mirror of git://gcc.gnu.org/git/gcc.git
918 lines
31 KiB
Java
918 lines
31 KiB
Java
/* Thread -- an independent thread of executable code
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Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
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Free Software Foundation
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This file is part of GNU Classpath.
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GNU Classpath is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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GNU Classpath is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GNU Classpath; see the file COPYING. If not, write to the
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Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301 USA.
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Linking this library statically or dynamically with other modules is
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making a combined work based on this library. Thus, the terms and
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conditions of the GNU General Public License cover the whole
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combination.
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As a special exception, the copyright holders of this library give you
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permission to link this library with independent modules to produce an
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executable, regardless of the license terms of these independent
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modules, and to copy and distribute the resulting executable under
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terms of your choice, provided that you also meet, for each linked
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independent module, the terms and conditions of the license of that
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module. An independent module is a module which is not derived from
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or based on this library. If you modify this library, you may extend
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this exception to your version of the library, but you are not
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obligated to do so. If you do not wish to do so, delete this
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exception statement from your version. */
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package java.lang;
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import gnu.gcj.RawData;
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import gnu.gcj.RawDataManaged;
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/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3
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* "The Java Language Specification", ISBN 0-201-63451-1
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* plus online API docs for JDK 1.2 beta from http://www.javasoft.com.
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* Status: Believed complete to version 1.4, with caveats. We do not
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* implement the deprecated (and dangerous) stop, suspend, and resume
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* methods. Security implementation is not complete.
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*/
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/**
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* Thread represents a single thread of execution in the VM. When an
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* application VM starts up, it creates a non-daemon Thread which calls the
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* main() method of a particular class. There may be other Threads running,
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* such as the garbage collection thread.
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*
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* <p>Threads have names to identify them. These names are not necessarily
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* unique. Every Thread has a priority, as well, which tells the VM which
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* Threads should get more running time. New threads inherit the priority
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* and daemon status of the parent thread, by default.
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*
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* <p>There are two methods of creating a Thread: you may subclass Thread and
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* implement the <code>run()</code> method, at which point you may start the
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* Thread by calling its <code>start()</code> method, or you may implement
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* <code>Runnable</code> in the class you want to use and then call new
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* <code>Thread(your_obj).start()</code>.
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*
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* <p>The virtual machine runs until all non-daemon threads have died (either
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* by returning from the run() method as invoked by start(), or by throwing
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* an uncaught exception); or until <code>System.exit</code> is called with
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* adequate permissions.
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*
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* <p>It is unclear at what point a Thread should be added to a ThreadGroup,
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* and at what point it should be removed. Should it be inserted when it
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* starts, or when it is created? Should it be removed when it is suspended
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* or interrupted? The only thing that is clear is that the Thread should be
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* removed when it is stopped.
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*
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* @author Tom Tromey
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* @author John Keiser
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* @author Eric Blake (ebb9@email.byu.edu)
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* @see Runnable
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* @see Runtime#exit(int)
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* @see #run()
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* @see #start()
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* @see ThreadLocal
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* @since 1.0
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* @status updated to 1.4
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*/
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public class Thread implements Runnable
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{
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/** The minimum priority for a Thread. */
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public static final int MIN_PRIORITY = 1;
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/** The priority a Thread gets by default. */
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public static final int NORM_PRIORITY = 5;
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/** The maximum priority for a Thread. */
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public static final int MAX_PRIORITY = 10;
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/**
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* The group this thread belongs to. This is set to null by
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* ThreadGroup.removeThread when the thread dies.
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*/
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ThreadGroup group;
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/** The object to run(), null if this is the target. */
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private Runnable runnable;
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/** The thread name, non-null. */
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String name;
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/** Whether the thread is a daemon. */
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private boolean daemon;
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/** The thread priority, 1 to 10. */
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private int priority;
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boolean interrupt_flag;
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private boolean alive_flag;
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private boolean startable_flag;
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/** The context classloader for this Thread. */
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private ClassLoader contextClassLoader;
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// This describes the top-most interpreter frame for this thread.
