Java 定时任务

来源：互联网发布：齐汇火腿肠知乎编辑：程序博客网时间：2024/06/05 18:56
import java.text.SimpleDateFormat;import java.util.Calendar;import java.util.Date;import java.util.concurrent.Executors;import java.util.concurrent.ScheduledExecutorService;import java.util.concurrent.TimeUnit;/** * 设置开始时间开启任务，间隔时间执行任务，结束时间关闭任务 *  * @author  * */public class ScheduldeExecutorTest { //线程池能按时间计划来执行任务，允许用户设定计划执行任务的时间，int类型的参数是设定   //线程池中线程的最小数目。当任务较多时，线程池可能会自动创建更多的工作线程来执行任务   //此处用Executors.newSingleThreadScheduledExecutor()更佳。     public ScheduledExecutorService scheduExec = Executors.newScheduledThreadPool(1);   //启动计时器   public void lanuchTimer(){        Runnable task = new Runnable() {               public void run() {                        throw new RuntimeException();                    }                };                scheduExec.scheduleWithFixedDelay(task, 1000*5, 1000*10, TimeUnit.MILLISECONDS);   }    //添加新任务   public void addOneTask(){        Runnable task = new Runnable() {                public void run() {               //获取本系统时间，如果大于设定的时间就关闭服务              SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//设置日期格式              String nowDate=df.format(new Date());              int c=timeCompare("2017-01-20 10:42:00", nowDate);              if(0>c){              System.out.println(nowDate+"时间到，关闭任务！");              scheduExec.shutdown();              }else{              System.out.println("==来了");               }            }            };            scheduExec.scheduleWithFixedDelay(task, 1000*1, 2000, TimeUnit.MILLISECONDS);   }   /*时间比大小*/      public static int timeCompare(String t1,String t2){          SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");          Calendar c1=Calendar.getInstance();          Calendar c2=Calendar.getInstance();          try {              c1.setTime(formatter.parse(t1));              c2.setTime(formatter.parse(t2));          } catch (Exception e) {              e.printStackTrace();          }          int result=c1.compareTo(c2);          return result;      }    public static void main(String[] args) throws Exception {  //开启 ScheduldeExecutorTest test = new ScheduldeExecutorTest();            test.lanuchTimer();          //Thread.sleep(1000*5);//5秒钟之后添加新任务            test.addOneTask(); } }
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