通用mapper实现复杂单表查询

 public PageResult<Brand> queryBrandByPage(Integer page, Integer rows, String sortBy, Boolean desc, String key) {
        //分页
        PageHelper.startPage(page,rows);
        //过滤
        Example example = new Example(Brand.class);
        if (StringUtils.isNotBlank(key)){
            example.createCriteria().orLike("name","%"+key+"%")
                    .orEqualTo("letter",key.toUpperCase());
        }
        //排序
        if (StringUtils.isNotBlank(sortBy)){
            String orderByclause = sortBy+(desc?" DESC":" ASC");
            example.setOrderByClause(orderByclause);
        }
        //查询
        List<Brand> list = brandMapper.selectByExample(example);
        if (CollectionUtils.isEmpty(list)){
            throw new ShopException(ExceptionEnum.BRAND_NOT_FIND);
        }
        //解析分页结果
        PageInfo<Brand> info = new PageInfo<>(list);

        return new PageResult<>(info.getTotal(),list);
    }

 

public PageResult<Brand> queryBrandByPage(Integer page, Integer rows, String sortBy, Boolean desc, String key) {
    //分页
PageHelper.startPage(page,rows);
//过滤
Example example = new Example(Brand.class);
    if (StringUtils.isNotBlank(key)){
        example.createCriteria().orLike("name","%"+key+"%")
                .orEqualTo("letter",key.toUpperCase());
}
    //排序
if (StringUtils.isNotBlank(sortBy)){
        String orderByclause = sortBy+(desc?" DESC":" ASC");
example.setOrderByClause(orderByclause);
}
    //查询
List<Brand> list = brandMapper.selectByExample(example);
    if (CollectionUtils.isEmpty(list)){
        throw new ShopException(ExceptionEnum.BRAND_NOT_FIND);
}
    //解析分页结果
PageInfo<Brand> info = new PageInfo<>(list);

    return new PageResult<>(info.getTotal(),list);
}