2362N/A * Copyright (c) 2008, 2009, Oracle and/or its affiliates. All rights reserved. 893N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 893N/A * This code is free software; you can redistribute it and/or modify it 893N/A * under the terms of the GNU General Public License version 2 only, as 2362N/A * published by the Free Software Foundation. Oracle designates this 893N/A * particular file as subject to the "Classpath" exception as provided 2362N/A * by Oracle in the LICENSE file that accompanied this code. 893N/A * This code is distributed in the hope that it will be useful, but WITHOUT 893N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 893N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 893N/A * version 2 for more details (a copy is included in the LICENSE file that 893N/A * accompanied this code). 893N/A * You should have received a copy of the GNU General Public License version 893N/A * 2 along with this work; if not, write to the Free Software Foundation, 893N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 2362N/A * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2362N/A * or visit www.oracle.com if you need additional information or have any 893N/A * Base implementation of a task (typically native) that polls a memory location 893N/A * task is executed by invoking the {@link runInterruptibly} method defined 893N/A * here and cancelled by invoking Thread.interrupt. 893N/A // the following require lock when examining or changing 893N/A * Returns the memory address of a 4-byte int that should be polled to 893N/A * The value to write to the polled memory location to indicate that the 893N/A * task has been cancelled. If this method is not overridden then it 893N/A * defaults to MAX_VALUE. 893N/A * "cancels" the task by writing bits into memory location that it polled 893N/A * Returns the exception thrown by the task or null if the task completed 893N/A * The task body. This should periodically poll the memory location 893N/A * to check for cancellation. 893N/A * Invokes the given task in its own thread. If this (meaning the current) 893N/A * thread is interrupted then an attempt is make to cancel the background 893N/A * thread by writing into the memory location that it polls cooperatively.