kotlin - Kotlin协程，如何异步调用 list 并将结果作为 map 返回

Question

var responseMap = mutableMapOf<VendorType, ChargeResponse>()
  requests.forEach {
    val response = when (it.vendorType) {
        VendorType.Type1 -> service.chargeForType1()
        VendorType.Type2 -> service.chargeForType2()

      else -> {
        throw NotImplementedError("${it.vendorType} does not support yet")
      }
    }
    responseMap[it.vendorType] = response
  }
  responseMap

因此，我希望所有 service.charge函数都在单独的线程中运行。完成后返回 map

Answer 1

希望能解决您的问题:
假设您的服务和要求是这样的:

interface Service {
  suspend fun chargeForType1(): ChargeResponse
  suspend fun chargeForType2(): ChargeResponse
}

data class Request(val vendorType: VendorType)

suspend fun requestAll(requests: List<Request>): Map<VendorType, ChargeResponse> {
  return coroutineScope {
    requests
        .map { request ->
          async {
            request.vendorType to when (request.vendorType) {
              VendorType.Type1 -> service.chargeForType1()
              VendorType.Type2 -> service.chargeForType2()
              else -> throw NotImplementedError("${request.vendorType} does not support yet")
            }
          }
        }
        .awaitAll()
        .toMap()
  }
}