code: Date readDate(Node node, String propertyName) throws OrganizationServiceException
     {
        try
        {
           return node.getProperty(propertyName).getDate().getTime();
        }
        catch (PathNotFoundException e)
        {
           return null;
        }
        catch (ValueFormatException e)
        {
           throw new OrganizationServiceException("Property " + propertyName + " contains wrong value format", e);
        }
        catch (RepositoryException e)
        {
           throw new OrganizationServiceException("Can not read property " + propertyName, e);
        }
     }
docs: Returns property value represented in {@link Date}.
  
  @param node
  the parent node
  @param propertyName
  the property name to read from
  @return the date value if property exists or null otherwise
  @throws OrganizationServiceException
  if unexpected exception is occurred during reading