@Override
 public void write(DOMOutput out) throws IOException {
   super.write(out);
   out.openElement("locator");
   out.writeObject(locator);
   out.closeElement();
 }
 @Override
 public void read(DOMInput in) throws IOException {
   super.read(in);
   in.openElement("locator");
   this.locator = (Locator) in.readObject(0);
   in.closeElement();
 }
 /** Reads the arrow tip from a StorableInput. */
 public void read(StorableInput dr) throws IOException {
   super.read(dr);
   fLocator = (Locator) dr.readStorable();
 }
 /** Stores the arrow tip to a StorableOutput. */
 public void write(StorableOutput dw) {
   super.write(dw);
   dw.writeStorable(fLocator);
 }