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RawData interp_frame;
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// Our native data - points to an instance of struct natThread.
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private RawDataManaged data;
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/**
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* Allocates a new <code>Thread</code> object. This constructor has
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* the same effect as <code>Thread(null, null,</code>
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* <i>gname</i><code>)</code>, where <b><i>gname</i></b> is
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* a newly generated name. Automatically generated names are of the
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* form <code>"Thread-"+</code><i>n</i>, where <i>n</i> is an integer.
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* <p>
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* Threads created this way must have overridden their
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* <code>run()</code> method to actually do anything. An example
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* illustrating this method being used follows:
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* <p><blockquote><pre>
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* import java.lang.*;
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*
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* class plain01 implements Runnable {
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* String name;
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* plain01() {
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* name = null;
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* }
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* plain01(String s) {
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* name = s;
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* }
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* public void run() {
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* if (name == null)
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* System.out.println("A new thread created");
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* else
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* System.out.println("A new thread with name " + name +
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* " created");
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* }
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* }
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* class threadtest01 {
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* public static void main(String args[] ) {
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* int failed = 0 ;
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*
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* <b>Thread t1 = new Thread();</b>
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* if (t1 != null)
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* System.out.println("new Thread() succeed");
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* else {
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* System.out.println("new Thread() failed");
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* failed++;
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* }
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* }
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* }
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* </pre></blockquote>
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*
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* @see java.lang.Thread#Thread(java.lang.ThreadGroup,
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* java.lang.Runnable, java.lang.String)
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*/
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public Thread()
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{
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this(null, null, gen_name());
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}
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/**
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* Allocates a new <code>Thread</code> object. This constructor has
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* the same effect as <code>Thread(null, target,</code>
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* <i>gname</i><code>)</code>, where <i>gname</i> is
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* a newly generated name. Automatically generated names are of the
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* form <code>"Thread-"+</code><i>n</i>, where <i>n</i> is an integer.
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*
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* @param target the object whose <code>run</code> method is called.
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* @see java.lang.Thread#Thread(java.lang.ThreadGroup,
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* java.lang.Runnable, java.lang.String)
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*/
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public Thread(Runnable target)
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{
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this(null, target, gen_name());
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}
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/**
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* Allocates a new <code>Thread</code> object. This constructor has
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* the same effect as <code>Thread(null, null, name)</code>.
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*
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* @param name the name of the new thread.
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* @see java.lang.Thread#Thread(java.lang.ThreadGroup,
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* java.lang.Runnable, java.lang.String)
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*/
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public Thread(String name)
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{
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this(null, null, name);
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}
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/**
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* Allocates a new <code>Thread</code> object. This constructor has
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* the same effect as <code>Thread(group, target,</code>
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* <i>gname</i><code>)</code>, where <i>gname</i> is
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* a newly generated name. Automatically generated names are of the
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* form <code>"Thread-"+</code><i>n</i>, where <i>n</i> is an integer.
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*
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* @param group the group to put the Thread into
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* @param target the Runnable object to execute
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* @throws SecurityException if this thread cannot access <code>group</code>
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* @throws IllegalThreadStateException if group is destroyed
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* @see #Thread(ThreadGroup, Runnable, String)
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*/
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public Thread(ThreadGroup group, Runnable target)
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{
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this(group, target, gen_name());
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}
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/**
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* Allocates a new <code>Thread</code> object. This constructor has
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* the same effect as <code>Thread(group, null, name)</code>
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*
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* @param group the group to put the Thread into
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* @param name the name for the Thread
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* @throws NullPointerException if name is null
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* @throws SecurityException if this thread cannot access <code>group</code>
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* @throws IllegalThreadStateException if group is destroyed
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* @see #Thread(ThreadGroup, Runnable, String)
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*/
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public Thread(ThreadGroup group, String name)
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{
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this(group, null, name);
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}
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/**
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* Allocates a new <code>Thread</code> object. This constructor has
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* the same effect as <code>Thread(null, target, name)</code>.
