumentException("Hook previously registered"); | ||
| 73 | |||
| 74 | hooks.put(hook, hook); | ||
| 75 | } | ||
| 76 | |||
| 77 | /* Remove a previously-registered hook. Like the add method, this method | ||
| 78 | * does not do any security checks. | ||
| 79 | */ | ||
| 80 | static synchronized boolean remove(Thread hook) { | ||
| 81 | if(hooks == null) | ||
| 82 | throw new IllegalStateException("Shutdown in progress"); | ||
| 83 | |||
| 84 | if (hook == null) | ||
| 85 | throw new NullPointerException(); | ||
| 86 | |||
| 87 | return hooks.remove(hook) != null; | ||
| 88 | } | ||
| 89 | |||
| 90 | /* Iterates over all application hooks creating a new thread for each | ||
| 91 | * to run in. Hooks are run concurrently and this method waits for | ||
| 92 | * them to finish. | ||
| 93 | */ | ||
| 94 | static void runHooks() { | ||
| 95 | Collection<Thread> threads; | ||
| 96 | synchronized(ApplicationShutdownHooks.class) { | ||
| 97 | threads = hooks.keySet(); | ||
| 98 | hooks = null; | ||
| 99 | } | ||
| 100 | |||
| 101 | for (Thread hook : threads) { | ||
| 102 | hook.start(); | ||
| 103 | } | ||
| 104 | for (Thread hook : threads) { | ||
| 105 | try { | ||
| 106 | hook.join(); | ||
| 107 | } catch (InterruptedException x) { } | ||
| 108 | } | ||
| 109 | } | ||
| 110 | } | ||