docs: public V retrieve(K key) {
  		V retval = null;
  		if (isCachingEnabled()) {
  			CachedObject<V> co = getCachedObject(key);
  			if (co == null || (isCachedObjectExpired(co))) {
  				//take pressure off of cleanup
  				misses++;
  			} else if (co.getObject() == null) {
  				unavailable++;
  			} else {
  				hits++;
  				retval = co.getObject();
  			}
  		}
  		return retval;
  	}