Book Image

WS-BPEL 2.0 Beginner's Guide

Book Image

WS-BPEL 2.0 Beginner's Guide

Overview of this book

Table of Contents (19 chapters)
WS-BPEL 2.0 Beginner's Guide
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Parallel service invocation


BPEL also supports parallel service invocation. In our example, we have invoked Bookstore A and Bookstore B sequentially. This way, we need to wait for the response from the first service and then for the response from the second service. If these services take longer to execute, the response times will be added together. If we invoke both services in parallel, we only need to wait for the duration of the longer-lasting call, as shown in the following screenshot:

Note

BPEL has several possibilities for parallel flows, which will be described in detail in Chapter 8, Dynamic Parallel Invocations. Here, we present the basic parallel service invocation using the <flow> activity.

To invoke services in parallel, or to perform any other activities in parallel, we can use the <flow> activity. Within the <flow> activity, we can nest an arbitrary number of flows, and all will execute in parallel. Let's try and modify our example so that Bookstore A and B...