In Chapter 2, Service Invocation, Chapter 3, Variables, Data Manipulation, and Expressions, and Chapter 4, Conditions and Loops, we have implemented the book warehousing process, which selected the most appropriate bookstore in order to warehouse the books. It selected between four bookstores, BookstoreA, BookstoreB, AnotherBookstore, and VintageBookstore. The selection criteria included the stock quantity and the publishing date of a book.

In this chapter, we will build upon the example from Chapter 4, Conditions and Loops. However, the BookWarehousingBPEL process in this chapter will have to be asynchronous. In Chapter 4, Conditions and Loops, we were not familiar with asynchronous processes yet. Therefore, we implemented all processes as synchronous. In Chapter 5, Interaction Patterns in BPEL, you learned about asynchronous processes and invocation. In contrast to a synchronous process, an asynchronous BPEL process does not require the client (process...