code: @SuppressWarnings({ "unchecked" })
      public static <V> V associate(Associator associator, Serializable id,
              V value) {
          associator.setAssociated(
              new TypedIdKey<V>((Class<V>) value.getClass(), id), value);
          return value;
      }
docs: Associates the given value's type and the id with the given value
  using the given associator.
  
  @param <V> the value type
  @param associator the associator
  @param id the id
  @param value the value
  @return the value for easy chaining