Delayed.java

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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
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/*
 * This file is available under and governed by the GNU General Public
 * License version 2 only, as published by the Free Software Foundation.
 * However, the following notice accompanied the original version of this
 * file:
 *
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 */

package java.util.concurrent;

/**
 * A mix-in style interface for marking objects that should be
 * acted upon after a given delay.
 *
 * <p>An implementation of this interface must define a
 * {@code compareTo} method that provides an ordering consistent with
 * its {@code getDelay} method.
 *
 * @author Doug Lea
 * @since 1.5
 */
/*
 * Delayed是一个延时性接口，一般用来约束带有延时属性的任务或组件
 *
 * 与此同时，Delayed还继承了内部比较器Comparable接口，
 * 这意味着该接口的子类本身必须具备"可比较性"，
 */
public interface Delayed extends Comparable<Delayed> {
    /**
     * Returns the remaining delay associated with this object, in the given time unit.
     *
     * @param unit the time unit
     *
     * @return the remaining delay; zero or negative values indicate
     * that the delay has already elapsed
     */
    // 获取距任务触发还剩余的时间
    long getDelay(TimeUnit unit);
}