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最新推荐文章于 2024-03-11 17:03:42 发布

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本文通过具体的Scala案例，展示了如何使用Map进行数据操作，并介绍了case class的定义及应用，同时探讨了JSON解析方法和Scala反射机制的使用。

:q 退出sbt console

Map的使用import scala.collection.mutable.Map

case class StatusChangeMessage(addressId: Option[String], contactName:  Option[String], extraParam:extraMessage)
case class extraMessage(sellerName: Option[String], amount:Option[Int],sellerMobile:  Option[String])

object StatusChangeMessageJsonProtocol extends DefaultJsonProtocol {
  implicit val extraMessageFormat = jsonFormat(extraMessage,"sellerName","amount","sellerMobile")
  implicit val statusChangeMessageFormat = jsonFormat(StatusChangeMessage,"addressId","contactName","extraParam")
}

class OrderDBSavedListener extends MessageListener {

  def consume(message: Message, consumeContext: ConsumeContext): Action = {
    val messageBody = new String(message.getBody, "UTF-8")
    if (message.getReconsumeTimes > 0) {
      CommonUtils.logger.warning("reconsumeTime: " + message.getReconsumeTimes)
    }
    import StatusChangeMessageJsonProtocol._
    try {
          println("12323432423")
          println(messageBody)
          val messageaa=messageBody.parseJson.convertTo[StatusChangeMessage]
          println(messageaa.addressId.getOrElse(""))
          println(messageaa.contactName.getOrElse(""))
          println(messageaa.extraParam.sellerName.getOrElse(""))
        } catch {
      case e: Exception => {
        println(e)
        return Action.ReconsumeLater
      }
    }

Eval的使用

import scala.reflect.runtime.universe
import scala.tools.reflect.ToolBox
val tb = universe.runtimeMirror(getClass.getClassLoader).mkToolBox()
tb.eval(tb.parse("""println("hello!")"""))

函数参数

import scala.util.{Try, Success, Failure}:https://blog.youkuaiyun.com/jasonding1354/article/details/46822417