Book Image

BPEL and Java Cookbook

By : Jurij Laznik
Book Image

BPEL and Java Cookbook

By: Jurij Laznik

Overview of this book

The Business Process Execution Language (BPEL) has become the de-facto standard for orchestrating web services. BPEL and web services are both clamped into Service-oriented Architecture (SOA). Development of efficient SOA composites too often requires usage of other technologies or languages, like Java. This Cookbook explains through the use of examples how to efficiently integrate BPEL with custom Java functionality.If you need to use BPEL programming to develop web services in SOA development, this book is for you.BPEL and Java Cookbook will show you how to efficiently integrate custom Java functionality into BPEL processes. Based on practical examples, this book shows you the solutions to a number of issues developers come across when designing SOA composite applications. The integration between the two technologies is shown two-fold; the book focuses on the ways that Java utilizes the BPEL and vice-versa.With this book, you will take a journey through a number of recipes that solve particular problems with developing SOA composite applications. Each chapter works on a different set of recipes in a specific area. The recipes cover the whole lifecycle of developing SOA composites: from specification, through design, testing and deployment. BPEL and Java Cookbook starts off with recipes that cover initiation of BPEL from Java and vice-versa. It then moves on to logging and tracing facilities, validation and transformation of BPEL servers, embedding of third-party Java libraries into BPEL. It also covers manipulation with variables in BPEL different techniques of Java code wrapping for web service usage and utilization of XML fa?ßades. After reading BPEL and Java Cookbook you will be able to circumvent many of the issues that developers experience during SOA composite application development.  
Table of Contents (18 chapters)
BPEL and Java Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Defining local variables in a BPEL process


Too many global variables can cause a lot of confusion and can also consume a lot of memory. Hence, we define global variables only when we need data to be available all the time. For that reason, we omit the scope variable visibility by defining them locally. By doing this, we also achieve higher clarity of the BPEL process source code. This recipe will explain the difference between global and local variables in the BPEL processes.

Getting ready

For this recipe, we will extend the BPEL process from the previous recipe. Note that the variables are tightly related to the scope, which encloses them. We will add a scope to our BPEL process and reuse the same web service. The BPEL process outlook is as shown in the following screenshot:

How to do it…

To define a local variable in a BPEL process, we perform the following steps:

  1. We define a local variable by pressing the (X) icon in the left-side toolbar of the scope. The dialog opens global . However, this...