Downloading the Code

Overview

Enterprise JavaBeans (EJBs) require the ability to communicate between each other and the applications using them. The communication can involve sending something as simple as an integer or as complex as an entire Java object. To accomplish this communication, you must define a protocol—or more specifically, a wire protocol—that allows all types of information to be passed back and forth without developer intervention or complicated syntax.

The developers at Caucho looked at all of the options for a wire protocol when developing their EJB solution and determined that SOAP, CORBA-IIOP, and XML-RPC just didn't fit their goals for a protocol. However, those goals (summarized here) are outlined in the Burlap Web Service Protocol specification:

• It must serialize Java objects.

• It must support EJB.

• It must be fast, testable, and simple.

The Burlap Web Service Protocol is based on Simple Markup Language (SML), a subset of XML. In this chapter, we provide an overview of Burlap to give you an idea of how EJBs hosted in Resin are communicating with each other. In addition, we illustrate how you can use Burlap with independent applications.