code: public T get(final UUID _uuid)
      {
          return getCache4UUID() == null ? null : getCache4UUID().get(_uuid);
      }
docs: Returns for given key id the cached object from the cache4Id cache. If
  the cache was not initialized yet, <code>null</code> is returned.
  
  @see #getCache4UUID()
  @param _uuid     UUID of the cached object
  @return cached object