我在Scala中使用JSON4S以JSON格式获取我的POJO类的toString(),如下所示。
//JSON related libraries
import org.json4s.{DefaultFormats, Formats}
//JSON handling support from Scalatra
import org.scalatra.json._
// JSON library for converting the POJO toString as Json
import org.json4s.native.Json
class Customer(val id:Int, var firstName:String, var lastName:String) {
println("Customer - Constructor BEGIN .... ")
def this(firstName:String, lastName:String) {
this(Customer.inc, firstName, lastName)
}
//override def toString = s"Customer [Id=$id, FirstName=$firstName, LastName=$lastName]"
override def toString = Json(DefaultFormats).write(this)
println("Customer - Constructor END .... ")
}
但是,当我使用实例测试时,元素的顺序会失真如下。
{
"firstName": "Raghavan",
"id": 1,
"lastName": "Muthu"
}
我真正想要的是
{
"id": 1,
"firstName": "Raghavan",
"lastName": "Muthu"
}
我怎样才能做到这一点?