+
+ // Initialize work queue (out-going, produced items)
+ $this->initWorkQueue();
+ }
+
+ /**
+ * Setter for out-going work queue
+ *
+ * @param $outgoingQueueInstance The out-going work queue instance
+ * @return void
+ */
+ private function setOutgoingQueueInstance (Stackable $outgoingQueueInstance) {
+ $this->outgoingQueueInstance = $outgoingQueueInstance;
+ }
+
+ /**
+ * Getter for out-going work queue
+ *
+ * @param $outgoingQueueInstance The out-going work queue instance
+ */
+ protected function getOutgoingQueueInstance () {
+ return $this->outgoingQueueInstance;