Databases Reference
In-Depth Information
Summary
In this chapter, we've gone beyond individual services and looked at how we can
use BPEL to quickly assemble these services into composite services. By using this
same approach, we can also implement end-to-end business processes or complete
composite applications (something we will do in the second section of this topic).
You may have also noticed that although BPEL provides a rich set of constructs for
describing the assembly of a set of existing services, it doesn't try to reinvent the
wheel where functionality is already provided by existing SOA standards. Rather,
it has been designed to it naturally with and leverage the existing XML and web
services specifications such as XML Schema, XPath, XSLT, and of course, WSDL,
and SOAP.
This chapter should have given you a solid introduction to the basic structure of
a BPEL process, its key constructs, and the difference between a synchronous and
asynchronous service. Building the examples will help to reinforce this as well as
give you an excellent grasp of how to use JDeveloper to build BPEL processes.
Even though this chapter will have given you a good introduction to BPEL, we haven't
yet looked at much of its advanced functionality such as its ability to handle long
running processes, its fault and exception management, and how it uses compensation
to undo events in the case of failures. These are areas we will cover in more detail in
later chapters of the topic.
