业务需求：A、B两个用户的关注/取消关注接口
1、建表
由数据库设计文档和数据库存放关系可知，
数据 用户的userId 既可以在数据库的user_id位置，也可以在数据库的follower_id位置上。
2、该接口的实现思路如下
2.1、关注/取消关注 用户的设计思路
参数：用户A、用户B、关注/取消关注flag
A和B的关系，假设A在数据库的A位置
00 A关注B
01 B关注A
02 A、B相互关注
备注：A在数据库的B位置时，如上关系为01、00、02
2.2、实现思路如下：
0.去数据库查询A、B这两个用户有没有关系(00/01/02)
1.点击关注 --说明A和B的关系：1>没有关系；2>B关注A
1-1.判断A和B的关系
1-2.如果没有关系，则添加一条数据
1-3.如果有关系，则将关系改为相互关注(这个要结合实际，如果A已经关注了B，则A不能在关注B了，即进来
的肯定是B点击了关注A)
2.3、点击取消关注 --说明A和B的关系：
1>A关注B；2>A、B相互关注
2.4、判断A和B的关系
2.4.1.如果是关注(结合实际，只有相互关注和关注两种关系)，则取消关注，即删除这条数据
2.4.2.如果是相互关注，则需要判断A和B的位置
2.4.3 如果A在数据库的A位置，则修改A和B的关系为被关注--即关系为01
2.4.4 如果A在数据库的B位置，则修改A和B的关系为被关注--即关系为00
3、Java代码实现
/** * 添加用户关注(关注、取消关注) * @param json * @return */ @PostMapping("/addUserRelationShip") public Map<String,Object> addUserRelationShip(@RequestBody String json) { Map<String, Object> resultMap = new HashMap<>(); UserRelationShip relationShip = JSON.parseObject(json, UserRelationShip.class); relationShip.setRelationId(UUID.randomUUID().toString().replace("-", "")); System.out.println(relationShip); JSONObject jsonObject = JSONObject.parseObject(json); Integer status = jsonObject.getInteger("status"); String userId = jsonObject.getString("userId"); String followerId = jsonObject.getString("followerId"); //获取A和B的关系 List<UserRelationShip> userRelationShips = relationShipService.checkRelation(userId,followerId); if (userRelationShips.size() > 0 ) { //已经有关系了 System.out.println("有关系了"); UserRelationShip userRelationShip = userRelationShips.get(0); System.out.println(userRelationShip.getRelation()); String relation = userRelationShip.getRelation(); String relationUserId = userRelationShip.getUserId(); String relationFollowerId = userRelationShip.getFollowerId(); String position = ""; if (userId.equals(relationUserId)) { position = "left"; } else if (userId.equals(relationFollowerId)) { position = "right"; } if (status == 1) { //执行关注操作 if (position.equals("left")) { if (relation.equals("00") || relation.equals("02")) { //自己在左边：00:主动关注过对方，02：两人互关着呢，不能再执行关注操作了 resultMap.put("message", "关注失败，不能重复关注"); resultMap.put("state", JsonResult.failing); } else {//对方在关注你，但是你没有关注对方，所有执行操作，更改状态为02，变成互关的状态 int updateCount = relationShipService.updateRelationStatus(userId,followerId,"02"); if (updateCount > 0) { resultMap.put("message", "关注成功"); resultMap.put("state", JsonResult.SUCCESS); } else { resultMap.put("message", "关注失败"); resultMap.put("state", JsonResult.failing); } } } else { //说明自己在右边，关注是自己被对方主动关注过， if (relation.equals("01") || relation.equals("02")) { //自己在右边：01：自己关注别人了，02：两人互关呢，不能再执行关注操作了 resultMap.put("message", "关注失败，不能重复关注"); resultMap.put("state", JsonResult.failing); } else { //00:对方在关注你，但是你没有关注对方，所有执行操作，更改状态为02，变成互关的状态 int updateCount = relationShipService.updateRelationStatus(userId,followerId,"02"); if (updateCount > 0) { resultMap.put("message", "关注成功"); resultMap.put("state", JsonResult.SUCCESS); } else { resultMap.put("message", "关注失败"); resultMap.put("state", JsonResult.failing); } } } } else {//执行取关操作 if (position.equals("left")) { if (relation.equals("00")) { //此时只有自己关注了对方，但是对方，却没有关注自己，所以执行取消操作的话，直接删除就行了 int deleteCount = relationShipService.deleteUserRelationShip(userId,followerId); if (deleteCount > 0) { resultMap.put("message", "取消关注成功"); resultMap.put("state", JsonResult.SUCCESS); } else { resultMap.put("message", "取消关注失败"); resultMap.put("state", JsonResult.failing); } } else if (relation.equals("02")) { //两人互关呢，自己执行取关操作，要更改状态为01 int updateCount = relationShipService.updateRelationStatus(userId,followerId,"01"); if (updateCount > 0) { resultMap.put("message", "取消关注成功"); resultMap.put("state", JsonResult.SUCCESS); } else { resultMap.put("message", "取消关注失败"); resultMap.put("state", JsonResult.failing); } } else { //01时候，对方在关注者自己，就没关注别人，取关个毛线啊 resultMap.put("message", "取消关注失败"); resultMap.put("state", JsonResult.failing); } } else { //说明自己在右边，关注是自己被对方主动关注过， if (relation.equals("01")) { //自己关注了对方，但是对方却没有关注自己，直接删除就行了 int deleteCount = relationShipService.deleteUserRelationShip(userId,followerId); if (deleteCount > 