scala - 是否有类似适用于Scala的AutoMapper？

Question

我一直在寻找一些用于映射对象-对象的Scala流利API，类似于AutoMapper。
Scala中有这样的工具吗？

Answer 1

我认为Scala中不需要诸如AutoMapper之类的东西，因为如果您使用惯用的Scala模型，则更容易编写和操作，并且您可以使用隐式转换轻松地定义自动展平/投影。

例如，这是AutoMapper flattening example的Scala中的等效项：

// The full model

case class Order( customer: Customer, items: List[OrderLineItem]=List()) {
  def addItem( product: Product, quantity: Int ) = 
    copy( items = OrderLineItem(product,quantity)::items )
  def total = items.foldLeft(0.0){ _ + _.total }
}

case class Product( name: String, price: Double )

case class OrderLineItem( product: Product, quantity: Int ) {
  def total = quantity * product.price
}

case class Customer( name: String )

case class OrderDto( customerName: String, total: Double )


// The flattening conversion

object Mappings {
  implicit def order2OrderDto( order: Order ) = 
    OrderDto( order.customer.name, order.total )
}


//A working example

import Mappings._

val customer =  Customer( "George Costanza" )
val bosco = Product( "Bosco", 4.99 )
val order = Order( customer ).addItem( bosco, 15 )

val dto: OrderDto = order // automatic conversion at compile-time !

println( dto ) // prints: OrderDto(George Costanza,74.85000000000001)

PS：我不应该将Double用作金额...