Orchestrations with BPEL

Abstract

In previous chapters, particularly in Chaps. 8 and 9, we have studied a wide range of constructs that can be used to design the flow of an orchestration. These constructs have been represented graphically by means of certain shapes, but more important than being able to represent them, it is fundamental to understand the concepts that underlie those constructs. For example, the use of an activating receive shape means that a new orchestration instance will be created when a certain message is received. As another example, the use of a correlation presumes that there is a set of messages which share some common data with exactly the same values (the correlation id). The use of certain shapes in an orchestration therefore requires a good understanding of the concepts that are embedded in those constructs. For example, a good knowledge of what compensation is and how it works is essential in order to use transactions in orchestrations, as explained in Sect. 9.4.