1、全局的异常处理器
在对数据库的增删改查中,可能需要对一些异常需要进行抛出处理,比如说在数据库中插入了重复的数据等。因此可以在项目中自定义一个全局的异常处理器来处理一些异常。
![](https://www.icode9.com/i/l/?n=22&i=blog/2317869/202207/2317869-20220704124305740-2033864537.png)
2、分类实体类
![](https://www.icode9.com/i/l/?n=22&i=blog/2317869/202207/2317869-20220704124316254-1464498263.png)
3、创建Mapper、Service类
由于在分类功能中存在同时查两张表的情况,需要重写remove函数。
![](https://www.icode9.com/i/l/?n=22&i=blog/2317869/202207/2317869-20220704124330048-1602595188.png)
![](https://www.icode9.com/i/l/?n=22&i=blog/2317869/202207/2317869-20220704124336802-1119570559.png)
![](https://www.icode9.com/i/l/?n=22&i=blog/2317869/202207/2317869-20220704124341071-1465985678.png)
4、新增分类功能
![](https://www.icode9.com/i/l/?n=22&i=blog/2317869/202207/2317869-20220704124349057-1080124694.png)
5、分页查询功能
![](https://www.icode9.com/i/l/?n=22&i=blog/2317869/202207/2317869-20220704124357214-204187403.png)
6、通过id来删除分类
![](https://www.icode9.com/i/l/?n=22&i=blog/2317869/202207/2317869-20220704124408741-1328423374.png)
7、修改分类功能
![](https://www.icode9.com/i/l/?n=22&i=blog/2317869/202207/2317869-20220704124418964-1256807741.png)
8、按照条件查询
![](https://www.icode9.com/i/l/?n=22&i=blog/2317869/202207/2317869-20220704124429342-720650269.png)
标签:功能,数据库,分类,处理器,外卖,之瑞吉,全局,异常
来源: https://www.cnblogs.com/jiujiu123456/p/16442586.html