Why does the Java compiler not like primitive int as type for values in HashMap?
It’s fine with Integer, but not okay with int – Java generics only work with reference types, basically 🙁 Try this – although be aware it will box everything: HashMap<String,Integer> userName2ind = new HashMap<String,Integer>(); for (int i=0; i<=players.length; i++) { userName2ind.put(orderedUserNames[i],i+1); }