void fireRolesChanged(RoleSet changedRoleSet) {
RoleEvent event = new RoleEvent(this, changedRoleSet);
for (int i=0; i<myListeners.size(); i++) {
Listener next = (Listener) myListeners.get(i);
next.rolesChanged(event);
}
}
private void createRoleSet() {
GanttLanguage language = GanttLanguage.getInstance();