public List<Define> reorderDefines(Collection<Define> defines) {
List<Define> reordered = new ArrayList<Define>(defines.size());
HashSet<Identifier> added = new HashSet<Identifier>(), all = new HashSet<Identifier>();
Map<String, Pair<Define, Set<Identifier>>> pending =
new HashMap<String, Pair<Define, Set<Identifier>>>();
for (Define define : defines) {
Set<Identifier> dependencies = new TreeSet<Identifier>();
computeVariablesDependencies(define.getValue(), dependencies);
all.add(ident(define.getName()));
if (dependencies.isEmpty()) {
reordered.add(define);
added.add(ident(define.getName()));
} else {
pending.put(define.getName(), new Pair<Define, Set<Identifier>>(define, dependencies));
}
}
boolean progressed;
do {
progressed = false;
for (Iterator<Map.Entry<String, Pair<Define, Set<Identifier>>>> it =
pending.entrySet().iterator();
it.hasNext(); ) {
Map.Entry<String, Pair<Define, Set<Identifier>>> e = it.next();
Set<Identifier> dependencies = e.getValue().getSecond();
String name = e.getKey();
boolean missesDep = false;
for (Identifier dependency : dependencies) {
if (!added.contains(dependency)) {
missesDep = true;
if (!all.contains(dependency)) {
it.remove();
all.remove(name);
}
break;
}
}
if (missesDep) continue;
it.remove();
reordered.add(e.getValue().getFirst());
added.add(ident(name));
progressed = true;
}
} while (!pending.isEmpty() && progressed);
return reordered;
}
