Publishing Engine Programmer's Guide > The Arbortext Publishing Engine Request Manager > Customizing the Arbortext PE Request Manager > Writing a Custom Notifier
  
Writing a Custom Notifier
To develop a Notifier object, you must create a Java class that implements the interface com.arbortext.e3.E3Notifier. In addition to the getId, init, destroy, and getStatus methods, a notifier must implement the method changeState.
The Arbortext Publishing Engine Request Handler calls the changeState method of every notifier, in the order defined in e3config.xml, each time a transaction changes state. The action that the notifier takes when its changeState method is called is entirely up to the notifier. The changeState has an oldState parameter (the previous state of the transaction) and a newState parameter (the new state of the transaction).
Unlike other Dynamic Components, where the cache manager, queue manager, request handler, or queue that accepts a request ends the iteration, the changeState method is called for every configured notifier.