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*
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* @param target the Runnable object to execute
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* @param name the name for the Thread
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* @throws NullPointerException if name is null
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* @see #Thread(ThreadGroup, Runnable, String)
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*/
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public Thread(Runnable target, String name)
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{
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this(null, target, name);
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}
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/**
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* Allocate a new Thread object, with the specified ThreadGroup and name, and
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* using the specified Runnable object's <code>run()</code> method to
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* execute. If the Runnable object is null, <code>this</code> (which is
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* a Runnable) is used instead.
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*
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* <p>If the ThreadGroup is null, the security manager is checked. If a
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* manager exists and returns a non-null object for
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* <code>getThreadGroup</code>, that group is used; otherwise the group
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* of the creating thread is used. Note that the security manager calls
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* <code>checkAccess</code> if the ThreadGroup is not null.
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*
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* <p>The new Thread will inherit its creator's priority and daemon status.
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* These can be changed with <code>setPriority</code> and
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* <code>setDaemon</code>.
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*
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* @param group the group to put the Thread into
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* @param target the Runnable object to execute
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* @param name the name for the Thread
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* @throws NullPointerException if name is null
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* @throws SecurityException if this thread cannot access <code>group</code>
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* @throws IllegalThreadStateException if group is destroyed
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* @see Runnable#run()
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* @see #run()
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* @see #setDaemon(boolean)
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* @see #setPriority(int)
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* @see SecurityManager#checkAccess(ThreadGroup)
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* @see ThreadGroup#checkAccess()
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*/
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public Thread(ThreadGroup group, Runnable target, String name)
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{
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this(currentThread(), group, target, name);
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}
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/**
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* Allocate a new Thread object, as if by
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* <code>Thread(group, null, name)</code>, and give it the specified stack
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* size, in bytes. The stack size is <b>highly platform independent</b>,
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* and the virtual machine is free to round up or down, or ignore it
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* completely. A higher value might let you go longer before a
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* <code>StackOverflowError</code>, while a lower value might let you go
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* longer before an <code>OutOfMemoryError</code>. Or, it may do absolutely
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* nothing! So be careful, and expect to need to tune this value if your
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* virtual machine even supports it.
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*
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* @param group the group to put the Thread into
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* @param target the Runnable object to execute
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* @param name the name for the Thread
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* @param size the stack size, in bytes; 0 to be ignored
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* @throws NullPointerException if name is null
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* @throws SecurityException if this thread cannot access <code>group</code>
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* @throws IllegalThreadStateException if group is destroyed
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* @since 1.4
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*/
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public Thread(ThreadGroup group, Runnable target, String name, long size)
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{
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// Just ignore stackSize for now.
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this(currentThread(), group, target, name);
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}
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private Thread (Thread current, ThreadGroup g, Runnable r, String n)
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{
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// Make sure the current thread may create a new thread.
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checkAccess();
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// The Class Libraries book says ``threadName cannot be null''. I
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// take this to mean NullPointerException.
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if (n == null)
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throw new NullPointerException ();
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if (g == null)
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{
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// If CURRENT is null, then we are bootstrapping the first thread.
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// Use ThreadGroup.root, the main threadgroup.
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if (current == null)
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group = ThreadGroup.root;
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else
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group = current.getThreadGroup();
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}
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else
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group = g;
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data = null;
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interrupt_flag = false;
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alive_flag = false;
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startable_flag = true;
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if (current != null)
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{
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group.checkAccess();
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daemon = current.isDaemon();
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int gmax = group.getMaxPriority();
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int pri = current.getPriority();
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priority = (gmax < pri ? gmax : pri);
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contextClassLoader = current.contextClassLoader;
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InheritableThreadLocal.newChildThread(this);
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}
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else
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{
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daemon = false;
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priority = NORM_PRIORITY;
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}
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name = n;
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group.addThread(this);
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runnable = r;
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initialize_native ();
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}
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/**
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* Get the number of active threads in the current Thread's ThreadGroup.
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* This implementation calls
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* <code>currentThread().getThreadGroup().activeCount()</code>.
