Redis를 사용하여 좋아요를 누르고 취소하는 방법

/** * * @param userId 点赞的人 * @param type 点赞与取消点赞的表示 * @param textId 文章ID * @param entityUserId -- 被点赞的人，文章作者 */ private void like(long userId,int type,int textId,long entityUserId){ redisTemplate.execute(new SessionCallback() { @Override public Object execute(RedisOperations operations) throws DataAccessException { String entityLikeKey = RedisKeyUtil.getEntityLikeKey(type, textId); String userLikeKey = RedisKeyUtil.getUserLikeKey(entityUserId); boolean isMember = redisTemplate.opsForSet().isMember(entityLikeKey, userId); //多个更新操作，需要事务 operations.multi(); if (isMember) { //取消赞 redisTemplate.opsForSet().remove(entityLikeKey, userId); redisTemplate.opsForValue().decrement(userLikeKey); } else { //点赞 redisTemplate.opsForSet().add(entityLikeKey, userId); redisTemplate.opsForValue().increment(userLikeKey); } return operations.exec(); } }); } /** *查询某实体（帖子，评论等）点赞数量 * @param type 1点赞，2评论。0表示取消点赞 * @param textId * @return */ private long findEntityLikeCount(int type, int textId){ String entityLikeKey = RedisKeyUtil.getEntityLikeKey(type, textId); return redisTemplate.opsForSet().size(entityLikeKey); } /** * 查询某人对某文章的点赞状态 * @param textId 帖子ID * @param userId * @return */ private int findEntityLikeStatus(int textId,long userId){ String entityLikeKey = RedisKeyUtil.getEntityLikeKey(1, textId); //此处返回int，是为了进行扩展。比如扩展踩，为止2.等等情况 return redisTemplate.opsForSet().isMember(entityLikeKey,userId)?1:0; } /** * 查询某个用户获得赞，用于在个人主页查看收获了多少赞 * @param userId * @return */ private int findUserLikeCount(long userId){ String userLikeKey = RedisKeyUtil.getUserLikeKey(userId); Integer count = (Integer) redisTemplate.opsForValue().get(userLikeKey); // count.intValue()数据的整数形式; return count==null?0:count.intValue(); }

public class RedisKeyUtil { private static final String SPLIT = ":"; private static final String PREFIX_ENTITY_LIKE = "like:entity"; private static final String PREFIX_USER_LIKE = "like:user"; private static final String PREFIX_USER_COMMENTS="comments:user"; /** *某个实体收到的赞，如帖子， * like:entity:entityType:entityId -> set(userId) 对应set，存入userId * @param entityType * @param entityId * @return */ public static String getEntityLikeKey(int entityType, int entityId) { return PREFIX_ENTITY_LIKE + entityType + SPLIT + entityId; } *某个用户收到的总赞数 * like:user:userId ->long * @param userId public static String getUserLikeKey(long userId) { return PREFIX_USER_LIKE + SPLIT + userId; * 汇总某个帖子的评论数量 public static String getUserCommentsKey(int articleId) { return PREFIX_USER_COMMENTS + SPLIT + articleId;