Play Framework/Scala example source code file (TemplateMagicForJava.scala)

This example Play Framework source code file (TemplateMagicForJava.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Play Framework (and Scala) source code examples by using tags.

All credit for the original source code belongs to Play Framework; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Play Framework tags/keywords

api, core, mvc, none, nonfatal, option, play, play framework, playmagicforjava, string, utilities

The TemplateMagicForJava.scala Play Framework example source code

/*
 * Copyright (C) 2009-2013 Typesafe Inc. <http://www.typesafe.com>
 */
package play.core.j

import play.api.mvc._

import scala.util.control.NonFatal

/** Defines a magic helper for Play templates in a Java context. */
object PlayMagicForJava {

  import scala.collection.JavaConverters._
  import scala.language.implicitConversions

  /** Transforms a Play Java `Option` to a proper Scala `Option`. */
  implicit def javaOptionToScala[T](x: play.libs.F.Option[T]): Option[T] = x match {
    case x: play.libs.F.Some[_] => Some(x.get)
    case x: play.libs.F.None[_] => None
  }

  implicit def implicitJavaLang: play.api.i18n.Lang = {
    try {
      play.mvc.Http.Context.Implicit.lang.asInstanceOf[play.api.i18n.Lang]
    } catch {
      case NonFatal(_) => play.api.i18n.Lang.defaultLang
    }
  }

  /**
   * Implicit conversion of a Play Java form `Field` to a proper Scala form `Field`.
   */
  implicit def javaFieldtoScalaField(jField: play.data.Form.Field): play.api.data.Field = {

    new play.api.data.Field(
      null,
      jField.name,
      jField.constraints.asScala.map { jT =>
        jT._1 -> jT._2.asScala
      },
      Option(jField.format).map(f => f._1 -> f._2.asScala),
      jField.errors.asScala.map { jE =>
        play.api.data.FormError(
          jE.key,
          jE.messages.asScala,
          jE.arguments.asScala)
      },
      Option(jField.value)) {

      override def apply(key: String) = {
        javaFieldtoScalaField(jField.sub(key))
      }

      override lazy val indexes = jField.indexes.asScala.toSeq.map(_.toInt)

    }
  }

  implicit def requestHeader: play.api.mvc.RequestHeader = {
    play.mvc.Http.Context.Implicit.ctx._requestHeader
  }

}