实现课程列表接口

1、带条件查询带分页的课程列表

（1）创建条件查询的vo 在service_edu模块中com/atguigu/eduservice/entity/vo编写CourseQueryVo类。

java 复制代码

@Data
public class CourseQueryVo {

    @ApiModelProperty(value = "课程名称")
    private String title;

    @ApiModelProperty(value = "讲师id")
    private String teacherId;

    @ApiModelProperty(value = "一级类别id")
    private String subjectParentId;

    @ApiModelProperty(value = "二级类别id")
    private String subjectId;

    @ApiModelProperty(value = "销量排序")
    private String buyCountSort;

    @ApiModelProperty(value = "最新时间排序")
    private String gmtCreateSort;

    @ApiModelProperty(value = "价格排序")
    private String priceSort;
}

（2）在com/atguigu/eduservice/api编写CourseApiController

java 复制代码

@Api(description="前台课程展现")
@RestController
@RequestMapping("/eduservice/courseapi")
@CrossOrigin
public class CourseApiController {
    @Autowired
    private EduCourseService courseService;

    @ApiOperation(value = "带条件分页查询课程列表")
    @PostMapping("getFrontCourseList/{current}/{limit}")
    public R getTeacherPageVo(@PathVariable Long current,
                              @PathVariable Long limit,
                              @RequestBody CourseQueryVo courseQueryVo){
        Page<EduCourse> page = new Page<>(current,limit);
        Map<String,Object> map = courseService.getCoursePageList(page,courseQueryVo);
        return R.ok().data(map);
    }  
}

（3）在EduCourseService中添加带条件分页查询课程列表接口

java 复制代码

Map<String, Object> getCoursePageList(Page<EduCourse> page, CourseQueryVo courseQueryVo);

（4）在EduCourseServiceImpl中实现接口的方法

java 复制代码

//带条件分页查询课程列表(前台)
@Override
public Map<String, Object> getCoursePageList(Page<EduCourse> pageParam, CourseQueryVo courseQueryVo) {
    //1取出查询条件
    String subjectParentId = courseQueryVo.getSubjectParentId();//一级分类
    String subjectId = courseQueryVo.getSubjectId();//二级分类
    String buyCountSort = courseQueryVo.getBuyCountSort();//关注度
    String priceSort = courseQueryVo.getPriceSort();//价格
    String gmtCreateSort = courseQueryVo.getGmtCreateSort();//时间

    //2条件判断
    QueryWrapper<EduCourse> wrapper = new QueryWrapper<>();
    if(!StringUtils.isEmpty(subjectParentId)){
        wrapper.eq("subject_parent_id",subjectParentId);
    }
    if(!StringUtils.isEmpty(subjectId)){
        wrapper.eq("subject_id",subjectId);
    }
    if(!StringUtils.isEmpty(buyCountSort)){
        wrapper.orderByDesc("buy_count");
    }
    if(!StringUtils.isEmpty(priceSort)){
        wrapper.orderByDesc("price");
    }
    if(!StringUtils.isEmpty(gmtCreateSort)){
        wrapper.orderByDesc("gmt_create");
    }
    //3查询数据
    baseMapper.selectPage(pageParam,wrapper);
    //4封装数据
    List<EduCourse> records = pageParam.getRecords();
    long current = pageParam.getCurrent();
    long pages = pageParam.getPages();
    long size = pageParam.getSize();
    long total = pageParam.getTotal();
    boolean hasNext = pageParam.hasNext();
    boolean hasPrevious = pageParam.hasPrevious();

    Map<String, Object> map = new HashMap<String, Object>();
    map.put("items", records);
    map.put("current", current);
    map.put("pages", pages);
    map.put("size", size);
    map.put("total", total);
    map.put("hasNext", hasNext);
    map.put("hasPrevious", hasPrevious);

    return map;
}