please include function getOpt_cached. static Field findField2(O o, S field) { Class c = o.getClass(); HashMap map; synchronized(getOpt_cache) { map = getOpt_cache.get(c); if (map == null) map = getOpt_makeCache(c); } if (map == getOpt_special) { if (o instanceof Class) ret findField2_findStaticField((Class) o, field); } ret map.get(field); } static Field findField2_findStaticField(Class c, String field) { Class _c = c; do { for (Field f : _c.getDeclaredFields()) if (f.getName().equals(field) && (f.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0) return f; _c = _c.getSuperclass(); } while (_c != null); ret null; }