1、Redis概述

• Redis是一款基于键值对的NoSQL数据库，它的值支持多种数据结构： 字符串(strings)、哈希(hashes)、列表(lists)、集合(sets)、有序集合(sorted sets)等。
• Redis将所有的数据都存放在内存中，所以它的读写性能十分惊人。 同时，Redis还可以将内存中的数据以快照或日志的形式保存到硬盘上，以保证数据的安全性。
• Redis典型的应用场景包括：缓存、排行榜、计数器、社交网络、消息队列等。
https://redis.io
https://github.com/microsoftarchive/redis

windows版本下载地址：https://github.com/microsoftarchive/redis/releases/tag/win-3.2.100
1、安装完成后配置环境变量
2、命令行输入redis-cli检验环境变量是否配置完成

2、Redis整合springboot

1、导入依赖pom.xml

  1.              <dependency>
  2.             <groupId>org.springframework.boot</groupId>
  3.             <artifactId>spring-boot-starter-data-redis</artifactId>
  4.         </dependency>

2、配置redis
application.properties

  1. #配置redis
  2. spring.redis.database=10
  3. spring.redis.host=localhost
  4. spring.redis.port=6379

3、配置类设置redis属性

  1. @Configuration
  2. public class RedisConfig {
  4.     @Bean
  5.     public RedisTemplate<String,Object> redisTemplate(RedisConnectionFactory factory){
  6.         RedisTemplate<String,Object> template=new RedisTemplate<>();
  7.         template.setConnectionFactory(factory);
  9.         //设置key的序列化方式
  10.         template.setKeySerializer(RedisSerializer.string());
  11.         //设置value的序列化方式
  12.         template.setValueSerializer(RedisSerializer.json());
  13.         //设置hashKey的序列化方式
  14.         template.setHashKeySerializer(RedisSerializer.string());
  15.         //设置hashValue的序列化方式
  16.         template.setHashValueSerializer(RedisSerializer.json());
  18.         template.afterPropertiesSet();
  19.         return template;
  20.     }
  21. }