0) { resultMap.put("message", "取消关注成功"); resultMap.put("state", JsonResult.SUCCESS); } else { resultMap.put("message", "取消关注失败"); resultMap.put("state", JsonResult.failing); } } else if (relation.equals("02")) { int updateCount = relationShipService.updateRelationStatus(userId,followerId,"00"); if (updateCount > 0) { resultMap.put("message", "取消关注成功"); resultMap.put("state", JsonResult.SUCCESS); } else { resultMap.put("message", "取消关注失败"); resultMap.put("state", JsonResult.failing); } } else { //你都没关注别人，取关个毛线啊 resultMap.put("message", "取消关注失败"); resultMap.put("state", JsonResult.failing); } } } } else { //没有关系 System.out.println("没有关系"); relationShip.setRelation("00"); //既然没有关系，就新增一条，记录状态标记为00 int addCount = relationShipService.addUserRelationShip(relationShip); if (addCount > 0) { System.out.println("新增关系成功"); resultMap.put("message", "新增关注成功"); resultMap.put("state", JsonResult.SUCCESS); } else { resultMap.put("message", "新增关注失败"); resultMap.put("state", JsonResult.failing); } } return resultMap; }
备注：上述的sql语句：addUserRelationShip / deleteUserRelationShip / updateRelationStatus
<!-- 检查好友关系 --> <select id="checkRelation" resultMap="BasePlusResultMap"> select * from follower where (user_id = #{userId} and follower_id = #{followerId}) or (user_id = #{followerId} and follower_id = #{userId}) </select> <!-- 关注某人 --> <insert id="addUserRelationShip" > insert into follower(relation_id,user_id,follower_id,status,relation) values (#{relationId},#{userId},#{followerId},#{status},#{relation}) </insert> <!-- 取消关注某人 --> <delete id="deleteUserRelationShip"> delete from follower where user_id=#{userId} and follower_id = #{followerId} </delete> <!-- 更新还有关系状态 --> <update id="updateRelationStatus"> update follower set relation = #{relation} where (user_id = #{userId} and follower_id = #{followerId}) or (user_id = #{followerId} and follower_id = #{userId}) </update>
封装检查好友关系的逻辑代码，可以贴过去直接用的
public static int checkRelationStatus(String userId,String targetId,List<Fans> userRelationShips) { int relationStatus = 0; for (int index = 0;index < userRelationShips.size();index++) { Fans userRelationShip = userRelationShips.get(index); String relationShipUserId = userRelationShip.getUserId(); String relationShipFollowerId = userRelationShip.getFollowerId(); String relation = userRelationShip.getRelation(); if (relationShipUserId.equals(userId) && relationShipFollowerId.equals(targetId) || (relationShipUserId.equals(targetId) && relationShipFollowerId.equals(userId))) { String position = ""; if (userId.equals(relationShipUserId)) { position = "left"; } else if (userId.equals(relationShipFollowerId)) { position = "right"; } if (position.equals("left")) { if (relation.equals("00") || relation.equals("02")) { //自己在左边：00:主动关注过对方，02：两人互关着呢，不能再执行关注操作了 relationStatus = 1; } } else { //说明自己在右边，关注是自己被对方主动关注过， if (relation.equals("01") || relation.equals("02")) { //自己在右边：01：自己关注别人了，02：两人互关呢，不能再执行关注操作了 relationStatus = 1; } } break; } } return relationStatus; }
4、获取我的关注列表
/* *//** * 获取我的关注列表 * @param userId * @param page * @param pageSize * @return */ @GetMapping("/selectUserAttention") public Map<String,Object> selectUserAttention(String userId,int page,int pageSize){ Map<String,Object> resultMap = new HashMap<>(); List<RelationShipUser> relationUsers = new ArrayList<>(); Map<String,Object> paramMap = new HashMap<>(); paramMap.put("userId",userId); paramMap.put("followerId",userId); int pageCount = (page)* pageSize; paramMap.put("page", pageCount); paramMap.put("size",pageSize); List<Fans> userRelationShips = fansUserService.selectUserAttention(paramMap); if(userRelationShips.size() > 0) { List<String> userIds = new ArrayList<>(); for (int index = 0;index < userRelationShips.size();index++) { Fans userRelationShip = userRelationShips.get(index); String relationShipUserId = userRelationShip.getUserId(); String relationShipFollowerId = userRelationShip.getFollowerId(); if (relationShipFollowerId.equals(userId)) { userIds.add(relationShipUserId); } else { userIds.add(relationShipFollowerId); } } System.out.println(userIds); //获取用户 