public String checkAreaCollision(CuboidArea newarea, ClaimedResidence parentResidence) { Set<Entry<String, ClaimedResidence>> set = residences.entrySet(); for (Entry<String, ClaimedResidence> entry : set) { ClaimedResidence check = entry.getValue(); if (check != parentResidence && check.checkCollision(newarea)) { return entry.getKey(); } } return null; }