jfinal异常时的事务回滚

Db.tx(new IAtom(){
@Override
public boolean run()throws SQLException{
JsonResult result;
try{
WebNavMenu.dao.deleteById(getPara("id"));
result = JsonResult.success("删除菜单成功");
renderJson(result);
}catch(Exception e){
result = JsonResult.fail("删除菜单失败");
renderJson(result);
return false;//事务回滚
}
return true;//成功执行
}
});