workflow, bpm and java

2005 JavaOneSM Conference | Session 7364

Workflow, BPM and Java

Tom Baeyens

Lead DeveloperJBoss

TS-7364

2005 JavaOneSM Conference | Session 7364 | 2

• Tom Baeyens• Founder and project lead of JBoss jBPM• Member of JCP expert groups

• JSR207 ‘Process Definition for Java’• JSR208 ‘Java Business Integration’

Speaker


Agenda

Missing link in Java• Workflow• Business Process Management (BPM)• Orchestration

Traditional ApproachGraph Oriented ProgrammingConclusion


After all the trouble to make Java fast...

we’re going toadd wait states


Workflow requirementsBPM requirements

Orchestration requirements

workflowsolutions BPM

solutions

orchestrationsolutions


Suspending Path of Execution

System A System B

?


Java’s Limitation

...sendMessageToSystemB();Response response = waitForResponseFromB();...

• Not persistable• No graphical representation


Graphical Representation

• Analyst draws graphs that include wait states• Technical solution enables common language• Analysts do not create software

• Iterative refinement• Developer adds technical details• Analyst looks at projected view


Agenda




Traditional Approach

• Define a set of constructs• That are the node-types in a graph• With a graphical representation• And a runtime behaviour• Set of constructs is process language


Traditional Problems

• Monolithic systems• Process language is never powerfull enough• No modelling freedom• Turns into visual programming


Agenda




Graph Oriented Programming

• Define a directed graph

to *arrivingTransitions

fromleavingTransitions

*Node Transition



• Define an executional model• A Token is a path of execution in a single system

System A System B

Token



• Define an executional model

Troot

Tshipping Tbilling

Token

children

parent

Node



• Define an executional model• A Signal is the trigger that resumes process execution

System A

Token

send message to System B

send a Signal to the Token


Creating the ProcessInstance

ProcessInstance pi =

new ProcessInstance(pd);

Token token = pi.getRootToken();

token.signal();

// put process instance and token

// in the persistent store

// fetch the token from

// the persistent store

Token token = ...;

token.signal();

e.g. web app

e.g. MDB


Graph Execution Algorithm

• Chain of Responsibility

Node+execute(Token)

+leave(Token,

Transition)

Transition

+take(Token)to

leavingTransitions

*

1


Graph Execution Algorithm

• Algorithm is aligned with transactions• Client’s thread is used for calculation• No reinvention• Existing Java API’s are leveraged

• e.g. JMS for asynchronous communication


Hiding Details with Actions



Token



GOP provides the meansto structure your software

around a graph


Agenda





• Simple API + chain of responsibility• replaces monolithic systems

• Inheriting from Node• gives ultimate process language power

• Adding ‘invisible’ Actions• give modelling freedom

• Process development cycle• replaces visual programming


Building Blocks

Java


TaskMgmt

Task User Interfaces

AsyncInvocation

Transport

BusinessIntelligence

BI User Interfases


Summary

• Java has limited support for wait states• Graph Oriented Programming extends Java with

the ability to suspend and resume executions• Graph Oriented Programming is a building block • Workflow, BPM and orchestration functionalities

can be built on top of it


Conclusion

• JBoss jBPM implements this technology• modular• with functional extensions

• Available as a POJO API in a plain .jar• Scales to enterprise

So you can stop writing home grown frameworks


Next Steps

• Visit• http://jbpm.org• http://jboss.com

• JBoss jBPM userguide• Chapter “Graph Oriented Programming”

• Get involved• http://jbpm.org/forums• http://jbpm.org/wiki

• JBoss jBPM Training• http://jbpm.org/training

2005 JavaOneSM Conference | Session XXXX | 30

Demo

2005 JavaOneSM Conference | Session XXXX | 31

Q&A

workflow, bpm and java

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