SpringBoot案例-员工管理-分页查询-实现

news2024/10/5 22:41:25

前言：

阅读本文前，请先浏览分页功能分析文章，文章传送门SpringBoot案例-员工管理-分页查询-分析_熵240的博客-CSDN博客

根据三层架构中各个层次的作用进行编码

功能接口的实现

控制层（Controller类）

具体关键代码如下：

   @GetMapping("/emps")
    // 接收前端参数默认根据名称进行自动注入
    public Result page(@RequestParam(defaultValue = "1") Integer page, @RequestParam(defaultValue = "10") Integer pageSize) {
        // 设置未接受到参数值时，设置其默认值
        // if (page == null) page = 1;
        // if (pageSize == null) pageSize = 10;
        log.info("分页查询,参数page：{}、pageSize：{}", page, pageSize);
        // 调用Service中的方法进行分页查询
        // 查询的结果封装到PageBean中
        PageBean pageBean = empService.Page(page, pageSize);
        return Result.success(pageBean);
    }

业务层（Service类）

具体关键代码如下：

业务类

PageBean Page(Integer page, Integer pageSize);

业务实现类

    public PageBean Page(Integer page, Integer pageSize) {
        // 获取总记录数
        long count = empMapper.CountAll();
        Integer start = page * pageSize - pageSize;
        // 获取分页查询结果列表
        List<Emp> list = empMapper.GetData(start, pageSize);
        // 封装PageBean对象
        PageBean pageBean = new PageBean(count, list);
        return pageBean;

    }

持久层

具体关键代码如下：

  /**
     * 获取数据总数
     *
     * @return
     */
    @Select("select count(*) from emp")
    public long CountAll();

    /**
     * 获取每页数据信息
     *
     * @return
     */
    @Select("select * from emp limit #{start},#{pageSize}")
    public List<Emp> GetData(Integer start, Integer pageSize);

接口测试

在启动SpringBoot工程之后，在postman中进行接口测试，具体的请求路径及参数如下：

运行结果如下：

{
    "code": 1,
    "msg": "success",
    "data": {
        "total": 17,
        "rows": [
            {
                "id": 1,
                "username": "jinyong",
                "password": "123456",
                "name": "金庸",
                "gender": 1,
                "image": "1.jpg",
                "job": 4,
                "entrydate": "2000-01-01",
                "deptId": 2,
                "creteTime": null,
                "updateTime": "2023-08-07T15:44:50"
            },
            {
                "id": 2,
                "username": "zhangwuji",
                "password": "123456",
                "name": "张无忌",
                "gender": 1,
                "image": "2.jpg",
                "job": 2,
                "entrydate": "2015-01-01",
                "deptId": 2,
                "creteTime": null,
                "updateTime": "2023-08-07T15:44:50"
            },
            {
                "id": 3,
                "username": "yangxiao",
                "password": "123456",
                "name": "杨逍",
                "gender": 1,
                "image": "3.jpg",
                "job": 2,
                "entrydate": "2008-05-01",
                "deptId": 2,
                "creteTime": null,
                "updateTime": "2023-08-07T15:44:50"
            },
            {
                "id": 4,
                "username": "weiyixiao",
                "password": "123456",
                "name": "韦一笑",
                "gender": 1,
                "image": "4.jpg",
                "job": 2,
                "entrydate": "2007-01-01",
                "deptId": 2,
                "creteTime": null,
                "updateTime": "2023-08-07T15:44:50"
            },
            {
                "id": 5,
                "username": "changyuchun",
                "password": "123456",
                "name": "常遇春",
                "gender": 1,
                "image": "5.jpg",
                "job": 2,
                "entrydate": "2012-12-05",
                "deptId": 2,
                "creteTime": null,
                "updateTime": "2023-08-07T15:44:50"
            }
        ]
    }
}