/*
 * =========================================================================================
 * Copyright © 2013-2014 the kamon project <http://kamon.io/>
 *
 * 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 testkit

import java.util.concurrent.ConcurrentHashMap

import akka.actor.{ ActorSystem, Extension, ExtensionId }

object AkkaExtensionSwap {
  def swap(system: ActorSystem, key: ExtensionId[_], value: Extension): Unit = {
    val extensionsField = system.getClass.getDeclaredField("extensions")
    extensionsField.setAccessible(true)

    val extensions = extensionsField.get(system).asInstanceOf[ConcurrentHashMap[ExtensionId[_], AnyRef]]
    extensions.put(key, value)
  }
}