Source code: edu/emory/mathcs/util/concurrent/DelegatedRunnable.java
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2 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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4 * The contents of this file are subject to the Mozilla Public License Version
5 * 1.1 (the "License"); you may not use this file except in compliance with
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14 * The Original Code is the Emory Utilities.
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16 * The Initial Developer of the Original Code is
17 * The Distributed Computing Laboratory, Emory University.
18 * Portions created by the Initial Developer are Copyright (C) 2002
19 * the Initial Developer. All Rights Reserved.
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34
35 package edu.emory.mathcs.util.concurrent;
36
37 import java.security.*;
38
39 /**
40 * Wrapper for a runnable that ensures that further executions
41 * (even if performed by different threads) inherit current access control
42 * context and {@link ThreadContext}. In particular, the task will always
43 * run with the same access permissions,
44 * {@link DelegatableThreadLocal delegatable thread locals},
45 * and context class loader, determined
46 * at the time of creation of this DelegatedRunnable.
47 *
48 * @author Dawid Kurzyniec
49 * @version 1.0
50 */
51 public class DelegatedRunnable implements Runnable {
52 final Runnable runnable;
53 final AccessControlContext acc;
54 final ThreadContext tc;
55
56 /**
57 * Construct new DelegatedRunnable wrapper for a given task.
58 * @param runnable the task to wrap
59 */
60 public DelegatedRunnable(Runnable runnable) {
61 this.runnable = runnable;
62 this.acc = AccessController.getContext();
63 this.tc = ThreadContext.getContext();
64 }
65
66 /**
67 * Execute wrapped runnable within access control
68 * context and {@link ThreadContext} associated to this object at
69 * the creation time. In particular, the task will run with the same
70 * access permissions,
71 * {@link DelegatableThreadLocal delegatable thread locals},
72 * and context class loader, as seen when this object was created.
73 */
74 public void run() {
75 AccessController.doPrivileged(new PrivilegedAction() {
76 public Object run() {
77 tc.perform(runnable);
78 return null;
79 }
80 }, acc);
81 }
82 }