Object-Business Process Mapping Frameworks: Abstractions, Architecture, and Implementation (EDOC 2014)

The integration between enterprise architectures and Business Process Management Systems (BPMS) is currently based on low-level programming interfaces that expose accidental complexities typical of process implementations. This paper describes an approach for integrating software architectures and BPMSs, based on mapping frameworks. Our inspiration are the Object-Relational Mapping (ORM) frameworks widely used to shield information systems from low-level structures exposed by relational database systems. The paper describes the central abstractions that should be provided by Object–Business Process Mapping Frameworks (OBPM). We also propose a reference architecture for implementing OBPMs and a concrete OBPM implementation, called NextFlow. We evaluated our approach by comparing two implementations of the same system, one using NextFlow and another using the native API supported by jBPM, a popular BPMS. By using NextFlow, we achieved a reduction of 30% in terms of lines of code, 35% in terms of number of classes, and 90% in terms of import statements, when implementing this system.

Transcript

1. Object–Business Process Mapping Frameworks: Abstractions, Architecture, and Implementation Rógel Garcia de Oliveira Marco Túlio Valente {rogelgarcia,mtov}@dcc.ufmg.br APPLIED SOFTWARE ENGINEERING RESEARCH GROUP
2. 1. Overview 2. Abstractions 3. Architecture 4. Implementation 5. Evaluation 6. Conclusion Agenda EDOC, 2014 2
3. 1. Overview
4. Information System BPMS Overview • Proprietary library. Lock in BPMS tool. • API expose low-level abstractions. • High learning curve. Challenges EDOC, 2014 4
5. void createProcessAndExecuteTask() { StatefulKnowledgeSession ks = createJbpmSession(" loanprocess . jbpm "); WorkflowProcessInstance pi = (WorkflowProcessInstance) ks.startProcess("process"); WorkItemNodeInstance wi = getWorkItem(pi, "approve transaction"); TransactionInfo ti = executeApproveTransaction(ks, wi, 1000); } WorkItemNodeInstance getWorkItem(WorkflowProcessInstance pi, String nodeName) { for (NodeInstance nodeInstance : pi.getNodeInstances()) if (nodeInstance.getNode().getName().equals(nodeName)) return (WorkItemNodeInstance) nodeInstance; return null; } TransactionInfo executeApproveTransaction(StatefulKnowledgeSession kSession, WorkItemNodeInstance wi, int value) { TransactionInfo ti = Application.approveTransaction(value); Map<String, Object> results = new HashMap<String, Object>(); results.put("transactionInfo", ti); kSession.getWorkItemManager().completeWorkItem(wi.getNodeId(), results); return ti; } Example – jBPM API EDOC, 2014 5
6. Proposed Solution Information System BPMS Object-Business Process Mapping Analogous to ORM (e. g. Hibernate) EDOC, 2014 6
7. Objectives • Standard integration to various BPMSs • Decouple IS from proprietary BPMS APIs • Reduce accidental complexity EDOC, 2014 7
8. 2. Abstractions
9. Lifecycle Information System BPMS Object-Business Process Mapping 1 – Build the process 2 – Create the mapped interface 3 – Calls are intercepted and delegated to the BPMS EDOC, 2014 9
10. Lifecycle Information System BPMS 4 –Data is syncronized Object-Business Process Mapping Object-Business Process Mapping EDOC, 2014 10
11. Lifecycle Information System BPMS 5 – When a taks is executed, callbacks may be triggered in the information system Object-Business Process Mapping EDOC, 2014 11
12. Lifecycle Information System BPMS Object-Business Process Mapping EDOC, 2014 12
13. Modeling Business Processes with OO • Process – ID: bankLoanProcess EDOC, 2014 13
14. Mapped Interface @Process("bankLoanProcess") interface BankProcess { void approveTransaction(); } EDOC, 2014 14
15. Mapped Interface • Reveals process semantics • Accidental complexity is reduced • Independency of BPMS bankProcess.approveTransaction(); EDOC, 2014 15
16. Data • A process can have associated data – Process Dataset • Key-Value pairs – Process Attribute • Bank Loan Process – clientID Key Value clientID 456d EDOC, 2014 16
17. Process Dataset @Process("bankLoanProcess") interface BankProcess { void approveTransaction(); LoanData getLoanData(); } class LoanData { String clientID; //getter and setter omitted } bankProcess.getLoanData().getClientID(); EDOC, 2014 17