4、测试各种属性

  1. @Test
  2.     public void testStrings() {
  3.         String redisKey = "test:count";
  5.         redisTemplate.opsForValue().set(redisKey, 1);
  7.         System.out.println(redisTemplate.opsForValue().get(redisKey));
  8.         System.out.println(redisTemplate.opsForValue().increment(redisKey));
  9.         System.out.println(redisTemplate.opsForValue().decrement(redisKey));
  10.     }
  12.     @Test
  13.     public void testHashes() {
  14.         String redisKey = "test:user";
  16.         redisTemplate.opsForHash().put(redisKey, "id", 1);
  17.         redisTemplate.opsForHash().put(redisKey, "username", "zhangsan");
  19.         System.out.println(redisTemplate.opsForHash().get(redisKey, "id"));
  20.         System.out.println(redisTemplate.opsForHash().get(redisKey, "username"));
  21.     }
  23.     @Test
  24.     public void testLists() {
  25.         String redisKey = "test:ids";
  27.         redisTemplate.opsForList().leftPush(redisKey, 101);
  28.         redisTemplate.opsForList().leftPush(redisKey, 102);
  29.         redisTemplate.opsForList().leftPush(redisKey, 103);
  31.         System.out.println(redisTemplate.opsForList().size(redisKey));
  32.         System.out.println(redisTemplate.opsForList().index(redisKey, 0));
  33.         System.out.println(redisTemplate.opsForList().range(redisKey, 0, 2));
  35.         System.out.println(redisTemplate.opsForList().leftPop(redisKey));
  36.         System.out.println(redisTemplate.opsForList().leftPop(redisKey));
  37.         System.out.println(redisTemplate.opsForList().leftPop(redisKey));
  38.     }
  40.     @Test
  41.     public void testSets() {
  42.         String redisKey = "test:teachers";
  44.         redisTemplate.opsForSet().add(redisKey, "刘备", "关羽", "张飞", "赵云", "诸葛亮");
  46.         System.out.println(redisTemplate.opsForSet().size(redisKey));
  47.         System.out.println(redisTemplate.opsForSet().pop(redisKey));
  48.         System.out.println(redisTemplate.opsForSet().members(redisKey));
  49.     }
  51.     @Test
  52.     public void testSortedSets() {
  53.         String redisKey = "test:students";
  55.         redisTemplate.opsForZSet().add(redisKey, "唐僧", 80);
  56.         redisTemplate.opsForZSet().add(redisKey, "悟空", 90);
  57.         redisTemplate.opsForZSet().add(redisKey, "八戒", 50);
  58.         redisTemplate.opsForZSet().add(redisKey, "沙僧", 70);
  59.         redisTemplate.opsForZSet().add(redisKey, "白龙马", 60);
  61.         System.out.println(redisTemplate.opsForZSet().zCard(redisKey));
  62.         System.out.println(redisTemplate.opsForZSet().score(redisKey, "八戒"));
  63.         System.out.println(redisTemplate.opsForZSet().reverseRank(redisKey, "八戒"));
  64.         System.out.println(redisTemplate.opsForZSet().reverseRange(redisKey, 0, 2));
  65.     }
  67.     @Test
  68.     public void testKeys() {
  69.         redisTemplate.delete("test:user");
  71.         System.out.println(redisTemplate.hasKey("test:user"));
  73.         redisTemplate.expire("test:students", 10, TimeUnit.SECONDS);
  74.     }
  76.     // 批量发送命令,节约网络开销.
  77.     @Test
  78.     public void testBoundOperations() {
  79.         String redisKey = "test:count";
  80.         BoundValueOperations operations = redisTemplate.boundValueOps(redisKey);
  81.         operations.increment();
  82.         operations.increment();
  83.         operations.increment();
  84.         operations.increment();
  85.         operations.increment();
  86.         System.out.println(operations.get());
  87.     }
  89.     // 编程式事务
  90.     @Test
  91.     public void testTransaction() {
  92.         Object result = redisTemplate.execute(new SessionCallback() {
  93.             @Override
  94.             public Object execute(RedisOperations redisOperations) throws DataAccessException {
  95.                 String redisKey = "text:tx";
  97.                 // 启用事务
  98.                 redisOperations.multi();
  99.                 redisOperations.opsForSet().add(redisKey, "zhangsan");
  100.                 redisOperations.opsForSet().add(redisKey, "lisi");
  101.                 redisOperations.opsForSet().add(redisKey, "wangwu");
  103.                 System.out.println(redisOperations.opsForSet().members(redisKey));
  105.                 // 提交事务
  106.                 return redisOperations.exec();
  107.             }
  108.         });
  109.         System.out.println(result);
  110.     }

3、点赞功能

1、生成redis的key的工具类RedisKeyUtil

  1. public class RedisKeyUtil {
  3.     private static final String SPLIT = ":";
  4.     private static final String PREFIX_ENTITY_LIKE = "like:entity";
  6.     // 某个实体的赞
  7.     // like:entity:entityType:entityId -> set(userId)
  8.     public static String getEntityLikeKey(int entityType, int entityId) {
  9.         return PREFIX_ENTITY_LIKE + SPLIT + entityType + SPLIT + entityId;
  10.     }
  11. }

2、查询点赞数量，点赞状态，以及某实体的点赞数量LikeService

  1. @Service
  2. public class LikeService {
  4.     @Autowired
  5.     private RedisTemplate redisTemplate;
  7.     /**
  8.      * 点赞
  9.      * @param userId
  10.      * @param entityType
  11.      * @param entityId
  12.      */
  13.     public void like(int userId, int entityType, int entityId) {
  14.         String entityLikeKey = RedisKeyUtil.getEntityLikeKey(entityType, entityId);
  15.         boolean isMember = redisTemplate.opsForSet().isMember(entityLikeKey, userId);
  16.         if (isMember) {
  17.             redisTemplate.opsForSet().remove(entityLikeKey, userId);
  18.         } else {
  19.             redisTemplate.opsForSet().add(entityLikeKey, userId);
  20.         }
  21.     }
  23.     /**
  24.      * 查询某实体点赞的数量
  25.      * @param entityType
  26.      * @param entityId
  27.      * @return
  28.      */
  29.     public long findEntityLikeCount(int entityType, int entityId) {
  30.         String entityLikeKey = RedisKeyUtil.getEntityLikeKey(entityType, entityId);
  31.         return redisTemplate.opsForSet().size(entityLikeKey);
  32.     }
  34.     /**
  35.      * 查询某人对某实体的点赞状态
  36.      * @param userId
  37.      * @param entityType
  38.      * @param entityId
  39.      * @return
  40.      */
  41.     public int findEntityLikeStatus(int userId, int entityType, int entityId) {
  42.         String entityLikeKey = RedisKeyUtil.getEntityLikeKey(entityType, entityId);
  43.         return redisTemplate.opsForSet().isMember(entityLikeKey, userId) ? 1 : 0;
  44.     }
  46. }

