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TA贡献1808条经验 获得超4个赞
最好使用单个调度程序,但您不需要为此编写自己的调度程序。您可以使用Executors.newScheduledThreadPool(1)具有一定数量线程的单个实例来安排所有任务。
考虑以下代码:
class TaskScheduler {
private ScheduledExecutorService scheduledExecutorService;
public TaskScheduler(int threads) {
this.scheduledExecutorService = Executors.newScheduledThreadPool(threads);
}
//Portion to add task
public TaskExecutionContext schedule(String taskName, Runnable task, long initialDelay, long frequency) {
TaskExecutionContext context = new TaskExecutionContext(taskName);
context.getTaskResult().setFrequencyInSeconds(frequency);
ScheduledFuture scheduledFuture = scheduledExecutorService.scheduleAtFixedRate(task, initialDelay, frequency, TimeUnit.SECONDS);
context.setScheduledFuture(scheduledFuture);
return context;
}
}
class TaskExecutionContext {
private String taskName;
private TaskResult taskResult;
private ScheduledFuture scheduledFuture;
public TaskExecutionContext(String taskName) {
this.taskName = taskName;
this.taskResult = new TaskResult();
this.taskResult.setTaskName(taskName);
this.taskResult.setStartTime(new Date());
//DB Operation on creation
}
public TaskResult stop() {
try {
System.out.println("Stopping : " + this.taskName);
this.taskResult.setTaskName(this.taskName);
this.taskResult.setEndTime(new Date());
scheduledFuture.cancel(false);
//DB Operation on stopping
System.out.println("Stopping : finished - " + this.taskName + " @ " + new Date());
} catch (Exception e) {
e.printStackTrace();
}
return this.taskResult;
}
public TaskResult getTaskResult() {
return this.taskResult;
}
public void setScheduledFuture(ScheduledFuture scheduledFuture) {
this.scheduledFuture = scheduledFuture;
}
}
如果您需要一些关于计划、创建和停止任务的额外操作 - 可能,最好有单独的TaskExecutionContext,它将满足您的所有需求。
当您需要安排任务并将其传递给调度程序时,创建一个上下文。
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