List<ContainerShape> top = new ArrayList<ContainerShape>();
List<ContainerShape> bottom = new ArrayList<ContainerShape>();
if (participantBands.size() == 1) {
BPMNShape bpmnShape = BusinessObjectUtil.getFirstElementOfType(participantBands.get(0), BPMNShape.class);
ParticipantBandKind bandKind = bpmnShape.getParticipantBandKind();
if (bandKind == ParticipantBandKind.TOP_INITIATING || bandKind == ParticipantBandKind.TOP_NON_INITIATING) {
top.add(participantBands.get(0));
} else if (bandKind == ParticipantBandKind.BOTTOM_INITIATING
|| bandKind == ParticipantBandKind.BOTTOM_NON_INITIATING) {
bottom.add(participantBands.get(0));