/**
* Try to delete all given primitives.
*
* <p>If a node is used by a way, it's removed from that way. If a node or a way is used by a
* relation, inform the user and do not delete.
*
* <p>If this would cause ways with less than 2 nodes to be created, delete these ways instead. If
* they are part of a relation, inform the user and do not delete.
*
* @param layer the {@link OsmDataLayer} in whose context the primitives are deleted
* @param selection the objects to delete.
* @param alsoDeleteNodesInWay <code>true</code> if nodes should be deleted as well
* @param silent set to true if the user should not be bugged with additional questions
* @return command a command to perform the deletions, or null if there is nothing to delete.
*/
public static Command delete(
OsmDataLayer layer,
Collection<? extends OsmPrimitive> selection,
boolean alsoDeleteNodesInWay,
boolean silent) {
if (selection == null || selection.isEmpty()) return null;
// Diamond operator does not work with Java 9 here
Set<OsmPrimitive> primitivesToDelete = new HashSet<OsmPrimitive>(selection);
Collection<Relation> relationsToDelete =
Utils.filteredCollection(primitivesToDelete, Relation.class);
if (!relationsToDelete.isEmpty() && !silent && !confirmRelationDeletion(relationsToDelete))
return null;
if (alsoDeleteNodesInWay) {
// delete untagged nodes only referenced by primitives in primitivesToDelete, too
Collection<Node> nodesToDelete = computeNodesToDelete(primitivesToDelete);
primitivesToDelete.addAll(nodesToDelete);
}
if (!silent
&& !checkAndConfirmOutlyingDelete(
primitivesToDelete, Utils.filteredCollection(primitivesToDelete, Way.class)))
return null;
Collection<Way> waysToBeChanged =
new HashSet<>(
OsmPrimitive.getFilteredSet(OsmPrimitive.getReferrer(primitivesToDelete), Way.class));
Collection<Command> cmds = new LinkedList<>();
for (Way w : waysToBeChanged) {
Way wnew = new Way(w);
wnew.removeNodes(OsmPrimitive.getFilteredSet(primitivesToDelete, Node.class));
if (wnew.getNodesCount() < 2) {
primitivesToDelete.add(w);
} else {
cmds.add(new ChangeNodesCommand(w, wnew.getNodes()));
}
}
// get a confirmation that the objects to delete can be removed from their parent relations
//
if (!silent) {
Set<RelationToChildReference> references =
RelationToChildReference.getRelationToChildReferences(primitivesToDelete);
Iterator<RelationToChildReference> it = references.iterator();
while (it.hasNext()) {
RelationToChildReference ref = it.next();
if (ref.getParent().isDeleted()) {
it.remove();
}
}
if (!references.isEmpty()) {
DeleteFromRelationConfirmationDialog dialog =
DeleteFromRelationConfirmationDialog.getInstance();
dialog.getModel().populate(references);
dialog.setVisible(true);
if (dialog.isCanceled()) return null;
}
}
// remove the objects from their parent relations
//
for (Relation cur :
OsmPrimitive.getFilteredSet(OsmPrimitive.getReferrer(primitivesToDelete), Relation.class)) {
Relation rel = new Relation(cur);
rel.removeMembersFor(primitivesToDelete);
cmds.add(new ChangeCommand(cur, rel));
}
// build the delete command
//
if (!primitivesToDelete.isEmpty()) {
cmds.add(new DeleteCommand(layer, primitivesToDelete));
}
return new SequenceCommand(tr("Delete"), cmds);
}
