/** Dump a set to a string for debug. */
private static String dumpSet(Set<GraphNode> s) {
StringBuffer sb = new StringBuffer();
sb.append("{");
boolean started = false;
for (GraphNode value : s) {
if (started) {
sb.append(", ");
} else {
started = true;
}
sb.append(value.toString());
}
sb.append("}");
return sb.toString();
}
