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

This example Play Framework source code file (JavaHelpers.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

a, b, concurrent, cookie, core, javahelpers, jcontext, jcookie, jrequest, lib, library, partialfunction, play, play framework, requestheader, string

The JavaHelpers.scala Play Framework example source code

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

import play.mvc.{ Result => JResult }
import play.mvc.Http.{ Context => JContext, Request => JRequest, Cookies => JCookies, Cookie => JCookie }

import play.libs.F
import scala.concurrent.Future
import play.api.libs.iteratee.Execution.trampoline

class EitherToFEither[A, B]() extends play.libs.F.Function[Either[A, B], play.libs.F.Either[A, B]] {

  def apply(e: Either[A, B]): play.libs.F.Either[A, B] = e.fold(play.libs.F.Either.Left(_), play.libs.F.Either.Right(_))

}

/**
 *
 * provides helper methods that manage java to scala Result and scala to java Context
 * creation
 */
trait JavaHelpers {
  import collection.JavaConverters._
  import play.api.mvc._
  import play.mvc.Http.RequestBody

  /**
   * creates a scala result from java context and result objects
   * @param javaContext
   * @param javaResult
   */
  def createResult(javaContext: JContext, javaResult: JResult): Result = {
    val wResult = javaResult.toScala.withHeaders(javaContext.response.getHeaders.asScala.toSeq: _*)
      .withCookies(javaContext.response.cookies.asScala.toSeq map { c =>
        Cookie(c.name, c.value,
          if (c.maxAge == null) None else Some(c.maxAge), c.path, Option(c.domain), c.secure, c.httpOnly)
      }: _*)

    if (javaContext.session.isDirty && javaContext.flash.isDirty) {
      wResult.withSession(Session(javaContext.session.asScala.toMap)).flashing(Flash(javaContext.flash.asScala.toMap))
    } else {
      if (javaContext.session.isDirty) {
        wResult.withSession(Session(javaContext.session.asScala.toMap))
      } else {
        if (javaContext.flash.isDirty) {
          wResult.flashing(Flash(javaContext.flash.asScala.toMap))
        } else {
          wResult
        }
      }
    }
  }

  /**
   * creates a java request (with an empty body) from a scala RequestHeader
   * @param request incoming requestHeader
   */
  def createJavaRequest(req: RequestHeader): JRequest = {
    new JRequest {

      def uri = req.uri

      def method = req.method

      def version = req.version

      def remoteAddress = req.remoteAddress

      def secure = req.secure

      def host = req.host

      def path = req.path

      def body = null

      def headers = req.headers.toMap.map(e => e._1 -> e._2.toArray).asJava

      def acceptLanguages = req.acceptLanguages.map(new play.i18n.Lang(_)).asJava

      def queryString = {
        req.queryString.mapValues(_.toArray).asJava
      }

      def acceptedTypes = req.acceptedTypes.asJava

      def accepts(mediaType: String) = req.accepts(mediaType)

      def cookies = new JCookies {
        def get(name: String): JCookie = {
          req.cookies.get(name).map(makeJavaCookie).orNull
        }

        private def makeJavaCookie(cookie: Cookie): JCookie = {
          new JCookie(cookie.name,
            cookie.value,
            cookie.maxAge.map(i => new Integer(i)).orNull,
            cookie.path,
            cookie.domain.orNull,
            cookie.secure,
            cookie.httpOnly)
        }

        def iterator: java.util.Iterator[JCookie] = {
          req.cookies.toIterator.map(makeJavaCookie).asJava
        }
      }

      override def toString = req.toString

    }
  }

  /**
   * creates a java context from a scala RequestHeader
   * @param req
   */
  def createJavaContext(req: RequestHeader): JContext = {
    new JContext(
      req.id,
      req,
      createJavaRequest(req),
      req.session.data.asJava,
      req.flash.data.asJava,
      req.tags.mapValues(_.asInstanceOf[AnyRef]).asJava
    )
  }

  /**
   * creates a java context from a scala Request[RequestBody]
   * @param req
   */
  def createJavaContext(req: Request[RequestBody]): JContext = {
    new JContext(req.id, req, new JRequest {

      def uri = req.uri

      def method = req.method

      def version = req.version

      def remoteAddress = req.remoteAddress

      def secure = req.secure

      def host = req.host

      def path = req.path

      def body = req.body

      def headers = req.headers.toMap.map(e => e._1 -> e._2.toArray).asJava

      def acceptLanguages = req.acceptLanguages.map(new play.i18n.Lang(_)).asJava

      def acceptedTypes = req.acceptedTypes.asJava

      def accepts(mediaType: String) = req.accepts(mediaType)

      def queryString = {
        req.queryString.mapValues(_.toArray).asJava
      }

      def cookies = new JCookies {
        def get(name: String): JCookie = {
          req.cookies.get(name).map(makeJavaCookie).orNull
        }

        private def makeJavaCookie(cookie: Cookie): JCookie = {
          new JCookie(cookie.name,
            cookie.value,
            cookie.maxAge.map(i => new Integer(i)).orNull,
            cookie.path,
            cookie.domain.orNull,
            cookie.secure,
            cookie.httpOnly)
        }

        def iterator: java.util.Iterator[JCookie] = {
          req.cookies.toIterator.map(makeJavaCookie).asJava
        }
      }

      override def toString = req.toString

    },
      req.session.data.asJava,
      req.flash.data.asJava,
      req.tags.mapValues(_.asInstanceOf[AnyRef]).asJava)
  }

  /**
   * Invoke the given function with the right context set, converting the scala request to a
   * Java request, and converting the resulting Java result to a Scala result, before returning
   * it.
   *
   * This is intended for use by methods in the JavaGlobalSettingsAdapter, which need to be handled
   * like Java actions, but are not Java actions.
   *
   * @param request The request
   * @param f The function to invoke
   * @return The result
   */
  def invokeWithContext(request: RequestHeader, f: JRequest => Option[F.Promise[JResult]]): Option[Future[Result]] = {
    val javaContext = createJavaContext(request)
    try {
      JContext.current.set(javaContext)
      f(javaContext.request()).map(_.wrapped.map(createResult(javaContext, _))(trampoline))
    } finally {
      JContext.current.remove()
    }
  }

  /**
   * Creates a partial function from a Java function
   */
  def toPartialFunction[A, B](f: F.Function[A, B]): PartialFunction[A, B] = new PartialFunction[A, B] {
    def apply(a: A) = f.apply(a)
    def isDefinedAt(x: A) = true
  }

}
object JavaHelpers extends JavaHelpers