3、LikeController

  1. @Controller
  2. public class LikeController {
  4.     @Autowired
  5.     private LikeService likeService;
  7.     @Autowired
  8.     private HostHolder hostHolder;
  10.     /**
  11.      * 查询点赞数量接口
  12.      * @param entityType
  13.      * @param entityId
  14.      * @return
  15.      */
  16.     @PostMapping("/like")
  17.     @ResponseBody
  18.     public String like(int entityType, int entityId) {
  19.         User user = hostHolder.getUser();
  21.         // 点赞
  22.         likeService.like(user.getId(), entityType, entityId);
  24.         // 数量
  25.         long likeCount = likeService.findEntityLikeCount(entityType, entityId);
  26.         // 状态
  27.         int likeStatus = likeService.findEntityLikeStatus(user.getId(), entityType, entityId);
  28.         // 返回的结果
  29.         Map<String, Object> map = new HashMap<>();
  30.         map.put("likeCount", likeCount);
  31.         map.put("likeStatus", likeStatus);
  33.         return CommunityUtil.getJSONString(0, null, map);
  34.     }
  35. }

4、页面（略）
index.html
discuss-detail.html
discuss.js

4、我收到的赞的功能

1、RedisKeyUtil中增加新的key

  1. public class RedisKeyUtil {
  3.     private static final String SPLIT = ":";
  4.     private static final String PREFIX_ENTITY_LIKE = "like:entity";
  5.     private static final String PREFIX_USER_LIKE = "like:user";
  7.     // 某个实体的赞
  8.     // like:entity:entityType:entityId -> set(userId)
  9.     public static String getEntityLikeKey(int entityType, int entityId) {
  10.         return PREFIX_ENTITY_LIKE + SPLIT + entityType + SPLIT + entityId;
  11.     }
  13.     // 某个用户的赞
  14.     // like:user:userId -> int
  15.     public static String getUserLikeKey(int userId) {
  16.         return PREFIX_USER_LIKE + SPLIT + userId;
  17.     }
  18. }

2、LikeService

  1.  /**
  2.      * 点赞
  3.      * @param userId
  4.      * @param entityType
  5.      * @param entityId
  6.      */
  7.     public void like(int userId, int entityType, int entityId, int entityUserId) {
  8.         redisTemplate.execute(new SessionCallback() {
  9.             @Override
  10.             public Object execute(RedisOperations operations) throws DataAccessException {
  11.                 String entityLikeKey = RedisKeyUtil.getEntityLikeKey(entityType, entityId);
  12.                 String userLikeKey = RedisKeyUtil.getUserLikeKey(entityUserId);
  14.                 boolean isMember = operations.opsForSet().isMember(entityLikeKey, userId);
  16.                 operations.multi();
  18.                 if (isMember) {
  19.                     operations.opsForSet().remove(entityLikeKey, userId);
  20.                     operations.opsForValue().decrement(userLikeKey);
  21.                 } else {
  22.                     operations.opsForSet().add(entityLikeKey, userId);
  23.                     operations.opsForValue().increment(userLikeKey);
  24.                 }
  25.                 return operations.exec();
  26.             }
  27.         });
  28.     }
  30.   /**
  31.      * 查询某个用户获得的赞
  32.      * @param userId
  33.      * @return
  34.      */
  35.     public int findUserLikeCount(int userId) {
  36.         String userLikeKey = RedisKeyUtil.getUserLikeKey(userId);
  37.         Integer count = (Integer) redisTemplate.opsForValue().get(userLikeKey);
  38.         return count == null ? 0 : count.intValue();
  39.     }

