Publishing Engine Programmer's Guide > The Arbortext Publishing Engine Request Manager > Predefined Dynamic Components > Predefined Request Functions
  
Predefined Request Functions
A request function is a Java class that implements the interface com.arbortext.e3.E3RequestFunction. In particular, such an object must provide a method named execute that takes an HttpServletRequest object, which contains an HTTP request as a parameter, and returns an HTTP response (encoded as an HttpRequestResponse object).
You can extend the Arbortext PE Request Manager by writing either a request handler or a request function. Writing a request function is easier than writing a complete request handler. Consult Writing a Custom Request Handler and Writing a Custom Request Function for more information.
In the sections that follow, the HTTP request parameters follow the format for HTTP requests described in Web Clients and the HTTP Protocol. You can use the Arbortext Publishing Engine Testing HTML page to issue most of these request functions.