1/*
2 * Copyright (c) 1994, 2005, 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
26package java.lang;
27
28/**
29 * The <code>Runnable</code> interface should be implemented by any
30 * class whose instances are intended to be executed by a thread. The
31 * class must define a method of no arguments called <code>run</code>.
32 * <p>
33 * This interface is designed to provide a common protocol for objects that
34 * wish to execute code while they are active. For example,
35 * <code>Runnable</code> is implemented by class <code>Thread</code>.
36 * Being active simply means that a thread has been started and has not
37 * yet been stopped.
38 * <p>
39 * In addition, <code>Runnable</code> provides the means for a class to be
40 * active while not subclassing <code>Thread</code>. A class that implements
41 * <code>Runnable</code> can run without subclassing <code>Thread</code>
42 * by instantiating a <code>Thread</code> instance and passing itself in
43 * as the target.  In most cases, the <code>Runnable</code> interface should
44 * be used if you are only planning to override the <code>run()</code>
45 * method and no other <code>Thread</code> methods.
46 * This is important because classes should not be subclassed
47 * unless the programmer intends on modifying or enhancing the fundamental
48 * behavior of the class.
49 *
50 * @author  Arthur van Hoff
51 * @see     java.lang.Thread
52 * @see     java.util.concurrent.Callable
53 * @since   JDK1.0
54 */
55public
56interface Runnable {
57    /**
58     * When an object implementing interface <code>Runnable</code> is used
59     * to create a thread, starting the thread causes the object's
60     * <code>run</code> method to be called in that separately executing
61     * thread.
62     * <p>
63     * The general contract of the method <code>run</code> is that it may
64     * take any action whatsoever.
65     *
66     * @see     java.lang.Thread#run()
67     */
68    public abstract void run();
69}
70