As an example, you can look at the source code of the BPMN Modeler sample in <installdir>/jviews-diagrammer/samples/diagrammer/bpmnmodeler/src/bpmn/BPMNModeler.java.

In the BPMN Modeler, a BPMN diagram is viewed and edited in an IlvDiagrammer object. An IlvDiagrammer object is a Swing component that displays a graph of nodes and links.

The BPMN Modeler is derived from the IlvBPMNModeler class. It uses BPMN-specific interactors, palettes, and style sheet.