3、LikeController

  1.  public String like(int entityType, int entityId,int entityUserId) {
  2.         User user = hostHolder.getUser();
  4.         // 点赞
  5.         likeService.like(user.getId(), entityType, entityId, entityUserId);

4、UserController

  1. /**
  2.      * 个人主页接口
  3.      * @param userId
  4.      * @param model
  5.      * @return
  6.      */
  7.     @GetMapping("/profile/{userId}")
  8.     public String getProfilePage(@PathVariable("userId") int userId, Model model) {
  9.         User user = userService.selectUserById(userId);
  10.         if (user == null) {
  11.             throw new RuntimeException("该用户不存在!");
  12.         }
  14.         // 用户
  15.         model.addAttribute("user", user);
  16.         // 点赞数量
  17.         int likeCount = likeService.findUserLikeCount(userId);
  18.         model.addAttribute("likeCount", likeCount);
  20.         return "/site/profile";
  21.     }

5、页面（略）
index.html
discuss-detail.html
discuss.js
profile.html

5、关注与被关注功能

1、RedisKeyUtil

  1.     private static final String PREFIX_FOLLOWEE = "followee";
  2.     private static final String PREFIX_FOLLOWER = "follower";
  4. // 某个用户关注的实体
  5.     // followee:userId:entityType -> zset(entityId,now)
  6.     public static String getFolloweeKey(int userId, int entityType) {
  7.         return PREFIX_FOLLOWEE + SPLIT + userId + SPLIT + entityType;
  8.     }
  10.     // 某个实体拥有的粉丝
  11.     // follower:entityType:entityId -> zset(userId,now)
  12.     public static String getFollowerKey(int entityType, int entityId) {
  13.         return PREFIX_FOLLOWER + SPLIT + entityType + SPLIT + entityId;
  14.     }

2、CommunityConstant

  1.   /**
  2.      * 实体类型: 用户
  3.      */
  4.     int ENTITY_TYPE_USER = 3;

3、FollowService

  1. @Service
  2. public class FollowService {
  4.     @Autowired
  5.     private RedisTemplate redisTemplate;
  7.     /**
  8.      * 关注
  9.      * @param userId
  10.      * @param entityType
  11.      * @param entityId
  12.      */
  13.     public void follow(int userId, int entityType, int entityId) {
  14.         redisTemplate.execute(new SessionCallback() {
  15.             @Override
  16.             public Object execute(RedisOperations operations) throws DataAccessException {
  17.                 String followeeKey = RedisKeyUtil.getFolloweeKey(userId, entityType);
  18.                 String followerKey = RedisKeyUtil.getFollowerKey(entityType, entityId);
  20.                 operations.multi();
  22.                 operations.opsForZSet().add(followeeKey, entityId, System.currentTimeMillis());
  23.                 operations.opsForZSet().add(followerKey, userId, System.currentTimeMillis());
  25.                 return operations.exec();
  26.             }
  27.         });
  28.     }
  30.     /**
  31.      * 取消关注
  32.      * @param userId
  33.      * @param entityType
  34.      * @param entityId
  35.      */
  36.     public void unfollow(int userId, int entityType, int entityId) {
  37.         redisTemplate.execute(new SessionCallback() {
  38.             @Override
  39.             public Object execute(RedisOperations operations) throws DataAccessException {
  40.                 String followeeKey = RedisKeyUtil.getFolloweeKey(userId, entityType);
  41.                 String followerKey = RedisKeyUtil.getFollowerKey(entityType, entityId);
  43.                 operations.multi();
  45.                 operations.opsForZSet().remove(followeeKey, entityId);
  46.                 operations.opsForZSet().remove(followerKey, userId);
  48.                 return operations.exec();
  49.             }
  50.         });
  51.     }
  53.     /**
  54.      * 查询关注的实体的数量
  55.      * @param userId
  56.      * @param entityType
  57.      * @return
  58.      */
  59.     public long findFolloweeCount(int userId, int entityType) {
  60.         String followeeKey = RedisKeyUtil.getFolloweeKey(userId, entityType);
  61.         return redisTemplate.opsForZSet().zCard(followeeKey);
  62.     }
  64.     /**
  65.      * 查询实体的粉丝的数量
  66.      * @param entityType
  67.      * @param entityId
  68.      * @return
  69.      */
  70.     public long findFollowerCount(int entityType, int entityId) {
  71.         String followerKey = RedisKeyUtil.getFollowerKey(entityType, entityId);
  72.         return redisTemplate.opsForZSet().zCard(followerKey);
  73.     }
  75.     /**
  76.      * 查询当前用户是否已关注该实体
  77.      * @param userId
  78.      * @param entityType
  79.      * @param entityId
  80.      * @return
  81.      */
  82.     public boolean hasFollowed(int userId, int entityType, int entityId) {
  83.         String followeeKey = RedisKeyUtil.getFolloweeKey(userId, entityType);
  84.         return redisTemplate.opsForZSet().score(followeeKey, entityId) != null;
  85.     }
  87. }

