定時器中 Timer 有單執行緒等缺陷，quartz依賴太重， 用 ScheduledThreadPoolExecutor 又想實現定時排程，實現一個工具類計算初次排程時間即可。

import java.util.concurrent._

val task = new Runnable {
    override def run(): Unit = try {
      doSomething()
    }catch {
      case e: Exception => e.printStackTrace()
    }
}

val ex = new ScheduledThreadPoolExecutor(1
 
)
//晚上10點半開始排程，每天排程一次
ex.scheduleAtFixedRate(task, DateHelper.calcDelay(22, 30, 0), DateHelper.ONE_DAY, TimeUnit.SECONDS)

DateHelper

import java.util.Calendar

object DateHelper {

  val ONE_DAY = 60 * 60 * 24

  /**
    * 計算下次排程開始的時間，單位為秒,24小時制
    **/
  def calcDelay(hour: Int, minute: Int, second: Int): Long = {
    if
 
 (!(0 <= hour && hour <= 23 && 0 <= minute && minute <= 59 && 0 <= second && second <= 59)) {
      throw new IllegalArgumentException()
    }

    val curTime = getCurTime()
    val targetTime = getTargetTime(hour, minute, second)

    //如果已經過了執行時間，執行時間變更為下一天該時段
 

    val delayTime = if (curTime < targetTime) {
      targetTime - curTime
    } else {
      val cal = Calendar.getInstance()
      cal.setTimeInMillis(targetTime)
      cal.add(Calendar.DATE, 1)
      cal.getTimeInMillis - curTime
    }
    delayTime / 1000
  }

  //獲取當前的時間
  private def getCurTime(): Long = {
    val cal = Calendar.getInstance()
    cal.getTimeInMillis
  }

  //獲取下次執行的時間
  private def getTargetTime(hour: Int, minute: Int, second: Int): Long = {
    val cal = Calendar.getInstance()
    cal.set(Calendar.HOUR_OF_DAY, hour)
    cal.set(Calendar.MINUTE, minute)
    cal.set(Calendar.SECOND, second)
    cal.getTimeInMillis
  }
}