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*
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* @return the number of active threads in the current ThreadGroup
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* @see ThreadGroup#activeCount()
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*/
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public static int activeCount()
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{
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return currentThread().group.activeCount();
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}
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/**
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* Check whether the current Thread is allowed to modify this Thread. This
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* passes the check on to <code>SecurityManager.checkAccess(this)</code>.
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*
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* @throws SecurityException if the current Thread cannot modify this Thread
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* @see SecurityManager#checkAccess(Thread)
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*/
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public final void checkAccess()
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{
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SecurityManager sm = System.getSecurityManager();
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if (sm != null)
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sm.checkAccess(this);
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}
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/**
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* Count the number of stack frames in this Thread. The Thread in question
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* must be suspended when this occurs.
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*
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* @return the number of stack frames in this Thread
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* @throws IllegalThreadStateException if this Thread is not suspended
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* @deprecated pointless, since suspend is deprecated
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*/
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public native int countStackFrames();
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/**
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* Get the currently executing Thread.
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*
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* @return the currently executing Thread
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*/
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public static native Thread currentThread();
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/**
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* Originally intended to destroy this thread, this method was never
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* implemented by Sun, and is hence a no-op.
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*/
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public void destroy()
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{
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throw new NoSuchMethodError();
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}
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/**
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* Print a stack trace of the current thread to stderr using the same
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* format as Throwable's printStackTrace() method.
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*
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* @see Throwable#printStackTrace()
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*/
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public static void dumpStack()
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{
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(new Exception("Stack trace")).printStackTrace();
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}
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/**
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* Copy every active thread in the current Thread's ThreadGroup into the
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* array. Extra threads are silently ignored. This implementation calls
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* <code>getThreadGroup().enumerate(array)</code>, which may have a
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* security check, <code>checkAccess(group)</code>.
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*
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* @param array the array to place the Threads into
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* @return the number of Threads placed into the array
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* @throws NullPointerException if array is null
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* @throws SecurityException if you cannot access the ThreadGroup
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* @see ThreadGroup#enumerate(Thread[])
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* @see #activeCount()
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* @see SecurityManager#checkAccess(ThreadGroup)
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*/
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public static int enumerate(Thread[] array)
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{
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return currentThread().group.enumerate(array);
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}
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/**
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* Get this Thread's name.
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*
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* @return this Thread's name
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*/
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public final String getName()
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{
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return name;
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}
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|
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/**
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* Get this Thread's priority.
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*
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* @return the Thread's priority
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*/
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public final int getPriority()
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{
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return priority;
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}
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|
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/**
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* Get the ThreadGroup this Thread belongs to. If the thread has died, this
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* returns null.
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*
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* @return this Thread's ThreadGroup
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*/
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public final ThreadGroup getThreadGroup()
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{
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return group;
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}
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|
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/**
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|
* Checks whether the current thread holds the monitor on a given object.
|
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* This allows you to do <code>assert Thread.holdsLock(obj)</code>.
|
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*
|
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* @param obj the object to test lock ownership on.
|
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* @return true if the current thread is currently synchronized on obj
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* @throws NullPointerException if obj is null
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* @since 1.4
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*/
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public static native boolean holdsLock(Object obj);
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|
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/**
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* Interrupt this Thread. First, there is a security check,
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* <code>checkAccess</code>. Then, depending on the current state of the
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* thread, various actions take place:
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*
|
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* <p>If the thread is waiting because of {@link #wait()},
|
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* {@link #sleep(long)}, or {@link #join()}, its <i>interrupt status</i>
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* will be cleared, and an InterruptedException will be thrown. Notice that
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* this case is only possible if an external thread called interrupt().
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*
|
|
* <p>If the thread is blocked in an interruptible I/O operation, in
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* {@link java.nio.channels.InterruptibleChannel}, the <i>interrupt
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* status</i> will be set, and ClosedByInterruptException will be thrown.
