QueryStringBindable #playframewok #scala Require a "play clean" to import the object in routes. Check target/scala-2.10/src_managed/main/routes_routing.scala to see if the import is present.

Build.scala

import sbt._
import Keys._
import Path._
import play.Project._

object ApplicationBuild extends Build {

  val appName         = "scala-test"
  val appVersion      = "1.0-SNAPSHOT"

  val appDependencies = Seq(
    jdbc,
    "mysql" % "mysql-connector-java" % "5.1.18",
    "com.typesafe.slick" % "slick_2.10" % "1.0.0",
    "joda-time" % "joda-time" % "2.0"

  )


  val main = play.Project(appName, appVersion, appDependencies).settings(
    // Add your own project settings here
    resolvers += "Local Maven Repository" at "file://" + Path.userHome.absolutePath + "/.m2/repository",
    routesImport += "services.QueryBinders.localDateBinder"
  )

}

routes

GET     /someUrl    controllers.SomeController.get(startDate: org.joda.time.LocalDate ?= null, endDate: org.joda.time.LocalDate ?= null)

services.QueryBinders.scala

package services

import org.joda.time.LocalDate
import play.api.mvc.QueryStringBindable
import org.joda.time.format.{DateTimeFormat, DateTimeFormatter}

object QueryBinders extends {

  implicit def localDateBinder: QueryStringBindable[LocalDate] = new QueryStringBindable[LocalDate]{

    val dateTimeFormatter: DateTimeFormatter = DateTimeFormat.forPattern("yyyy-MM-dd");

    def bind(key: String, params: Map[String, Seq[String]]): Option[Either[String, LocalDate]] = {
      val dateString: Option[Seq[String]] = params.get(key)
      try {
        Some(Right(dateTimeFormatter.parseLocalDate(dateString.get.head)))
      } catch {
        case e: IllegalArgumentException => Option(Left(dateString.get.head))
      }
    }

    def unbind(key: String, value: LocalDate): String = {
      dateTimeFormatter.print(value)
    }
  }
}