第二篇：SpringBoot高级-整合redis作为缓存
Redis简介 Redis 是一个开源（BSD许可）的，内存中的数据结构存储系统，它可以用作数据库、缓存和消息中间件。 搭建Redis环境 1. 安装redis：使用Docker （使用docker中国加速 [root@localhost ~]# docker pull registry.docker-cn.com/library/redis Using default tag: latest latest: Pulling from library/redis 683abbb4ea60: Already exists 259238e792d8: Pull complete 78399601c709: Pull complete f397da474601: Pull complete c57de4edc390: Pull complete b2ea05c9d9a1: Pull complete Digest: sha256:5534b92530acc653f0721ebfa14f31bc718f68bf9070cbba25bb00bc7aacfabb Status: Downloaded newer image for registry.docker-cn.com/library/redis:latest 使用docker images查询 [root@localhost ~]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE registry.docker-cn.com/library/redis latest 71a81cb279e3 7 days ago 83.4MB mysql 5.7 66bc0f66b7af 7 days ago 372MB 使用docker启动redis [root@localhost ~]# docker run -d -p 6379:6379 --name myredis registry.docker-cn.com/library/redis ba65a5f3fc5c996ea23582a0cfeb0275be759c1a19fc920dd6f513127b5c9738 使用docker ps -a 查询运行情况 [root@localhost ~]# docker ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES ba65a5f3fc5c registry.docker-cn.com/library/redis "docker-entrypoint..." About a minute ago Up About a minute 0.0.0.0:6379->6379/tcp myredis 2. 引入redis依赖包 <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency> 3. 配置redis # redis配置项 # Redis数据库索引（默认为0） spring.redis.database=0 # Redis服务器地址 spring.redis.host=192.168.43.53 # Redis服务器连接端口 spring.redis.port=6379 # Redis服务器连接密码（默认为空） spring.redis.password= 引入redis依赖包后系统就会自动引入RedisAutoConfiguration完成redis相关配置。其中就包括自动配置好了，RedisTemplate 、StringRedisTemplage。我们就可以在项目中直接使用。4. 编写redis测试方法 Redis 常见的五大数据类型： String(字符串）、List(列表）、Set(集合)、Hash(散列)/ ZSet(有序集合) stringRedisTemplate.opsForValue()：【String（字符串）】 stringRedisTemplate.opsForList()：【List（列表）】 stringRedisTemplate.opsForSet()：【Set（集合）】 stringRedisTemplate.opsForHash()：【Hash（散列）】 stringRedisTemplate.opsForZSet():【有序集合】 /** * Redis 常见的五大数据类型 * String(字符串）、List(列表）、Set(集合)、Hash(散列)/ ZSet(有序集合) */ @Autowired StringRedisTemplate stringRedisTemplate; @Autowired RedisTemplate redisTemplate; @Autowired RedisTemplate empRedisTemplate; // 自定义RedisTemplate @Test public void test01() { // 给redis存字符串数据 stringRedisTemplate.opsForValue().append("msg", "hello"); stringRedisTemplate.opsForList().leftPush("list", "v1"); stringRedisTemplate.opsForList().leftPush("list", "v2"); stringRedisTemplate.opsForList().leftPush("list", "v3"); stringRedisTemplate.opsForList().leftPush("list", "v4"); String msg = stringRedisTemplate.opsForValue().get("msg"); System.out.println(msg); // 给redis存对象数据 Employee employee = employeeMapper.getEmpById(1); // 这里使用默认的JDK序列化器：JdkSerializationRedisSerializer 将序列化后的数据保存到redis中 // 我们也可以自定义序列化器完成序列化存储 // 1. 自动手动将对象序列化为JSON字符串 // 2. 指定redisTemplate默认的序列化器 redisTemplate.opsForValue().set("emp", employee); empRedisTemplate.opsForValue().set("emp_json", employee); } 自定义序列化器： /** * Created by Administrator on 2018/7/4 0004. */ @Configuration public class MyRedisConfig { @Bean public RedisTemplate<Object, Employee> empRedisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException { RedisTemplate<Object, Employee> template = new RedisTemplate<Object, Employee>(); template.setConnectionFactory(redisConnectionFactory); Jackson2JsonRedisSerializer<Employee> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Employee.class); template.setDefaultSerializer(jackson2JsonRedisSerializer); return template; } } 使用Redis测试SpringBoot缓存 原理：系统使用CacheManager（ConcurrentMapCacheManager默认）来创建Cache组件，来完成缓存的CRUD操作。 默认情况下系统使用SimpleCacheConfiguration来引入ConcurrentMapCacheManager缓存管理器--》ConcurrentMapCache作为缓存组件 引入了redis的starter后容器中保存的是RedisCacheManager--》RedisCache作为缓存组件（通过操作redis缓存数据）， 默认保存数据 k-v 都是Object 默认利用jdk序列化保存 所以我们需要自定义CacheManager（使用我们自己的序列化器）： 重写RedisCacheConfiguration类中的方法： @Bean public RedisCacheManager cacheManager(RedisTemplate<Object, Object> redisTemplate) { RedisCacheManager cacheManager = new RedisCacheManager(redisTemplate); cacheManager.setUsePrefix(true); List cacheNames = this.cacheProperties.getCacheNames(); if(!cacheNames.isEmpty()) { cacheManager.setCacheNames(cacheNames); } return (RedisCacheManager)this.customizerInvoker.customize(cacheManager); } @Configuration public class MyRedisConfig { @Bean public RedisTemplate<Object, Employee> empRedisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException { RedisTemplate<Object, Employee> template = new RedisTemplate<>(); template.setConnectionFactory(redisConnectionFactory); Jackson2JsonRedisSerializer<Employee> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Employee.class); template.setDefaultSerializer(jackson2JsonRedisSerializer); return template; } @Bean public RedisTemplate<Object, Department> deptRedisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException { RedisTemplate<Object, Department> template = new RedisTemplate<>(); template.setConnectionFactory(redisConnectionFactory); Jackson2JsonRedisSerializer<Department> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Department.class); template.setDefaultSerializer(jackson2JsonRedisSerializer); return template; } @Bean public RedisCacheManager empCacheManager(RedisTemplate<Object, Employee> empRedisTemplate) { RedisCacheManager cacheManager = new RedisCacheManager(empRedisTemplate); // 使用前綴，默认使用cacheNames作为前缀 cacheManager.setUsePrefix(true); return cacheManager; } @Bean public RedisCacheManager deptCacheManager(RedisTemplate<Object, Department> deptRedisTemplate) { RedisCacheManager cacheManager = new RedisCacheManager(deptRedisTemplate); // 使用前綴，默认使用cacheNames作为前缀 cacheManager.setUsePrefix(true); return cacheManager; } @Primary @Bean public RedisCacheManager cacheManager(RedisTemplate<Object, Object> redisTemplate) { RedisCacheManager cacheManager = new RedisCacheManager(redisTemplate); cacheManager.setUsePrefix(true); return cacheManager; } } 在使用RedisCache时使用注解指定CacheManager: @Cacheable(cacheNames = {"emp"}, cacheManager = "empCacheManager") @Service public class EmployeeService { 手动编码操作缓存： @Autowired @Qualifier("empCacheManager") CacheManager empCacheManager; public Employee getEmp(Integer id){ Employee emp = employeeMapper.getEmpById(id); // 获取某个缓存组件 Cache empCache = empCacheManager.getCache("emp"); empCache.put("emp:1", emp); return emp; }
