redistemplate实现点赞相关功能

使用Redis的SET数据结构来存储每个实体的点赞用户ID列表，方便进行点赞数量的计数和用户点赞状态的检查。以下是一个小demo，只提供简单思路。

@Service
public class LikeService {


    @Autowired
    private RedisTemplate redisTemplate;

    //点赞
    public Long like(String userId,String entityId){
        String key = "like:" + entityId;
        return redisTemplate.opsForSet().add(key,userId) == 1L ? 1L : 0L;
    }

    //取消点赞
    public Long unLike(String userId,String entityId){
        String key = "like:" + entityId;
        return redisTemplate.opsForSet().remove(key,userId) == 1L ? 1L : 0L;
    }

    //查询点赞数量
    public Long isLiked(String userId,String entityId){
        String key = "like:" + entityId;
        return redisTemplate.opsForSet().remove(key,userId) == 1L ? 1L : 0L;
    }

    //查询用户点赞状态
    public Long countLikes(String entityId){
        String key = "like:" + entityId;
        return redisTemplate.opsForSet().size(key).longValue();
    }
}