ScheduledExecutorService改为一次性延时任务

 

import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

import org.apache.log4j.Logger;

/**
 * 一次性延时任务
 *
 * @author shay_deng
 * @since: v1.0
 */
public class OneTimeScheduledExecutorService {
    private final static Logger logger = Logger.getLogger(OneTimeScheduledExecutorService.class);
            
    private Map<String, ScheduledExecutorService> taskMap = new HashMap<>();

    /**
     * 添加一个任务
     *
     * @param taskName
     *            任务名称
     * @param command
     *            任务
     * @param delay
     *            延时时间
     * @param unit
     *            时间单位
     */
    public void schedule(String taskName, Runnable command, long delay, TimeUnit unit) {
        if (!taskMap.containsKey(taskName)) {
            ScheduledExecutorService task = Executors.newScheduledThreadPool(1);
            Runnable run = new Runnable() {
                public void run() {

                    command.run();//要做的事

                    if (taskMap.containsKey(taskName)) {// 执行完关闭任务
                        taskMap.get(taskName).shutdownNow();//用完要关掉，要不然占内存
                        taskMap.remove(taskName);
                        logger.info("一次性延时任务 -- >执行完成，删除任务 taskName="+taskName);
                    }
                }
            };
            task.schedule(run, delay, unit);
            taskMap.put(taskName, task);
            logger.info("一次性延时任务 -- >添加任务 taskName="+taskName);
        }
    }

    /**
     * 中途终止任务
     *
     * @param taskName
     *            任务名称
     */
    public void shutdownNow(String taskName) {
        if (taskMap.containsKey(taskName)) {
            taskMap.get(taskName).shutdownNow();
            taskMap.remove(taskName);
            logger.info("一次性延时任务 -- >取消任务 taskName="+taskName);
        }
    }
    
    /**
     * 包含此任务
     *
     * @param taskName
     * @return
     */
    public boolean containsTask(String taskName) {
        return taskMap.containsKey(taskName);
    }
}

 

使用

/**
 * 检查使用状态
 *
 * @author shay_deng
 * @since: v1.0
 */
public class CheckUseStatus {

    private OneTimeScheduledExecutorService task = new OneTimeScheduledExecutorService();//一次性延时任务

    public void checkStatus() {

                        if (添加条件) {
                            if (!task.containsTask(taskName)) {
                                Runnable run = new DelayTask(参数);
                                long delay = xxx
                                task.schedule(taskName, run, delay, TimeUnit.MINUTES);
                            }
                        }
                        else {取消
                            if (task.containsTask(taskName)) {
                                task.shutdownNow(taskName);
                            }
                        }

    }

    /**
     * 任务
     *
     * @author shay_deng
     * @since: v1.0
     */
    class DelayTask implements Runnable {

        public DelayTask(参数) {

        }

        @Override
        public void run() {
            执行
        }
    }
}