Why use jBPM with Mule?
What is BPM and why would you use it with Mule?
BPM stands for Business Process Management and simplistically can be thought of as a system which automates business processes. Typically a BPM system will have a graphical interface which allows you to model your business processes visually so that a business analyst or other non-programmer can easily understand them and verify that they indeed reflect the reality of your business.
jBPM is arguably the best-of-breed open source software in this space and has a similar philosophy to Mule when it comes to valuing simplicity and functionality over adhering to cumbersome “standards” such as BPEL.
Mule ESB integrates with jBPM, allowing you to send/receive messages to/from a running process. A message from Mule can start or advance a process, the message can be used as a process variable, and a process can send messages to any endpoint in your Mule config.
So when might you consider using jBPM with your Mule application?
Mule has had integration with jBPM since around 1.3, but we have recently improved our support for Mule 3.0, including an upgrade to the latest major version of jBPM (4.3), much simplified configuration, and cleaner integration with Mule from your process definition, including custom process elements. For more information, refer to the Mule 3 documentation.
Process Definition Snippet using custom Mule elements
<!-- Request received from customer -->
<mule-receive name="incomingCustomerRequest"
endpoint="CustomerRequests" var="customerRequest">
<transition to="sendToCreditAgency" />
</mule-receive>
<!-- Send customer info. to credit agency -->
<mule-send name="sendToCreditAgency"
expr="#{customerRequest.customer}" endpoint="CreditAgency"
synchronous="false">
<transition to="waitForCreditAgency" />
</mule-send>
<!-- Wait for the customer's credit profile to arrive. -->
<mule-receive name="waitForCreditAgency"
endpoint="CreditProfiles" var="creditProfile">
<transition to="prepareLoanQuoteRequest" />
</mule-receive>
<!-- Send the request to one of three banks, depending on the loan
amount and customer credit info. -->
<decision name="sendToBanks">
<transition to="sendToBigBank">
<condition expr="#{customerRequest.loanAmount >= 20000}" />
<condition expr="#{creditProfile.creditHistory >= 24}" />
<condition expr="#{creditProfile.creditScore >= 5}" />
</transition>
<transition to="sendToMediumBank">
<condition expr="#{customerRequest.loanAmount >= 10000}" />
<condition expr="#{creditProfile.creditHistory >= 12}" />
<condition expr="#{creditProfile.creditScore >= 3}" />
</transition>
<transition to="sendToSmallBank">
<condition expr="#{creditProfile.creditHistory >= 6}" />
<condition expr="#{creditProfile.creditScore >= 1}" />
</transition>
<!-- If the credit info. doesn't meet minimum requirements based
on the loan amount, the loan is just denied. -->
<transition to="loanDenied" />
</decision>
<mule-send name="sendToBigBank" expr="#{loanRequest}"
endpoint="BigBank" var="loanQuote"
type="org.mule.example.loanbroker.messages.LoanQuote">
<transition to="sendCustomerResponse" />
</mule-send>