List<UserClone> users = relationShipService.queryUserWithIds(userIds); if (users.size() > 0) { for (int index = 0;index < users.size(); index++) { RelationShipUser relationShipUser = new RelationShipUser(); relationShipUser.setUser(users.get(index)); relationUsers.add(relationShipUser); } } for (int idx = 0;idx < relationUsers.size();idx++) { RelationShipUser relationShipUser = relationUsers.get(idx); String targetId = relationShipUser.getUser().getUserId(); int relationStatus = checkRelationStatus(userId,targetId,userRelationShips); relationShipUser.setStatus(relationStatus); relationUsers.set(idx,relationShipUser); } resultMap.put("data",relationUsers); resultMap.put("message", "查询关注人成功"); resultMap.put("state", JsonResult.SUCCESS); }else if(userRelationShips.size() == 0){ resultMap.put("data",relationUsers); resultMap.put("message", "你还没关注任何人"); resultMap.put("state", JsonResult.SUCCESS); }else { resultMap.put("message", "查询关注人失败"); resultMap.put("state", JsonResult.failing); } return resultMap; }
以上代码所用的Sql语句：selectUserAttention
<!--我的关注--> <select id="selectUserAttention" parameterType="Map" resultMap="BasePlusResultMap"> select * from follower where (follower.user_id = #{userId} and follower.relation in (‘00‘,‘02‘)) or (follower.follower_id = #{followerId} and follower.relation in (‘01‘,‘02‘)) LIMIT #{page}, #{size} </select>
5、获取我的粉丝
/** * 获取我的粉丝列表 * @param userId * @param page * @param pageSize * @return */ @GetMapping("/selectUserVermicelli") public Map<String,Object> selectUserVermicelli(String userId,int page,int pageSize){ Map<String,Object> resultMap = new HashMap<>(); List<RelationShipUser> relationUsers = new ArrayList<>(); Map<String,Object> paramMap = new HashMap<>(); paramMap.put("userId",userId); paramMap.put("followerId",userId); int pageCount = (page)* pageSize; paramMap.put("page", pageCount); paramMap.put("size",pageSize); List<Fans> userRelationShips = fansUserService.selectUserVermicelli(paramMap); if(userRelationShips.size() > 0){ List<String> userIds = new ArrayList<>(); for (int index = 0;index < userRelationShips.size();index++) { Fans userRelationShip = userRelationShips.get(index); String relationShipUserId = userRelationShip.getUserId(); String relationShipFollowerId = userRelationShip.getFollowerId(); if (relationShipFollowerId.equals(userId)) { userIds.add(relationShipUserId); } else { userIds.add(relationShipFollowerId); } } System.out.println(userIds); //获取用户 List<UserClone> users = relationShipService.queryUserWithIds(userIds); if (users.size() > 0) { for (int index = 0;index < users.size(); index++) { RelationShipUser relationShipUser = new RelationShipUser(); relationShipUser.setUser(users.get(index)); relationUsers.add(relationShipUser); } } for (int idx = 0;idx < relationUsers.size();idx++) { RelationShipUser relationShipUser = relationUsers.get(idx); String targetId = relationShipUser.getUser().getUserId(); int relationStatus = checkRelationStatus(userId,targetId,userRelationShips); relationShipUser.setStatus(relationStatus); relationUsers.set(idx,relationShipUser); } resultMap.put("data",relationUsers); resultMap.put("message", "查询成功"); resultMap.put("state", JsonResult.SUCCESS); }else if(userRelationShips.size() == 0){ resultMap.put("data",relationUsers); resultMap.put("message", ""); resultMap.put("state", JsonResult.SUCCESS); }else { resultMap.put("message", "查询失败"); resultMap.put("state", JsonResult.failing); } return resultMap; }
以上代码所用到的Sql：selectUserVermicelli
<!-- <!–我的粉丝--> <select id="selectUserVermicelli" resultMap="BasePlusResultMap" parameterType="Map"> select u2.nickname, u2.phone,u2.avatar,follower.follower_id ,follower.relation_id,u2.user_id,follower.relation,u2.description,follower.user_id from follower inner join dnx_app_user u1 on follower.follower_id = u1.user_id inner join dnx_app_user u2 on follower.user_id = u2.user_id where (follower.user_id = #{userId} and follower.relation in (‘01‘,‘02‘)) or (follower.follower_id = #{followerId} and follower.relation in (‘00‘,‘02‘)) LIMIT #{page}, #{size} </select>