How to make a CaseInsensitiveConcurrentMap?

Question

How can I implement

class CaseInsensitiveConcurrentMap<V> implements ConcurrentMap<String , V>

which works just like ConcurrentHashMap<String , V> except that the keys are compared case-insensitively? The keys should not be converted to lowercase or uppercase.

Note that Collections.synchronizedMap(new TreeMap<String, new MyCaseInsensitiveComparator()) is no solution as it allows no concurrency and misses the additional methods.

Creating a String-like class with case-insensitive equals and hashCode is no option either, since the map has to be passed to methods expecting strings as keys.

Answer 1

Have you tried

ConcurrentMap<String, Object> map = 
    new ConcurrentSkipListMap<String, Object>(
        String.CASE_INSENSITIVE_ORDER);