Source
int byFeatureOrdering(String a, String b) {
int scoreA = 0;
int scoreB = 0;
if (featureOrder.containsKey(a)) scoreA = featureOrder[a];
if (featureOrder.containsKey(b)) scoreB = featureOrder[b];
if (scoreA < scoreB) return -1;
if (scoreA > scoreB) return 1;
return compareAsciiLowerCaseNatural(a, b);
}