BPMPetriNet

The BPMPetriNet package provides a Petri net implementation for Business Process Modeling.

The package provides the following functionality:

• Several place/transition net implementations
  • Place/transition net
  • Data-driven net
• (Un)Marshalling place/transition nets (from) to pnml format
• Unfolding place/transition nets into an event structure
• Conditional evaluation of guards using expressions
• Commandline tool that generates place/transition net of given sizes

Structure

The package is structured as followed:

• eventstructure
• expression
• petrinet
  • interfaces
    • element
    • marking
    • net
  • ptnet
    • element
    • marking
  • ddnet
    • marking
• pnml.ptnet
  • jaxb
  • marshaller
• util

Usage

The package provides its core functionalities as follows:

PTNetUnmarshaller pnu = new PTNetUnmarshaller(file);            //Read the pnml file
Set<Net> pnset = pnu.getNets();                                 //Retrieve the different nets from the file
Net net = pnset.iterator().next();                              //Retrieve a pnml place/transition net

PlaceTransitionNet pn = new PlaceTransitionNet(net);            //Create the required net type from the pnml net

Place p1 = pn.addPlace("p1", "initial", 1);                     //Add the initial place with 1 token
Transition t1 = pn.addTransition("t1", "transition");           //Add a transition
Place p2 = pn.addPlace("p2", "sink");                           //Add the sink place

Arc a = pn.addArc("p1", "t1", 1);                               //Add an arc by name with weight 1
Arc a1 = pn.addArc(t1, p2);                                     //Add another arc with standard weight

Marking m = pn.getInitialMarking();                             //Retrieve the initial marking
Transition t = pn.getEnabledTransitions(m).iterator().next();   //Retrieve an enabled transition
Marking n = pn.fire(t, m);                                      //Fire the transition

PTNetMarshaller pnm = new PTNetMarshaller(pnset, file));        //Write the pnml file

Toolspecific BPM extensions of the pnml file format

The package extends the pnml format with two BPM specific xml blocks.

1) Process block

The process block is part of a net and allows for the specification of global process information on:

• groups,
• roles, and
• variables.

2) Task block

The task block is part of a transition and allows for the specification of:

• parent (i.e., the id of the group to which it may belong),
• actor (i.e., the id of the role performing the task),
• unitsoftime (i.e., an abstract unit of time it may take to fire the transition),
• guard (i.e., the Boolean expression that must hold to fire the transition),
• isTau (i.e., whether the transition is silent or not),
• subProcess (i.e., the id of a net that contains the sub-process linked to the transition), and
• script (i.e., a piece of JavaScript that simulates some execution of the transition for data-driven nets).

Implementing your own Petri net format

To use the unfolding functionality provided by this package and the verification functionality provided by the BPMVerification package with your custom net implementations, the following elements of the Petri net should implement a number of interfaces provided in nl.rug.ds.bpm.petrinet.interfaces.

Petri net:

• UnfoldableNet (for unfolding support)
• VerifiableNet (for verification support)
• VerifiableDataNet (for data driven verification support)

Marking:

• MarkingI
• ConditionalMarkingI (for conditional verification support)
• DataMarkingI (for data driven verification support)

Net elements:

• NodeI (superclass of place and transition)
• PlaceI
• TransitionI
• ArcI