Review

class MetaFormatSupport {
    /**
     * Invert the specified Map.
     * 
     * @param map the Map to invert.
     * @return a new Map instance.
     * @throws NullPointerException if <code>map</code> is <code>null</code>.
     */
    protected Map invert(Map map) {
        Map result = new HashMap(map.size());
        for (Iterator iter = map.entrySet().iterator(); iter.hasNext();) {
            Map.Entry entry = (Map.Entry) iter.next();
            result.put(entry.getValue(), entry.getKey());
        }
        return result;
    }

}