public void attachedToSource(ICreateConnectionContext contex) {

      PictogramElement pe = context.getSourcePictogramElement();

      ILocation loc = context.getSourceLocation();

      // I retrieve the diagram's editing domain
      TransactionalEditingDomain editingDomain = getDiagramBehavior().getEditingDomain();

      // I create my command which will create the anchor dynamically in the source pictogram element
      AddCommandAnchorMessage cmd = new AddCommandAnchorMessage(editingDomain, pe, loc);

      // I execute this command
      editingDomain.getCommandStack().execute(cmd);

      // I change the source anchor in the context
      ((CreateConnectionContext)context).setSourceAnchor(cmd.getAnchorCreated);
}