4、UserController实现CommuniyuConstant接口

  1.          // 关注数量
  2.         long followeeCount = followService.findFolloweeCount(userId, ENTITY_TYPE_USER);
  3.         model.addAttribute("followeeCount", followeeCount);
  4.         // 粉丝数量
  5.         long followerCount = followService.findFollowerCount(ENTITY_TYPE_USER, userId);
  6.         model.addAttribute("followerCount", followerCount);
  7.         // 是否已关注
  8.         boolean hasFollowed = false;
  9.         if (hostHolder.getUser() != null) {
  10.             hasFollowed = followService.hasFollowed(hostHolder.getUser().getId(), ENTITY_TYPE_USER, userId);
  11.         }
  12.         model.addAttribute("hasFollowed", hasFollowed);

5、FollowController

  1. @Controller
  2. public class FollowController {
  4.     @Autowired
  5.     private FollowService followService;
  6.     @Autowired
  7.     private HostHolder hostHolder;
  9.     /**
  10.      * 关注接口
  11.      * @param entityType
  12.      * @param entityId
  13.      * @return
  14.      */
  15.     @RequestMapping(path = "/follow", method = RequestMethod.POST)
  16.     @ResponseBody
  17.     public String follow(int entityType, int entityId) {
  18.         User user = hostHolder.getUser();
  20.         followService.follow(user.getId(), entityType, entityId);
  22.         return CommunityUtil.getJSONString(0, "已关注!");
  23.     }
  25.     /**
  26.      * 取消关注接口
  27.      * @param entityType
  28.      * @param entityId
  29.      * @return
  30.      */
  31.     @RequestMapping(path = "/unfollow", method = RequestMethod.POST)
  32.     @ResponseBody
  33.     public String unfollow(int entityType, int entityId) {
  34.         User user = hostHolder.getUser();
  36.         followService.unfollow(user.getId(), entityType, entityId);
  38.         return CommunityUtil.getJSONString(0, "已取消关注!");
  39.     }
  40. }

