/**
* Add a type to the slice at a given position, possibly changing the endpoints of some descendant
* intervals.
*
* @param type the type to add to the slice
* @param position a type already in the slice before which the new type will be placed, <code>
* null</code> if the type should be placed at the end of the slice
* @param ancestors the new type's ancestors
* @return the event for the endpoint changes, though there might be none
*/
protected EndpointsChangedEvent add(Constant type, Constant position, Set<Constant> ancestors) {
EndpointsChangedEvent event = new EndpointsChangedEvent(this, type);
order.add(type, position);
int typeLambda = lambdas.get(position), positionLambda = typeLambda;
Set<Constant> reducedAncestors = new HashSet<Constant>(ancestors);
for (Map.Entry<Constant, Interval<Constant>> entry : descendentIntervals.entrySet()) {
Interval<Constant> value = entry.getValue();
if (reducedAncestors.remove(entry.getKey())) {
if (value.getMin() == position) {
++positionLambda;
value.setMin(type);
event.addMinChange(entry.getKey());
}
if (value.getMax() == position) {
++typeLambda;
}
} else if (value.getMax() == position) {
value.setMax(type);
event.addMaxChange(entry.getKey());
}
}
descendentIntervals.put(type, new Interval<Constant>(order, type, position));
for (Constant ancestor : reducedAncestors) {
descendentIntervals.put(ancestor, new Interval<Constant>(order, type, position));
}
lambdas.put(type, typeLambda);
lambdas.put(position, positionLambda);
return event;
}
/**
* Construct a slice with a single element.
*
* @param type the element of the new slice
* @param ancestors its ancestors
*/
public Slice(Constant type, Set<Constant> ancestors) {
order.add(type, null);
descendentIntervals.put(type, new Interval<Constant>(order, type, null));
for (Constant ancestor : ancestors) {
descendentIntervals.put(ancestor, new Interval<Constant>(order, type, null));
}
lambdas.put(type, 0);
lambdas.put(null, 0);
}