   finalize: (params) ->
     throw new Error "Not implemented!"
 
+  ping: ->
+    throw new Error "Not implemented!"
+
   destroy: ->
     throw new Error "Not implemented!"
 

  addQueue: (queue) =>
    @totalSizeQueued += item.size or 0 for item in queue
    @queue = @queue.concat queue

  nextInQueue: =>
    return if @busy

      queue = @cryptoWorker.queue
      @cryptoWorker = new FallbackCryptoWorker @, @size, @onProgress, @chunkSize
      @cryptoWorker.addQueue queue

class BaseCryptoWorker
  constructor: (@instance, @size, @onProgress, @chunkSize) ->
