Question

这不是任何形式的任务。我正在使用Akka Actors学习Scala和Scala并发。我这样做的一种方法是提出一些简单的程序设计，并试图提出一个涉及应用于设计的Actors / concurrency的实现：

我想写的程序是储蓄银行账户应用程序，它有一个输入组件和一个输出组件。
Bank XYZ向客户提供开立储蓄账户的计划
1）客户ABC在他/她开户时要求提供他的个人信息
2）客户可以将钱存入他/她的账户
3）客户可以从他/她的账户中提取资金
4）如果账户余额低于100美元，则通知客户。（例如，当客户从应用程序的输入屏幕中选择选项3时，他/她被告知当时的帐户余额低于100美元，因此无法提取，除非他们存入更多的钱。）
5）应用程序应该能够维护客户的交易历史记录并显示交易历史记录（例如：当应用程序显示输入屏幕时，其中一个选项是 - 显示交易历史记录。选择此选项时在提示时显示一个数字，应用程序应显示一个Balance）
该程序的输入部分包括命令行中显示的4个选项：1。创建帐户2.存款3.提取资金。 4.显示交易历史

现在，我现在想要完成的是理解和识别：
1）在这样的程序中，Akka actors / Scala并发库的用例是什么？如果有任何可以作为此应用程序中的并发角色怎么办？
我可以最好地利用哪些Scala集合库？

Answer 1

我希望这能解决问题： http://alexminnaar.com/introduction-to-the-multithreading-problem-and-the-akka-actor-solution.html

注意：我刚注意到这篇文章已经过时了。我在2018年发帖回答。

Update1 :(链接说明，在评论中提到）

这是多种可能策略中的一种方法。

使用了两个演员

BankAccount - 管理余额

    object WireTransfer {

    case class Transfer(from: ActorRef, to: ActorRef, amount: BigInt)

    case object Done

    case object Failed

    }

    //actor implementing the actions of a wire transfer between two bank account actors
    class WireTransfer extends Actor {

    import WireTransfer._

    def receive = LoggingReceive {
    //If Transfer message is received, send withdraw message to 'from' and wait for reply
    case Transfer(from, to, amount) =>
    from ! BankAccount.Withdraw(amount)
    context.become(awaitFrom(to, amount, sender))
    }

    //If Withdraw was successful, send deposit to other bank account actor, or else give them a failure message
    def awaitFrom(to: ActorRef, amount: BigInt, customer: ActorRef): Receive = LoggingReceive {
    case BankAccount.Done =>
    to ! BankAccount.Deposit(amount)
    context.become(awaitTo(customer))
    case BankAccount.Failed =>
    customer ! Failed
    context.stop(self)
    }

    //If deposit was successful, send 'Done' to original actor that sent Transfer message
    def awaitTo(customer: ActorRef): Receive = LoggingReceive {
    case BankAccount.Done =>
    customer ! Done
    context.stop(self)
    }
    }

WireTransfer - 将余额从一个帐户转移到另一个帐户。

    object WireTransfer {

    case class Transfer(from: ActorRef, to: ActorRef, amount: BigInt)

    case object Done

    case object Failed

    }

    //actor implementing the actions of a wire transfer between two bank account actors
    class WireTransfer extends Actor {

    import WireTransfer._

    def receive = LoggingReceive {
    //If Transfer message is received, send withdraw message to 'from' and wait for reply
    case Transfer(from, to, amount) =>
    from ! BankAccount.Withdraw(amount)
    context.become(awaitFrom(to, amount, sender))
    }

    //If Withdraw was successful, send deposit to other bank account actor, or else give them a failure message
    def awaitFrom(to: ActorRef, amount: BigInt, customer: ActorRef): Receive = LoggingReceive {
    case BankAccount.Done =>
    to ! BankAccount.Deposit(amount)
    context.become(awaitTo(customer))
    case BankAccount.Failed =>
    customer ! Failed
    context.stop(self)
    }

    //If deposit was successful, send 'Done' to original actor that sent Transfer message
    def awaitTo(customer: ActorRef): Receive = LoggingReceive {
    case BankAccount.Done =>
    customer ! Done
    context.stop(self)
    }
    }

SavingsBankAccount程序中Scala的Actors的用例

1 个答案: