CoroutineScope Dispatchers.IO异步操作async返回函数，Kotlin

 

 

 

import kotlinx.coroutines.*fun myFun(a: Int, b: Int, retFun: (sum: Int) -> Unit) {println("分支myFun开始... ${System.currentTimeMillis()}")val task = CoroutineScope(Dispatchers.IO).async(start = CoroutineStart.LAZY) {println("myFun delay... ${System.currentTimeMillis()}")delay(3000)println("myFun delay end ${System.currentTimeMillis()}")a + b}CoroutineScope(Dispatchers.IO).launch {println("myFun launch... ${System.currentTimeMillis()}")val sum = task.await()retFun(sum)println("myFun retFun ${System.currentTimeMillis()}")}println("分支myFun结束 ${System.currentTimeMillis()}")
}fun main(args: Array<String>) {println("主流程开始 ... ${System.currentTimeMillis()}")myFun(1, 2) { sum ->println("主流程等待结果返回...")println("main : $sum ${System.currentTimeMillis()}")println("主流程结果返回")}println("主流程结束 ${System.currentTimeMillis()}")Thread.sleep(5000)
}

 

 

 

主流程开始 ... 1703757127994
分支myFun开始... 1703757127995
分支myFun结束 1703757128042
主流程结束 1703757128042
myFun launch... 1703757128045
myFun delay... 1703757128046
myFun delay end 1703757131050
主流程等待结果返回...
main : 3 1703757131052
主流程结果返回
myFun retFun 1703757131052

Process finished with exit code 0