本章概要
- 准备工作
- 功能实现
- 前后联调
4.1 准备工作
- 数据库脚本
CREATE TABLE schedule (id INT NOT NULL AUTO_INCREMENT,title VARCHAR(255) NOT NULL,completed BOOLEAN NOT NULL,PRIMARY KEY (id)
);INSERT INTO schedule (title, completed)
VALUES('学习java', true),('学习Python', false),('学习C++', true),('学习JavaScript', false),('学习HTML5', true),('学习CSS3', false),('学习Vue.js', true),('学习React', false),('学习Angular', true),('学习Node.js', false),('学习Express', true),('学习Koa', false),('学习MongoDB', true),('学习MySQL', false),('学习Redis', true),('学习Git', false),('学习Docker', true),('学习Kubernetes', false),('学习AWS', true),('学习Azure', false);
- 准备 pojo
包：com.atguigu.pojo
/*** projectName: com.atguigu.pojo** description: 任务实体类*/
@Data
public class Schedule {private Integer id;private String title;private Boolean completed;
}
- 准备 R
包： com.atguigu.utils
*** projectName: com.atguigu.utils** description: 返回结果类*/
public class R {private int code = 200; //200成功状态码private boolean flag = true; //返回状态private Object data; //返回具体数据public static R ok(Object data){R r = new R();r.data = data;return r;}public static R fail(Object data){R r = new R();r.code = 500; //错误码r.flag = false; //错误状态r.data = data;return r;}public int getCode() {return code;}public void setCode(int code) {this.code = code;}public boolean isFlag() {return flag;}public void setFlag(boolean flag) {this.flag = flag;}public Object getData() {return data;}public void setData(Object data) {this.data = data;}
}
- 准备 PageBean
包： com.atguigu.utils
@Data
@NoArgsConstructor
@AllArgsConstructor
public class PageBean<T> {private int currentPage; // 当前页码private int pageSize; // 每页显示的数据量private long total; // 总数据条数private List<T> data; // 当前页的数据集合
}
4.2 功能实现
- 分页查询
- controller
/*@CrossOrigin 注释在带注释的控制器方法上启用跨源请求*/
@CrossOrigin
@RequestMapping("schedule")
@RestController
public class ScheduleController
{@Autowiredprivate ScheduleService scheduleService;@GetMapping("/{pageSize}/{currentPage}")public R showList(@PathVariable(name = "pageSize") int pageSize, @PathVariable(name = "currentPage") int currentPage){PageBean<Schedule> pageBean = scheduleService.findByPage(pageSize,currentPage);return R.ok(pageBean);}
}
- service
@Slf4j
@Service
public class ScheduleServiceImpl implements ScheduleService {@Autowiredprivate ScheduleMapper scheduleMapper;/*** 分页数据查询,返回分页pageBean** @param pageSize* @param currentPage* @return*/@Overridepublic PageBean<Schedule> findByPage(int pageSize, int currentPage) {//1.设置分页参数PageHelper.startPage(currentPage,pageSize);//2.数据库查询List<Schedule> list = scheduleMapper.queryPage();//3.结果获取PageInfo<Schedule> pageInfo = new PageInfo<>(list);//4.pageBean封装PageBean<Schedule> pageBean = new PageBean<>(pageInfo.getPageNum(),pageInfo.getPageSize(),pageInfo.getTotal(),pageInfo.getList());log.info("分页查询结果:{}",pageBean);return pageBean;}}
- mapper
mapper 接口
public interface ScheduleMapper {List<Schedule> queryPage();
}
mapper.xml 文件
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""https://mybatis.org/dtd/mybatis-3-mapper.dtd">
<!-- namespace等于mapper接口类的全限定名,这样实现对应 -->
<mapper namespace="com.atguigu.mapper.ScheduleMapper"><select id="queryPage" resultType="schedule">select * from schedule</select>
</mapper>
- 计划添加
- controller
@PostMapping
public R saveSchedule(@RequestBody Schedule schedule){scheduleService.saveSchedule(schedule);return R.ok(null);
}
- service
/*** 保存学习计划** @param schedule*/
@Override
public void saveSchedule(Schedule schedule) {scheduleMapper.insert(schedule);
}
- mapper
mapper 接口
void insert(Schedule schedule);
mapper.xml 文件
<insert id="insert">insert into schedule (title, completed)values(#{title}, #{completed});
</insert>
- 计划删除
- controller
@DeleteMapping("/{id}")
public R removeSchedule(@PathVariable Integer id){scheduleService.removeById(id);return R.ok(null);
}
- service
/*** 移除学习计划** @param id*/
@Override
public void removeById(Integer id) {scheduleMapper.delete(id);
}
- mapper
mapper 接口
void delete(Integer id);
mapper.xml 文件
<delete id="delete">delete from schedule where id = #{id}
</delete>
- 计划修改
- controller
@PutMappingpublic R changeSchedule(@RequestBody Schedule schedule){scheduleService.updateSchedule(schedule);return R.ok(null);
}
- service
/*** 更新学习计划** @param schedule*/
@Override
public void updateSchedule(Schedule schedule) {scheduleMapper.update(schedule);
}
- mapper
mapper 接口
void update(Schedule schedule);
mapper.xml 文件
<update id="update">update schedule set title = #{title} , completed = #{completed}where id = #{id}
</update>
4.3 前后联调
- 后台项目根路径设计
- 启动测试即可
