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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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,
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 *
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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();
}