Lift Framework example source code file (Jetty6AsyncProvider.scala)

This example Lift Framework source code file (Jetty6AsyncProvider.scala) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Lift Framework tags/keywords

boolean, boolean, http, httprequest, in, jetty6asyncprovider, jetty6asyncprovider, liftresponse, liftresponse, liftrules, none, none, option, req, request, response, servlet, servletasyncprovider

The Lift Framework Jetty6AsyncProvider.scala source code

/*
 * Copyright 2010-2011 WorldWide Conferencing, LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package net.liftweb 
package http 
package provider 
package servlet 
package containers 

import javax.servlet.http.HttpServletRequest

import net.liftweb.common._
import net.liftweb.http._
import net.liftweb.http.provider._
import net.liftweb.http.provider.servlet._
import net.liftweb.util._
import Helpers._


object Jetty6AsyncProvider extends AsyncProviderMeta {
  private lazy val (hasContinuations_?,
                    contSupport,
                    getContinuation,
                    getObject,
                    setObject,
                    suspendMeth,
                    resumeMeth,
                    isPending) = {
    try {
      val cc = Class.forName("org.mortbay.util.ajax.ContinuationSupport")
      val meth = cc.getMethod("getContinuation", classOf[HttpServletRequest], classOf[AnyRef])
      val cci = Class.forName("org.mortbay.util.ajax.Continuation")
      val getObj = cci.getMethod("getObject")
      val setObj = cci.getMethod("setObject", classOf[AnyRef])
      val suspend = cci.getMethod("suspend", java.lang.Long.TYPE)
      val resume = cci.getMethod("resume")
      val isPending = cci.getMethod("isPending")
      (true, (cc), (meth), (getObj), (setObj), (suspend), resume, isPending)
    } catch {
      case e => (false, null, null, null, null, null, null, null)
    }
  }

  def suspendResumeSupport_? : Boolean = hasContinuations_?

  /**
   * return a function that vends the ServletAsyncProvider
   */
  def providerFunction: Box[HTTPRequest => ServletAsyncProvider] =
    Full(req => new Jetty6AsyncProvider(req)).
  filter(i => suspendResumeSupport_?)


}

/**
 * Jetty6AsyncProvider
 *
 * Implemented by using Jetty 6 Continuation API
 *
 */
class Jetty6AsyncProvider(req: HTTPRequest) extends ServletAsyncProvider with Loggable {

  import Jetty6AsyncProvider._

  private lazy val servletReq = (req.asInstanceOf[HTTPRequestServlet]).req

  def suspendResumeSupport_? : Boolean = hasContinuations_?

  def resumeInfo: Option[(Req, LiftResponse)] =
    if (!hasContinuations_?) None
    else if (Props.inGAE) None
    else {
      val cont = getContinuation.invoke(contSupport, servletReq, LiftRules)
      val ret = getObject.invoke(cont)
      try {
        setObject.invoke(cont, null)
        ret match {
          case (r: Req, lr: LiftResponse) => Some(r -> lr)
          case _ => None
        }
      }
      catch {
        case e: Exception => None
      }
   }


  def suspend(timeout: Long): RetryState.Value = {
    try {
      val cont = getContinuation.invoke(contSupport, servletReq, LiftRules)
      logger.trace("About to suspend continuation")
      val b = suspendMeth.invoke(cont, new java.lang.Long(timeout)).asInstanceOf[Boolean]
      if (!b) RetryState.TIMED_OUT else RetryState.RESUMED
    } catch {
      case e: java.lang.reflect.InvocationTargetException if e.getCause.getClass.getName.endsWith("RetryRequest") =>
        throw e.getCause
    }
  }

  def resume(what: (Req, LiftResponse)): Boolean = {
    val cont = getContinuation.invoke(contSupport, servletReq, LiftRules)
    cont.synchronized {
      logger.trace("In resume on Jetty 6")
      val pending = isPending.invoke(cont).asInstanceOf[Boolean]
      if (pending) {
       setObject.invoke(cont, what)
       resumeMeth.invoke(cont)
      }
      pending
    }
  }
}