6、页面（略）
index.html
profile.html
discuss.html

6、关注列表与粉丝列表功能

• 业务层

  • 查询某个用户关注的人，支持分页。
  • 查询某个用户的粉丝，支持分页。

• 表现层

  • 处理“查询关注的人”、“查询粉丝”请求。
  • 编写“查询关注的人”、“查询粉丝”模板。

1、FollowService

  1.  /**
  2.      * 查询某用户关注的人
  3.      * @param userId
  4.      * @param offset
  5.      * @param limit
  6.      * @return
  7.      */
  8.     public List<Map<String, Object>> findFollowees(int userId, int offset, int limit) {
  9.         String followeeKey = RedisKeyUtil.getFolloweeKey(userId, ENTITY_TYPE_USER);
  10.         Set<Integer> targetIds = redisTemplate.opsForZSet().reverseRange(followeeKey, offset, offset + limit - 1);
  12.         if (targetIds == null) {
  13.             return null;
  14.         }
  16.         List<Map<String, Object>> list = new ArrayList<>();
  17.         for (Integer targetId : targetIds) {
  18.             Map<String, Object> map = new HashMap<>();
  19.             User user = userService.selectUserById(targetId);
  20.             map.put("user", user);
  21.             Double score = redisTemplate.opsForZSet().score(followeeKey, targetId);
  22.             map.put("followTime", new Date(score.longValue()));
  23.             list.add(map);
  24.         }
  26.         return list;
  27.     }
  29.     /**
  30.      * 查询某用户的粉丝
  31.      * @param userId
  32.      * @param offset
  33.      * @param limit
  34.      * @return
  35.      */
  36.     public List<Map<String, Object>> findFollowers(int userId, int offset, int limit) {
  37.         String followerKey = RedisKeyUtil.getFollowerKey(ENTITY_TYPE_USER, userId);
  38.         Set<Integer> targetIds = redisTemplate.opsForZSet().reverseRange(followerKey, offset, offset + limit - 1);
  40.         if (targetIds == null) {
  41.             return null;
  42.         }
  44.         List<Map<String, Object>> list = new ArrayList<>();
  45.         for (Integer targetId : targetIds) {
  46.             Map<String, Object> map = new HashMap<>();
  47.             User user = userService.selectUserById(targetId);
  48.             map.put("user", user);
  49.             Double score = redisTemplate.opsForZSet().score(followerKey, targetId);
  50.             map.put("followTime", new Date(score.longValue()));
  51.             list.add(map);
  52.         }
  54.         return list;
  55.     }

2、FollowController

  1.  /**
  2.      * 查询关注列表接口
  3.      * @param userId
  4.      * @param page
  5.      * @param model
  6.      * @return
  7.      */
  8.     @GetMapping("/followees/{userId}")
  9.     public String getFollowees(@PathVariable("userId") int userId, Page page, Model model) {
  10.         User user = userService.selectUserById(userId);
  11.         if (user == null) {
  12.             throw new RuntimeException("该用户不存在!");
  13.         }
  14.         model.addAttribute("user", user);
  16.         page.setLimit(5);
  17.         page.setPath("/followees/" + userId);
  18.         page.setRows((int) followService.findFolloweeCount(userId, ENTITY_TYPE_USER));
  20.         List<Map<String, Object>> userList = followService.findFollowees(userId, page.getOffset(), page.getLimit());
  21.         if (userList != null) {
  22.             for (Map<String, Object> map : userList) {
  23.                 User u = (User) map.get("user");
  24.                 map.put("hasFollowed", hasFollowed(u.getId()));
  25.             }
  26.         }
  27.         model.addAttribute("users", userList);
  29.         return "/site/followee";
  30.     }
  32.     /**
  33.      * 查询粉丝列表接口
  34.      * @param userId
  35.      * @param page
  36.      * @param model
  37.      * @return
  38.      */
  39.     @GetMapping("/followers/{userId}")
  40.     public String getFollowers(@PathVariable("userId") int userId, Page page, Model model) {
  41.         User user = userService.selectUserById(userId);
  42.         if (user == null) {
  43.             throw new RuntimeException("该用户不存在!");
  44.         }
  45.         model.addAttribute("user", user);
  47.         page.setLimit(5);
  48.         page.setPath("/followers/" + userId);
  49.         page.setRows((int) followService.findFollowerCount(ENTITY_TYPE_USER, userId));
  51.         List<Map<String, Object>> userList = followService.findFollowers(userId, page.getOffset(), page.getLimit());
  52.         if (userList != null) {
  53.             for (Map<String, Object> map : userList) {
  54.                 User u = (User) map.get("user");
  55.                 map.put("hasFollowed", hasFollowed(u.getId()));
  56.             }
  57.         }
  58.         model.addAttribute("users", userList);
  60.         return "/site/follower";
  61.     }
  63.     private boolean hasFollowed(int userId) {
  64.         if (hostHolder.getUser() == null) {
  65.             return false;
  66.         }
  68.         return followService.hasFollowed(hostHolder.getUser().getId(), ENTITY_TYPE_USER, userId);
  69.     }

3、页面（略）
discuss-detail.html
followee.html
follower.html
profile.html

7、优化登录模块

使用Redis存储验证码

  • 验证码需要频繁的访问与刷新，对性能要求较高。
  • 验证码不需永久保存，通常在很短的时间后就会失效。

分布式部署时，存在Session共享的问题。
• 使用Redis存储登录凭证
处理每次请求时，都要查询用户的登录凭证，访问的频率非常高。
• 使用Redis缓存用户信息
1、RedisKeyUtil
2、UserService
3、LoginTicketMapper
4、LoginController