@Override
    @NonNull
    public Set<Entry<String, V>> entrySet() {
        return new EntrySet<>(this.map.entrySet(), this);
    }
Convert the given key <code>Object</code> to a {@link CaseInsensitiveKey}.
<p/>
Pre-condition: <code>key</code> instanceof <code>String</code>

@param key the key to be converted
@return the <code>CaseInsensitiveKey</code> corresponding to the given key
netbare-injector/src/main/java/com/github/megatronking/netbare/utils/CaseInsensitiveLinkedMap.java