*
   * @param index the index of the stripe to return; must be in {@code [0...size())}
   * @return the stripe at the specified index
   */
  public abstract L getAt(int index);

  /**
   * Returns the index to which the given key is mapped, so that getAt(indexFor(key)) == get(key).
   */
  abstract int indexFor(Object key);

  /** Returns the total number of stripes in this instance. */
  public abstract int size();

        return pd;
    }

    @Override
    public PropertyDesc getPropertyDesc(final int index) {
        assertArgumentArrayIndex("index", index, getPropertyDescSize());

        return propertyDescCache.getAt(index);
    }

    @Override
    public int getPropertyDescSize() {
        return propertyDescCache.size();
    }

    @Override
    public Iterable<PropertyDesc> getPropertyDescs() {