@Override
void pushNotsDown() {
if (!bool) { // ONLY push down if this is a "not"
bool = true;
switch (conjunction) {
case AND:
conjunction = Conjunction.OR;
break;
case OR:
conjunction = Conjunction.AND;
break;
}
for (Node node : nodes) {
node.invert();
}
}
for (Node node : nodes) {
node.pushNotsDown();
}
}
@Override
Node simplify() {
boolean simplifyAgain;
do {
simplifyAgain = false;
// first, simplify our sub-ops...
List<Node> simplified = new ArrayList<Node>();
for (Node node : nodes) {
simplified.add(node.simplify());
}
nodes = simplified;
// now, see if any of our subops can be trivially combined with us
List<Node> combined = new ArrayList<Node>();
for (Node node : nodes) {
if (node instanceof OperatorNode) {
OperatorNode opnode = (OperatorNode) node;
if (opnode.conjunction == conjunction && opnode.bool) {
simplifyAgain = true;
for (Node child : opnode.nodes) {
combined.add(child);
}
continue;
}
}
combined.add(node);
}
nodes = combined;
} while (simplifyAgain);
if (nodes.isEmpty()) {
return null;
} else if (nodes.size() == 1) {
Node node = nodes.get(0);
if (!bool) {
node.invert();
}
return node;
}
return this;
}
