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 

1. Overview 2. Abstractions 3. Architecture 4. Implementation 5. Evaluation 6. Conclusion Agenda EDOC, 2014 2 

1. Overview 

Information System BPMS Overview • Proprietary library. Lock in BPMS tool. • API expose low-level abstractions. • High learning curve. Challenges EDOC, 2014 4 

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 results = new HashMap(); results.put("transactionInfo", ti); kSession.getWorkItemManager().completeWorkItem(wi.getNodeId(), results); return ti; } Example – jBPM API EDOC, 2014 5 

Proposed Solution Information System BPMS Object-Business Process Mapping Analogous to ORM (e. g. Hibernate) EDOC, 2014 6 

Objectives • Standard integration to various BPMSs • Decouple IS from proprietary BPMS APIs • Reduce accidental complexity EDOC, 2014 7 

2. Abstractions 

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 

Lifecycle Information System BPMS 4 –Data is syncronized Object-Business Process Mapping Object-Business Process Mapping EDOC, 2014 10 

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 

Lifecycle Information System BPMS Object-Business Process Mapping EDOC, 2014 12 

Modeling Business Processes with OO • Process – ID: bankLoanProcess EDOC, 2014 13 

Mapped Interface @Process("bankLoanProcess") interface BankProcess { void approveTransaction(); } EDOC, 2014 14 

Mapped Interface • Reveals process semantics • Accidental complexity is reduced • Independency of BPMS bankProcess.approveTransaction(); EDOC, 2014 15 

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 

Process Dataset @Process("bankLoanProcess") interface BankProcess { void approveTransaction(); LoanData getLoanData(); } class LoanData { String clientID; //getter and setter omitted } bankProcess.getLoanData().getClientID(); EDOC, 2014 17 

Callback • Allows BPMS to execute services in the Information System – Complementary to Mapped Interfaces • Tasks are represented by methods EDOC, 2014 18 

Callback Class @Process("bankLoanProcess") class BankProcessCallback { void approveTransaction() { //extra behavior } } EDOC, 2014 19 

Callback Class – Data access @Process("bankLoanProcess") class BankProcessCallback { LoanData loanData; void approveTransaction() { //extra behavior } } EDOC, 2014 20 

3. Architecture 

Architecture BPMS Workflow Connectivity Information System Object-Workflow Mapping EDOC, 2014 22 

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 

Workflow Object Mapping Information System maps BPMS delegates Workflow Connectivity uses Object-Workflow Mapping provides EDOC, 2014 24 

Workflow Object Mapping @Process("bankLoanProcess") interface BankProcess { void approveTransaction(); } class BankProcessImpl$$ implements BankProcess { ProcessInstance pi; void approveTransaction() { pi.getActivityByName("approveTransaction") .complete(); } } EDOC, 2014 25 

Workflow Object Mapping @Process("bankLoanProcess") interface BankProcess { void approveTransaction(); } class BankProcessImpl$$ implements BankProcess { ProcessInstance pi; void approveTransaction() { pi.getActivityByName("approveTransaction") .complete(); } } EDOC, 2014 26 

4. Implementation NextFlow 

Example Configuration conf = new Configuration("jwfc:bpmsX:resources"); EDOC, 2014 28 

Example Configuration conf = new Configuration("jwfc:bpmsX:resources"); conf.addCallbackClass(BankProcessCallback.class); EDOC, 2014 29 

Example Configuration conf = new Configuration("jwfc:bpmsX:resources"); conf.addCallbackClass(BankProcessCallback.class); WorkflowObjectFactory factory = conf.createFactory(); EDOC, 2014 30 

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 

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 

4. Evaluation 

Charging System • Credit transfer system • Two implementations – jBPM (native library) – NextFlow (with jBPM driver) EDOC, 2014 34 

Charging System EDOC, 2014 35 

Starting a new process jBPM API StatefulKnowledgeSession kSession = ...; Map params = new HashMap(); params.put("manager", (JbpmPhoneProcessManager) this); ProcessInstance p = kSession.startProcess(PROCESS_ID, params); NextFlow WorkflowObjectFactory factory = ...; ChargingProcess p = factory.start(ChargingProcess.class); EDOC, 2014 36 

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 

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 

5. Conclusion 

Object-Business Process Mapping Framework • Less programming effort • Independency of BPMS • Reduction in accidental complexity • Process semantics is exposed EDOC, 2014 40 

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