BPEL V2.0 is a powerful language intended to help in development of huge,
complex applications consisting of a lot of other components and Web
services. The BPEL vendor-neutral specification was developed by OASIS
to specify business processes as a set of interactions between Web
services. BPEL allows you to describe long-running workflows using
graphical editors to present workflows on human-friendly diagrams.
The Apache Foundation calls its implementation of the Web Services
Business Process Execution Language (WS-BPEL) V2.0 the Orchestration
Director Engine (ODE). ODE executes WS-BPEL processes, which are capable
of communicating with Web services, sending and receiving messages, etc.
The Eclipse BPEL project is a related open source project that provides
an Eclipse plug-in for the visual development of WS-BPEL V2.0 processes.
This article examines ODE V1.1 and the Eclipse BPEL project milestone M3,
describing how to create your own BPEL process and integrate it into
your application. Summary from the ODE web site: "WS-BPEL is an XML-based
language defining several constructs to write business processes. It
defines a set of basic control structures like conditions or loops as
well as elements to invoke web services and receive messages from
services. It relies on WSDL to express web services interfaces. Message
structures can be manipulated, assigning parts or the whole of them to
variables that can in turn be used to send other messages. Apache ODE
(Orchestration Director Engine) executes business processes written
following the WS-BPEL standard. It talks to web services, sending and
receiving messages, handling data manipulation and error recovery as
described by your process definition. It supports both long and short
living process executions to orchestrate all the services that are part
of your application."