Essential Business Process Modeling

BPELJ

“Pure” BPEL, examined previously, emphasizes “programming in the large,” or the activity of defining the big steps of a process in a clean XML form. But a process that is

BPEL WISH LIST

As comprehensive as BPEL is, it can still be improved. The following standard enhancements would make BPEL more powerful and easier to code:

foreach

Include an activity that can iterate over a data set. (An example of iterating over a repeating XML element using a while loop and XPath is presented in the section "Implementing foreach.” earlier in this chapter.)

XML creation and update

Enhance the assign activity to support the construction of XML elements or documents. For example, build a reply message using data from a request message.

Lightweight subprocesses or macros

Provide a mechanism to factor out a chunk of code into a modular piece, and provide the ability to call that piece with parameters in a lightweight fashion.

More sophisticated correlation

In addition to basic correlation set matching, allow a message listener activity (receive, pick, eventHandler) to filter on an arbitrary Boolean condition written in XPath or XQuery. In the example at the beginning of this chapter, the kill claim event handler triggers only if the kill message has the same claim ID as the original claim request. Supporting more complex queries would be desirable; for example, allowing the kill only if the claim amount is less than $1,000; the claim has been active for less than two business days; and the claim is not ...