Runnable接口的源码阅读

/*
 * Copyright (c) 1994, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 */

package java.lang;

/**
 * The <code>Runnable</code> 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</code>.
 * <p>
任意希望其实例通过线程执行的类都需要实现Runnable接口.这些类必须定义一个无参数的run方法
 * This interface is designed to provide a common protocol for objects that
 * wish to execute code while they are active. For example,
 * <code>Runnable</code> is implemented by class <code>Thread</code>.
 * Being active simply means that a thread has been started and has not
 * yet been stopped.
此接口旨在为希望在存活时执行代码的对象提供公共接口.
例如，Runnable被Thread类所实现.存活仅仅意味着线程已经启动了并且还没有被终止.
 * <p>
 * In addition, <code>Runnable</code> provides the means for a class to be
 * active while not subclassing <code>Thread</code>. A class that implements
 * <code>Runnable</code> can run without subclassing <code>Thread</code>
 * by instantiating a <code>Thread</code> instance and passing itself in
 * as the target.  In most cases, the <code>Runnable</code> interface should
 * be used if you are only planning to override the <code>run()</code>
 * method and no other <code>Thread</code> methods.

　　此外，Runnable为不继承Thread的类提供了可用的方法。
　　一个实现了Runnable接口的类可以无需成为Thread的子类而是创建一个Thread并将自身作为参数传递进去的方式被实例化.

　　在大多数情况下，Runnable接口应当用在你只计划重写run方法，并不准备使用其他Thread的方法时

　　(因为Runnable只是一个接口，只有一个抽象的run()，Thread是实现类，有更多其他的方法可被调用)

 * This is important because classes should not be subclassed
 * unless the programmer intends on modifying or enhancing the fundamental
 * behavior of the class.
 *
  这很重要，因为类不应该被子类化除非程序员打算修改或增强基础类的行为.
 * @author  Arthur van Hoff
 * @see     java.lang.Thread
 * @see     java.util.concurrent.Callable
 * @since   JDK1.0
 */
@FunctionalInterface
public interface Runnable {
    /**
     * When an object implementing interface <code>Runnable</code> is used
     * to create a thread, starting the thread causes the object's
     * <code>run</code> method to be called in that separately executing
     * thread.
　当一个对象实现了Runnable接口用于创建线程、启动线程导致对象的run方法在单独执行的线程中被调用
     * <p>
     * The general contract of the method <code>run</code> is that it may
     * take any action whatsoever.
     *

　　run方法的通俗约定是可以做任何行为.

     * @see     java.lang.Thread#run()
     */
    public abstract void run();
}