1 /* 2 * Copyright (c) 2014, 2015, 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 sun.misc; 27 28 /** 29 * A thread that has it's thread locals, and inheritable thread 30 * locals erased on construction. 31 */ 32 public class ManagedLocalsThread extends Thread { 33 private static final Unsafe UNSAFE; 34 private static final long THREAD_LOCALS; 35 private static final long INHERITABLE_THREAD_LOCALS; 36 37 public ManagedLocalsThread() { 38 eraseThreadLocals(); 39 } 40 41 public ManagedLocalsThread(Runnable target) { 42 super(target); 43 eraseThreadLocals(); 44 } 45 46 public ManagedLocalsThread(String name) { 47 super(name); 48 eraseThreadLocals(); 49 } 50 51 public ManagedLocalsThread(ThreadGroup group, Runnable target) { 52 super(group, target); 53 eraseThreadLocals(); 54 } 55 56 public ManagedLocalsThread(Runnable target, String name) { 57 super(target, name); 58 eraseThreadLocals(); 59 } 60 61 public ManagedLocalsThread(ThreadGroup group, String name) { 62 super(group, name); 63 eraseThreadLocals(); 64 } 65 66 public ManagedLocalsThread(ThreadGroup group, Runnable target, String name) { 67 super(group, target, name); 68 eraseThreadLocals(); 69 } 70 71 /** 72 * Drops all thread locals (and inherited thread locals). 73 */ 74 public final void eraseThreadLocals() { 75 UNSAFE.putObject(this, THREAD_LOCALS, null); 76 UNSAFE.putObject(this, INHERITABLE_THREAD_LOCALS, null); 77 } 78 79 static { 80 UNSAFE = Unsafe.getUnsafe(); 81 Class<?> t = Thread.class; 82 try { 83 THREAD_LOCALS = UNSAFE.objectFieldOffset 84 (t.getDeclaredField("threadLocals")); 85 INHERITABLE_THREAD_LOCALS = UNSAFE.objectFieldOffset 86 (t.getDeclaredField("inheritableThreadLocals")); 87 } catch (Exception e) { 88 throw new Error(e); 89 } 90 } 91 } 92