protected void updatePositions(DocumentEvent event){
  for (  PositionUpdater u : fPositionUpdaters) {
    u.update(event);
  }
}

protected void updatePositions ( DocumentEvent event ) { for ( PositionUpdater u : fPositionUpdaters ) { u . update ( event ) ; } }
updates all positions of all categories to the change described by the document event . all registered document updaters are called in the sequence they have been arranged .