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*
|
|
* <p>If the thread is blocked on a {@link java.nio.channels.Selector}, the
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* <i>interrupt status</i> will be set, and the selection will return, with
|
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* a possible non-zero value, as though by the wakeup() method.
|
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*
|
|
* <p>Otherwise, the interrupt status will be set.
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*
|
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* @throws SecurityException if you cannot modify this Thread
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*/
|
|
public native void interrupt();
|
|
|
|
/**
|
|
* Determine whether the current Thread has been interrupted, and clear
|
|
* the <i>interrupted status</i> in the process.
|
|
*
|
|
* @return whether the current Thread has been interrupted
|
|
* @see #isInterrupted()
|
|
*/
|
|
public static boolean interrupted()
|
|
{
|
|
return currentThread().isInterrupted(true);
|
|
}
|
|
|
|
/**
|
|
* Determine whether the given Thread has been interrupted, but leave
|
|
* the <i>interrupted status</i> alone in the process.
|
|
*
|
|
* @return whether the Thread has been interrupted
|
|
* @see #interrupted()
|
|
*/
|
|
public boolean isInterrupted()
|
|
{
|
|
return interrupt_flag;
|
|
}
|
|
|
|
/**
|
|
* Determine whether this Thread is alive. A thread which is alive has
|
|
* started and not yet died.
|
|
*
|
|
* @return whether this Thread is alive
|
|
*/
|
|
public final synchronized boolean isAlive()
|
|
{
|
|
return alive_flag;
|
|
}
|
|
|
|
/**
|
|
* Tell whether this is a daemon Thread or not.
|
|
*
|
|
* @return whether this is a daemon Thread or not
|
|
* @see #setDaemon(boolean)
|
|
*/
|
|
public final boolean isDaemon()
|
|
{
|
|
return daemon;
|
|
}
|
|
|
|
/**
|
|
* Wait forever for the Thread in question to die.
|
|
*
|
|
* @throws InterruptedException if the Thread is interrupted; it's
|
|
* <i>interrupted status</i> will be cleared
|
|
*/
|
|
public final void join() throws InterruptedException
|
|
{
|
|
join(0, 0);
|
|
}
|
|
|
|
/**
|
|
* Wait the specified amount of time for the Thread in question to die.
|
|
*
|
|
* @param ms the number of milliseconds to wait, or 0 for forever
|
|
* @throws InterruptedException if the Thread is interrupted; it's
|
|
* <i>interrupted status</i> will be cleared
|
|
*/
|
|
public final void join(long ms) throws InterruptedException
|
|
{
|
|
join(ms, 0);
|
|
}
|
|
|
|
/**
|
|
* Wait the specified amount of time for the Thread in question to die.
|
|
*
|
|
* <p>Note that 1,000,000 nanoseconds == 1 millisecond, but most VMs do
|
|
* not offer that fine a grain of timing resolution. Besides, there is
|
|
* no guarantee that this thread can start up immediately when time expires,
|
|
* because some other thread may be active. So don't expect real-time
|
|
* performance.
|
|
*
|
|
* @param ms the number of milliseconds to wait, or 0 for forever
|
|
* @param ns the number of extra nanoseconds to sleep (0-999999)
|
|
* @throws InterruptedException if the Thread is interrupted; it's
|
|
* <i>interrupted status</i> will be cleared
|
|
* @throws IllegalArgumentException if ns is invalid
|
|
* @XXX A ThreadListener would be nice, to make this efficient.
|
|
*/
|
|
public final native void join(long ms, int ns)
|
|
throws InterruptedException;
|
|
|
|
/**
|
|
* Resume a suspended thread.
|
|
*
|
|
* @throws SecurityException if you cannot resume the Thread
|
|
* @see #checkAccess()
|
|
* @see #suspend()
|
|
* @deprecated pointless, since suspend is deprecated
|
|
*/
|
|
public final native void resume();
|
|
|
|
private final native void finish_();
|
|
|
|
/**
|
|
* Determine whether the given Thread has been interrupted, but leave
|
|
* the <i>interrupted status</i> alone in the process.