18. Callback • Allows BPMS to execute services in the Information System – Complementary to Mapped Interfaces • Tasks are represented by methods EDOC, 2014 18
19. Callback Class @Process("bankLoanProcess") class BankProcessCallback { void approveTransaction() { //extra behavior } } EDOC, 2014 19
20. Callback Class – Data access @Process("bankLoanProcess") class BankProcessCallback { LoanData loanData; void approveTransaction() { //extra behavior } } EDOC, 2014 20
21. 3. Architecture
22. Architecture BPMS Workflow Connectivity Information System Object-Workflow Mapping EDOC, 2014 22
23. Workflow Connectivity – SPI BPMS X WFC API WFC Client DRIVER X String url = "jwfc:bpmsX:processFiles“; Session s = WorkflowManager.connect(url); String p = getProtocol(url); // bpmsX Driver driver = getDriver(p); Session s = driver.connect(url); class DriverX implements Driver { String getProtocol(){return “bpmsX";} SessionX connect(String url){....} } EDOC, 2014 23
24. Workflow Object Mapping Information System maps BPMS delegates Workflow Connectivity uses Object-Workflow Mapping provides EDOC, 2014 24
25. Workflow Object Mapping @Process("bankLoanProcess") interface BankProcess { void approveTransaction(); } class BankProcessImpl$$ implements BankProcess { ProcessInstance pi; void approveTransaction() { pi.getActivityByName("approveTransaction") .complete(); } } EDOC, 2014 25
26. Workflow Object Mapping @Process("bankLoanProcess") interface BankProcess { void approveTransaction(); } class BankProcessImpl$$ implements BankProcess { ProcessInstance pi; void approveTransaction() { pi.getActivityByName("approveTransaction") .complete(); } } EDOC, 2014 26
27. 4. Implementation NextFlow
28. Example Configuration conf = new Configuration("jwfc:bpmsX:resources"); EDOC, 2014 28
29. Example Configuration conf = new Configuration("jwfc:bpmsX:resources"); conf.addCallbackClass(BankProcessCallback.class); EDOC, 2014 29
30. Example Configuration conf = new Configuration("jwfc:bpmsX:resources"); conf.addCallbackClass(BankProcessCallback.class); WorkflowObjectFactory factory = conf.createFactory(); EDOC, 2014 30
31. Example Configuration conf = new Configuration("jwfc:bpmsX:resources"); conf.addCallbackClass(BankProcessCallback.class); WorkflowObjectFactory factory = conf.createFactory(); BankProcess bp = factory.start(BankProcess.class); EDOC, 2014 31
32. Example Configuration conf = new Configuration("jwfc:bpmsX:resources"); conf.addCallbackClass(BankProcessCallback.class); WorkflowObjectFactory factory = conf.createFactory(); BankProcess bp = factory.start(BankProcess.class); bp.approveTransaction(); EDOC, 2014 32
33. 4. Evaluation
34. Charging System • Credit transfer system • Two implementations – jBPM (native library) – NextFlow (with jBPM driver) EDOC, 2014 34
35. Charging System EDOC, 2014 35
36. Starting a new process jBPM API StatefulKnowledgeSession kSession = ...; Map<String, Object> params = new HashMap<String, Object>(); params.put("manager", (JbpmPhoneProcessManager) this); ProcessInstance p = kSession.startProcess(PROCESS_ID, params); NextFlow WorkflowObjectFactory factory = ...; ChargingProcess p = factory.start(ChargingProcess.class); EDOC, 2014 36
37. Data manipulation jBPM API WorkflowProcessInstance process = node.getProcessInstance(); Integer value = (Integer) process.getVariable("value"); String to = (String) process.getVariable("to"); Integer credit = chargingManager.getCreditFor(to); boolean enoughCredit = credit >= value; process.setVariable("enoughCredit", enoughCredit); NextFlow Integer credit = chargingManager.getCreditFor(data.getTo()); data.setEnoughtCredit(credit >= data.getValue()); EDOC, 2014 37
38. Metrics NextFlow • LOC: 330 (-30%) • Classes/Interfaces: 11 (-35%) • Char Count: 12.921 (-50%) • API Imports: 6 (-90%) jBPM API • LOC: 475 • Classes/Interfaces: 17 • Char Count: 25.500 • API Imports: 63 EDOC, 2014 38
39. 5. Conclusion
40. Object-Business Process Mapping Framework • Less programming effort • Independency of BPMS • Reduction in accidental complexity • Process semantics is exposed EDOC, 2014 40
41. QUESTIONS? DANKE SCHÖN! www.nextflow.org