}
  }
  private String select(Envelope envelop,int size) {
    SelectIterator it = new SelectIterator(envelop);
    List<Layer> layers = getLayers();
    //Log.log(Logger.Debug, "layer size " + layers.size());
    for (Layer layer : layers) {
      if (layer instanceof VectorLayer) {
        VectorLayer vl = (VectorLayer) layer;