|
|
*
|
|
* @return whether the current Thread has been interrupted
|
|
* @see #interrupted()
|
|
*/
|
|
private boolean isInterrupted(boolean clear_flag)
|
|
{
|
|
boolean r = interrupt_flag;
|
|
if (clear_flag && r)
|
|
{
|
|
// Only clear the flag if we saw it as set. Otherwise this could
|
|
// potentially cause us to miss an interrupt in a race condition,
|
|
// because this method is not synchronized.
|
|
interrupt_flag = false;
|
|
}
|
|
return r;
|
|
}
|
|
|
|
/**
|
|
* The method of Thread that will be run if there is no Runnable object
|
|
* associated with the Thread. Thread's implementation does nothing at all.
|
|
*
|
|
* @see #start()
|
|
* @see #Thread(ThreadGroup, Runnable, String)
|
|
*/
|
|
public void run()
|
|
{
|
|
if (runnable != null)
|
|
runnable.run();
|
|
}
|
|
|
|
/**
|
|
* Set the daemon status of this Thread. If this is a daemon Thread, then
|
|
* the VM may exit even if it is still running. This may only be called
|
|
* before the Thread starts running. There may be a security check,
|
|
* <code>checkAccess</code>.
|
|
*
|
|
* @param daemon whether this should be a daemon thread or not
|
|
* @throws SecurityException if you cannot modify this Thread
|
|
* @throws IllegalThreadStateException if the Thread is active
|
|
* @see #isDaemon()
|
|
* @see #checkAccess()
|
|
*/
|
|
public final void setDaemon(boolean daemon)
|
|
{
|
|
if (!startable_flag)
|
|
throw new IllegalThreadStateException();
|
|
checkAccess();
|
|
this.daemon = daemon;
|
|
}
|
|
|
|
/**
|
|
* Returns the context classloader of this Thread. The context
|
|
* classloader can be used by code that want to load classes depending
|
|
* on the current thread. Normally classes are loaded depending on
|
|
* the classloader of the current class. There may be a security check
|
|
* for <code>RuntimePermission("getClassLoader")</code> if the caller's
|
|
* class loader is not null or an ancestor of this thread's context class
|
|
* loader.
|
|
*
|
|
* @return the context class loader
|
|
* @throws SecurityException when permission is denied
|
|
* @see setContextClassLoader(ClassLoader)
|
|
* @since 1.2
|
|
*/
|
|
public synchronized ClassLoader getContextClassLoader()
|
|
{
|
|
if (contextClassLoader == null)
|
|
contextClassLoader = ClassLoader.getSystemClassLoader();
|
|
|
|
SecurityManager sm = System.getSecurityManager();
|
|
// FIXME: we can't currently find the caller's class loader.
|
|
ClassLoader callers = null;
|
|
if (sm != null && callers != null)
|
|
{
|
|
// See if the caller's class loader is the same as or an
|
|
// ancestor of this thread's class loader.
|
|
while (callers != null && callers != contextClassLoader)
|
|
{
|
|
// FIXME: should use some internal version of getParent
|
|
// that avoids security checks.
|
|
callers = callers.getParent();
|
|
}
|
|
|
|
if (callers != contextClassLoader)
|
|
sm.checkPermission(new RuntimePermission("getClassLoader"));
|
|
}
|
|
|
|
return contextClassLoader;
|
|
}
|
|
|
|
/**
|
|
* Sets the context classloader for this Thread. When not explicitly set,
|
|
* the context classloader for a thread is the same as the context
|
|
* classloader of the thread that created this thread. The first thread has
|
|
* as context classloader the system classloader. There may be a security
|
|
* check for <code>RuntimePermission("setContextClassLoader")</code>.
|
|
*
|
|
* @param classloader the new context class loader
|
|
* @throws SecurityException when permission is denied
|
|
* @see getContextClassLoader()
|
|
* @since 1.2
|
|
*/
|
|
public synchronized void setContextClassLoader(ClassLoader classloader)
|
|
{
|
|
SecurityManager sm = System.getSecurityManager();
|
|
if (sm != null)
|
|
sm.checkPermission(new RuntimePermission("setContextClassLoader"));
|
|
this.contextClassLoader = classloader;
|
|
}
|
|
|
|
/**
|
|
* Set this Thread's name. There may be a security check,
|
|
* <code>checkAccess</code>.
