@Override
        public boolean equals(final Object obj) {
            if (obj == null) {
                return false;
            }
            if (!(obj instanceof CIString)) {
                return false;
            }
            return key.equalsIgnoreCase(((CIString) obj).key);
        }
String hash map that does not care about key case.
stroom-util/src/main/java/stroom/util/CIStringHashMap.java