斯卡拉对象

-1

内的对象的序列环，我有以下案例类斯卡拉对象

case class BusinessInput(userId: String, name: String, location: Point, address: Option[String], phonenumber: Option[String], email: Option[String], hours: Seq[BusinessHoursInput])

而下面BusinessHours案例类：

case class BusinessHoursInput(weekDay: Int, startTime: Time, endTime: Time)

我使用光滑，我试图加BusinessInput的BusinessHours行添加到BusinessInput的小时字段中的每个BusinessHoursinput对象的数据库。我曾尝试以下：

_ <- for(businessHours <- businessInput.hours) BusinessHours += BusinessHoursRow(businessRow.businessId, businessHours.weekDay, businessHours.startTime, businessHours.endTime)

但我被困在下面的错误：

value map is not a member of Unit 
[error]  _ <- for(businessHours <- businessInput.hours) BusinessHours += BusinessHoursRow(businessRow.businessId, businessHours.weekDay, businessHours.startTime, businessHours.endTime) 
[error]       ^

编辑：

这里是我的回购的创造功能，在那里我第一次尝试插入一个BusinessRow对象，然后从该插入中获取自动增量的Id，并使用先前插入的业务对象的Business Id插入businessHours对象的列表。然后我想返回业务对象，我第一次插入：

def create(businessInput: BusinessInput): Future[BusinessRow] = db.run(for { 
    // We create a projection of just the Business Columns, since we're not inserting a value for the id column 
    businessRow <- (Business.map(b => (b.userId, b.name, b.location, b.address, b.phonenumber, b.email)) 
    // Now define it to return the id, because we want to know what id was generated for the Business 
    returning Business.map(_.businessId) 
    // And we define a transformation for the returned value, which combines our original parameters with the 
    // returned id 
    into((userIdAndBusiness, id) => BusinessRow(id, userIdAndBusiness._1, userIdAndBusiness._2, userIdAndBusiness._3, userIdAndBusiness._4, userIdAndBusiness._5, userIdAndBusiness._6)) 
    // And finally, insert the business into the database 
) +=(businessInput.userId, businessInput.name, businessInput.location, businessInput.address, businessInput.phonenumber, businessInput.email) 
// Insert a sequence of BusinessHours objects 
    _ = for(businessHours <- businessInput.hours) BusinessHours += BusinessHoursRow(businessRow.businessId, businessHours.weekDay, businessHours.startTime, businessHours.endTime) 

    } yield (businessRow) 
)

这里是打印出来的是什么时间场的样子：

hours -> Vector(ListMap(weekDay -> 1, startTime -> 07:00, endTime -> 10:00), ListMap(weekDay -> 2, startTime -> 07:00, endTime -> 10:00))

，现在我收到以下错误：

scala.collection.immutable.ListMap$Node cannot be cast to dao.BusinessHoursInput

来源

2017-08-25 john

我很困惑_ <-'，你想做什么？ – DanGordon

请首先看看[Scala collections doc]（https://docs.scala-lang.org/overviews/collections/overview.html），以及Scala哲学如何关于不变性（而不是像'+ = '）。 – cchantep

如果此行是对收益的理解里面，你需要第一<-更改为=。因为BusinessHours += ...返回Unit，而_ <-被拆成flatMap或map。您也可以将BusinessHours += ...放入yield。

来源

2017-08-25 15:00:27

问题是，您正在使用的理解翻译为map。并且地图需要将hours: Seq[BusinessHoursInput]转换为其他内容。在地图里面你这样做：BusinessHours += BusinessHoursRow(businessRow.businessId, businessHours.weekDay, businessHours.startTime, businessHours.endTime) 这个选项不会将hours转换成别的东西。它将BusinessHoursRow添加到BusinessHours并且该操作返回单位。

那么如何解决呢？

1）BusinessHours变换BusinessHoursInput到BusinessHoursRow，然后将其插入：

var businessHoursRows = businessInput.hours.map { businessHoursInput => 
    BusinessHoursRow(businessHoursInput.businessId, businessHoursInput.weekDay, 
    businessHoursInput.startTime, businessHoursInput.endTime) 
} 
BusinessHours ++= businessHoursRows

2）使用的foreach代替map：你如何与`启动代码

businessInput.hours.foreach { businessHoursInput => 
    businessHoursRows += BusinessHoursRow(businessHoursInput.businessId, businessHoursInput.weekDay, 
    businessHoursInput.startTime, businessHoursInput.endTime) 
}

来源

2017-08-25 15:19:56

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