|
|
*
|
|
* @param name the new name for this Thread
|
|
* @throws NullPointerException if name is null
|
|
* @throws SecurityException if you cannot modify this Thread
|
|
*/
|
|
public final void setName(String name)
|
|
{
|
|
checkAccess();
|
|
// The Class Libraries book says ``threadName cannot be null''. I
|
|
// take this to mean NullPointerException.
|
|
if (name == null)
|
|
throw new NullPointerException();
|
|
this.name = name;
|
|
}
|
|
|
|
/**
|
|
* Causes the currently executing thread object to temporarily pause
|
|
* and allow other threads to execute.
|
|
*/
|
|
public static native void yield();
|
|
|
|
/**
|
|
* Suspend the current Thread's execution for the specified amount of
|
|
* time. The Thread will not lose any locks it has during this time. There
|
|
* are no guarantees which thread will be next to run, but most VMs will
|
|
* choose the highest priority thread that has been waiting longest.
|
|
*
|
|
* @param ms the number of milliseconds to sleep, or 0 for forever
|
|
* @throws InterruptedException if the Thread is interrupted; it's
|
|
* <i>interrupted status</i> will be cleared
|
|
* @see #notify()
|
|
* @see #wait(long)
|
|
*/
|
|
public static void sleep(long ms) throws InterruptedException
|
|
{
|
|
sleep(ms, 0);
|
|
}
|
|
|
|
/**
|
|
* Suspend the current Thread's execution for the specified amount of
|
|
* time. The Thread will not lose any locks it has during this time. There
|
|
* are no guarantees which thread will be next to run, but most VMs will
|
|
* choose the highest priority thread that has been waiting longest.
|
|
*
|
|
* <p>Note that 1,000,000 nanoseconds == 1 millisecond, but most VMs do
|
|
* not offer that fine a grain of timing resolution. Besides, there is
|
|
* no guarantee that this thread can start up immediately when time expires,
|
|
* because some other thread may be active. So don't expect real-time
|
|
* performance.
|
|
*
|
|
* @param ms the number of milliseconds to sleep, or 0 for forever
|
|
* @param ns the number of extra nanoseconds to sleep (0-999999)
|
|
* @throws InterruptedException if the Thread is interrupted; it's
|
|
* <i>interrupted status</i> will be cleared
|
|
* @throws IllegalArgumentException if ns is invalid
|
|
* @see #notify()
|
|
* @see #wait(long, int)
|
|
*/
|
|
public static native void sleep(long timeout, int nanos)
|
|
throws InterruptedException;
|
|
|
|
/**
|
|
* Start this Thread, calling the run() method of the Runnable this Thread
|
|
* was created with, or else the run() method of the Thread itself. This
|
|
* is the only way to start a new thread; calling run by yourself will just
|
|
* stay in the same thread. The virtual machine will remove the thread from
|
|
* its thread group when the run() method completes.
|
|
*
|
|
* @throws IllegalThreadStateException if the thread has already started
|
|
* @see #run()
|
|
*/
|
|
public native void start();
|
|
|
|
/**
|
|
* Cause this Thread to stop abnormally because of the throw of a ThreadDeath
|
|
* error. If you stop a Thread that has not yet started, it will stop
|
|
* immediately when it is actually started.
|
|
*
|
|
* <p>This is inherently unsafe, as it can interrupt synchronized blocks and
|
|
* leave data in bad states. Hence, there is a security check:
|
|
* <code>checkAccess(this)</code>, plus another one if the current thread
|
|
* is not this: <code>RuntimePermission("stopThread")</code>. If you must
|
|
* catch a ThreadDeath, be sure to rethrow it after you have cleaned up.
|
|
* ThreadDeath is the only exception which does not print a stack trace when
|
|
* the thread dies.
|
|
*
|
|
* @throws SecurityException if you cannot stop the Thread
|
|
* @see #interrupt()
|
|
* @see #checkAccess()
|
|
* @see #start()
|
|
* @see ThreadDeath
|
|
* @see ThreadGroup#uncaughtException(Thread, Throwable)
|
|
* @see SecurityManager#checkAccess(Thread)
|
|
* @see SecurityManager#checkPermission(Permission)
|
|
* @deprecated unsafe operation, try not to use
|
|
*/
|
|
public final void stop()
|
|
{
|
|
// Argument doesn't matter, because this is no longer
|
|
// supported.
|
|
stop(null);
|
|
}
|
|
|
|
/**
|
|
* Cause this Thread to stop abnormally and throw the specified exception.
|
|
* If you stop a Thread that has not yet started, it will stop immediately
|
|
* when it is actually started. <b>WARNING</b>This bypasses Java security,
|
|
* and can throw a checked exception which the call stack is unprepared to
|
|
* handle. Do not abuse this power.
|
|
*
|
|
* <p>This is inherently unsafe, as it can interrupt synchronized blocks and
|
|
* leave data in bad states. Hence, there is a security check:
|
|
* <code>checkAccess(this)</code>, plus another one if the current thread
|
|
* is not this: <code>RuntimePermission("stopThread")</code>. If you must
|
|
* catch a ThreadDeath, be sure to rethrow it after you have cleaned up.
|
|
* ThreadDeath is the only exception which does not print a stack trace when
|
|
* the thread dies.
|
|
*
|
|
* @param t the Throwable to throw when the Thread dies
|
|
* @throws SecurityException if you cannot stop the Thread
|
|
* @throws NullPointerException in the calling thread, if t is null
|
|
* @see #interrupt()
|
|
* @see #checkAccess()
|
|
* @see #start()
|
|
* @see ThreadDeath
|
|
* @see ThreadGroup#uncaughtException(Thread, Throwable)
|
|
* @see SecurityManager#checkAccess(Thread)
|
|
* @see SecurityManager#checkPermission(Permission)
|
|
* @deprecated unsafe operation, try not to use
|
|
*/
|
|
public final native void stop(Throwable t);
|
|
|
|
/**
|
|
* Suspend this Thread. It will not come back, ever, unless it is resumed.
|
|
*
|
|
* <p>This is inherently unsafe, as the suspended thread still holds locks,
|
|
* and can potentially deadlock your program. Hence, there is a security
|
|
* check: <code>checkAccess</code>.
|
|
*
|
|
* @throws SecurityException if you cannot suspend the Thread
|
|
* @see #checkAccess()
|
|
* @see #resume()
|
|
* @deprecated unsafe operation, try not to use
|
|
*/
|
|
public final native void suspend();
|
|
|
|
/**
|
|
* Set this Thread's priority. There may be a security check,
|
|
* <code>checkAccess</code>, then the priority is set to the smaller of
|
|
* priority and the ThreadGroup maximum priority.
|
|
*
|
|
* @param priority the new priority for this Thread
|
|
* @throws IllegalArgumentException if priority exceeds MIN_PRIORITY or
|
|
* MAX_PRIORITY
|
|
* @throws SecurityException if you cannot modify this Thread
|
|
* @see #getPriority()
|
|
* @see #checkAccess()
|
|
* @see ThreadGroup#getMaxPriority()
|
|
* @see #MIN_PRIORITY
|
|
* @see #MAX_PRIORITY
|
|
*/
|
|
public final native void setPriority(int newPriority);
|
|
|
|
/**
|
|
* Returns a string representation of this thread, including the
|
|
* thread's name, priority, and thread group.
|
|
*
|
|
* @return a human-readable String representing this Thread
|
|
*/
|
|
public String toString()
|
|
{
|
|
return ("Thread[" + name + "," + priority + ","
|
|
+ (group == null ? "" : group.getName()) + "]");
|
|
}
|
|
|
|
private final native void initialize_native();
|
|
|
|
private final native static String gen_name();
|
|
}
|