code: public static <T, K> Collection<T> findMapValuesByKey(Collection<K> aKeys,
  	Map<K, T> aMap)
  	{
  		if (aKeys == null || aMap == null)
  			return null;
  
  		Object key = null;
  		ArrayList<T> results = new ArrayList<T>(aMap.size());
  		for (Iterator<K> i = aKeys.iterator(); i.hasNext();)
  		{
  			key = i.next();
  			results.add(aMap.get(key));
  		}
  
  		results.trimToSize();
  
  		return results;
  	}
docs: Find values in map that match a given key
  
  @param <K>
  the key type
  @param <T>
  the map value type
  @param aKeys
  the keys
  @param aMap
  the map containing the data
  @return Collection of values