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/*
* Copyright (c) 1994, 2019, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package java.lang;
/**
* The {@code Runnable} interface should be implemented by any
* class whose instances are intended to be executed by a thread. The
* class must define a method of no arguments called {@code run}.
* <p>
* This interface is designed to provide a common protocol for objects that
* wish to execute code while they are active. For example,
* {@code Runnable} is implemented by class {@code Thread}.
* Being active simply means that a thread has been started and has not
* yet been stopped.
* <p>
* In addition, {@code Runnable} provides the means for a class to be
* active while not subclassing {@code Thread}. A class that implements
* {@code Runnable} can run without subclassing {@code Thread}
* by instantiating a {@code Thread} instance and passing itself in
* as the target. In most cases, the {@code Runnable} interface should
* be used if you are only planning to override the {@code run()}
* method and no other {@code Thread} methods.
* This is important because classes should not be subclassed
* unless the programmer intends on modifying or enhancing the fundamental
* behavior of the class.
*
* @author Arthur van Hoff
* @see java.lang.Thread
* @see java.util.concurrent.Callable
* @since 1.0
*/
@FunctionalInterface
public interface Runnable {
/**
* When an object implementing interface {@code Runnable} is used
* to create a thread, starting the thread causes the object's
* {@code run} method to be called in that separately executing
* thread.
* <p>
* The general contract of the method {@code run} is that it may
* take any action whatsoever.
*
* @see java.lang.Thread#run()
*/
public abstract void run();
}