/**
* Retrieve the list of all source and target connections for the connection.
*
* @param set HashSet to add the connections to.
* @param connectionEditPart the connection edit part.
*/
private void getSourceAndTargetConnections(
HashSet set, org.eclipse.gef.ConnectionEditPart connectionEditPart) {
if (connectionEditPart == null || set == null) return;
for (Iterator i = connectionEditPart.getSourceConnections().iterator(); i.hasNext(); ) {
org.eclipse.gef.ConnectionEditPart next = (org.eclipse.gef.ConnectionEditPart) i.next();
Connection sourceConnection = (Connection) next.getFigure();
set.add(sourceConnection);
getSourceAndTargetConnections(set, next);
}
for (Iterator i = connectionEditPart.getTargetConnections().iterator(); i.hasNext(); ) {
org.eclipse.gef.ConnectionEditPart next = (org.eclipse.gef.ConnectionEditPart) i.next();
Connection targetConnection = (Connection) next.getFigure();
set.add(targetConnection);
getSourceAndTargetConnections(set, next);
}
}
private Collection<Shape> getConnectionFigures() {
EditPart host = getHost();
Collection<Shape> shapes = new ArrayList<Shape>();
if (host instanceof CompositeConnectionEditPart) {
Collection<ConnectionEditPart> editParts =
((CompositeConnectionEditPart) host).getEditParts();
for (ConnectionEditPart editPart : editParts) {
shapes.add((Shape) editPart.getFigure());
}
} else {
shapes.add((Shape) ((GraphicalEditPart) getHost()).getFigure());
}
return shapes;
}
/**
* Figure out if a cyclic dependency will arise if target connection edit part is connected to the
* source connection edit part.
*
* @param targetCEP the target connection edit part
* @param sourceCEP the source connection edit part
* @param checkSourceAndTargetEditParts check both the source and taret edit parts for cyclic
* dependencies
* @param doNotCheckSourceEditPart (if checkSourceAndTargetEditParts is false) check only the
* target edit part if true, otherwise check only the source edit part
* @return true if a cyclic dependency would be create when targetCEP and sourceCEP were to be
* connected, false otherwise.
*/
private boolean isCyclicConnectionRequest(
org.eclipse.gef.ConnectionEditPart targetCEP,
org.eclipse.gef.ConnectionEditPart sourceCEP,
boolean checkSourceAndTargetEditParts,
boolean doNotCheckSourceEditPart) {
if (targetCEP == null || sourceCEP == null) return false;
if (sourceCEP == targetCEP) return true;
// first, do a cyclic check on source and target connections
// of the source connection itself.
// (as every connection is also a node).
HashSet set = new HashSet();
getSourceAndTargetConnections(set, sourceCEP);
if (set.contains(targetCEP.getFigure())) return true;
// now do the cyclic check on the source and target of the source connection...
EditPart sourceEP = sourceCEP.getSource(), targetEP = sourceCEP.getTarget();
if ((sourceEP == targetCEP) || (targetEP == targetCEP)) {
return true;
} else {
if (!checkSourceAndTargetEditParts && doNotCheckSourceEditPart) {
// .
} else if (sourceEP instanceof org.eclipse.gef.ConnectionEditPart
&& isCyclicConnectionRequest(
targetCEP,
(org.eclipse.gef.ConnectionEditPart) sourceEP,
true,
doNotCheckSourceEditPart)) return true;
if (!checkSourceAndTargetEditParts && !doNotCheckSourceEditPart) {
// .
} else if (targetEP instanceof org.eclipse.gef.ConnectionEditPart
&& isCyclicConnectionRequest(
targetCEP,
(org.eclipse.gef.ConnectionEditPart) targetEP,
true,
doNotCheckSourceEditPart)) return true;
}
return false;
}