<> web阶段学习体验感【黑马java培训】

 @Override
    public List<Route> findByPage(int cid, int start, int pageSize,String rname) {
//
//        String sql = "select * from tab_route where cid = ? limit ? , ?";
//
//        return jtl.query(sql,new BeanPropertyRowMapper<Route>(Route.class),cid,start,pageSize);

        String sql = "select * from tab_route where 1=1";
        StringBuilder sb = new StringBuilder(sql);
        ArrayList arr = new ArrayList<>();

        if (cid != 0) {
            sb.append(" and cid = ? ");
            arr.add(cid);//添加？对应的值
        }


        if (rname != null && rname.length() > 0&& !"null".equals(rname)) {
            sb.append(" and rname like ?");
            arr.add("%" + rname + "%");
        }
        arr.add(start);
        arr.add(pageSize);

        sb.append(" limit ? , ? ");
        sql = sb.toString();


        return jtl.query(sql, new BeanPropertyRowMapper<Route>(Route.class), arr.toArray());

    }