code: public Geometry pickGeometry( long position, long size ) throws Exception {
          byte[] geomBytes = new byte[(int) size];
          raf.seek(position);
          raf.read(geomBytes);
  
          ObjectInputStream in = new ObjectInputStream(new ByteArrayInputStream(geomBytes));
          return (Geometry) in.readObject();
      }
docs: Reads a single geomtry, using the info from the quadtree read in {@link #readIndex()}.
  
  @param position the position of the geom to read.
  @param size the size of the geom to read.
  @return the read geometry.
  @throws Exception