这一篇介绍Spring Boot使用Redis实现session共享,需要springboot实战完整视频教程的,点击这里!
Redis是一个缓存消息中间件及具有丰富特性的键值存储系统。Spring Boot为Jedis客户端库和由Spring Data Redis提供的基于Jedis客户端的抽象提供自动配置。spring-boot-starter-redis'Starter POM'为收集依赖提供一种便利的方式。
引入spring-boot-starter-redis,在pom.xml配置文件中增加配置如下(基于之前章节“Spring Boot 构建框架”中的pom.xml文件):
- <dependency>
- <groupId>org.springframework.boot</groupId>
- <artifactId>spring-boot-starter-redis</artifactId>
- </dependency>
可以注入一个自动配置的RedisConnectionFactory,StringRedisTemplate或普通的跟其他Spring Bean相同的RedisTemplate实例。默认情况下,这个实例将尝试使用localhost:6379连接Redis服务器。
- @Component
- public class MyBean {
- private StringRedisTemplate template;
- @Autowired
- public MyBean(StringRedisTemplate template) {
- this.template = template;
- }
- // ...
- }
如果添加一个自己的任何自动配置类型的@Bean,它将替换默认的(除了RedisTemplate的情况,它是根据bean的名称'redisTemplate'而不是它的类型进行排除的)。如果在classpath路径下存在commons-pool2,默认会获得一个连接池工厂。
应用使用Redis案例
添加配置文件,配置内容如下:
- # REDIS (RedisProperties)
- # Redis服务器地址
- spring.redis.host=192.168.0.58
- # Redis服务器连接端口
- spring.redis.port=6379
- # 连接超时时间(毫秒)
- spring.redis.timeout=0
redis配置类,具体代码如下:
- import org.springframework.boot.context.properties.ConfigurationProperties;
- import org.springframework.stereotype.Component;
- @Component
- @ConfigurationProperties(prefix = "spring.redis")
- public class RedisConn {
- private String host;
- private int port;
- private int timeout;
- public String getHost() {
- return host;
- }
- public void setHost(String host) {
- this.host = host;
- }
- public int getPort() {
- return port;
- }
- public void setPort(int port) {
- this.port = port;
- }
- public int getTimeout() {
- return timeout;
- }
- public void setTimeout(int timeout) {
- this.timeout = timeout;
- }
- @Override
- public String toString() {
- return "Redis [localhost=" + host + ", port=" + port + ", timeout=" + timeout + "]";
- }
- }
注意:在RedisConn类中注解@ConfigurationProperties(prefix = "spring.Redis")的作用是读取springboot的默认配置文件信息中以spring.redis开头的信息。
配置cache类
- import java.lang.reflect.Method;
- import java.util.HashMap;
- import java.util.Map;
- import org.springframework.beans.factory.annotation.Autowired;
- import org.springframework.beans.factory.annotation.Value;
- import org.springframework.cache.CacheManager;
- import org.springframework.cache.annotation.CachingConfigurerSupport;
- import org.springframework.cache.annotation.EnableCaching;
- import org.springframework.cache.interceptor.KeyGenerator;
- import org.springframework.context.annotation.Bean;
- import org.springframework.context.annotation.ComponentScan;
- import org.springframework.context.annotation.Configuration;
- import org.springframework.context.annotation.PropertySource;
- import org.springframework.data.redis.cache.RedisCacheManager;
- import org.springframework.data.redis.connection.RedisConnectionFactory;
- import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
- import org.springframework.data.redis.core.RedisTemplate;
- import org.springframework.data.redis.core.StringRedisTemplate;
- import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
- import org.springframework.stereotype.Component;
- import com.cachemodle.RedisConn;
- import com.fasterxml.jackson.annotation.JsonAutoDetect;
- import com.fasterxml.jackson.annotation.PropertyAccessor;
- import com.fasterxml.jackson.databind.ObjectMapper;
- /**
- *
- * @author sandsa redis cache service
- *
- */
- @Configuration
- @EnableCaching
- public class RedisConfig extends CachingConfigurerSupport {
- @Autowired
- private RedisConn redisConn;
- /**
- * 生产key的策略
- *
- * @return
- */
- @Bean
- @Override
- public KeyGenerator keyGenerator() {
- return new KeyGenerator() {
- @Override
- public Object generate(Object target, Method method, Object... params) {
- StringBuilder sb = new StringBuilder();
- sb.append(target.getClass().getName());
- sb.append(method.getName());
- for (Object obj : params) {
- sb.append(obj.toString());
- }
- return sb.toString();
- }
- };
- }
- /**
- * 管理缓存
- *
- * @param redisTemplate
- * @return
- */
- @SuppressWarnings("rawtypes")
- @Bean
- public CacheManager CacheManager(RedisTemplate redisTemplate) {
- RedisCacheManager rcm = new RedisCacheManager(redisTemplate);
- // 设置cache过期时间,时间单位是秒
- rcm.setDefaultExpiration(60);
- Map<String, Long> map = new HashMap<String, Long>();
- map.put("test", 60L);
- rcm.setExpires(map);
- return rcm;
- }
- /**
- * redis 数据库连接池
- * @return
- */
- @Bean
- public JedisConnectionFactory redisConnectionFactory() {
- JedisConnectionFactory factory = new JedisConnectionFactory();
- factory.setHostName(redisConn.getHost());
- factory.setPort(redisConn.getPort());
- factory.setTimeout(redisConn.getTimeout()); // 设置连接超时时间
- return factory;
- }
- /**
- * redisTemplate配置
- *
- * @param factory
- * @return
- */
- @SuppressWarnings({ "rawtypes", "unchecked" })
- @Bean
- public RedisTemplate<String, String> redisTemplate(RedisConnectionFactory factory) {
- StringRedisTemplate template = new StringRedisTemplate(factory);
- Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
- ObjectMapper om = new ObjectMapper();
- om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
- om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
- jackson2JsonRedisSerializer.setObjectMapper(om);
- template.setValueSerializer(jackson2JsonRedisSerializer);
- template.afterPropertiesSet();
- return template;
- }
- }
分析:缓存类继承的是CachingConfigurerSupport,它把读取的配置文件信息的RedisConn类对象注入到这个类中。在这个类中keyGenerator()方法是key的生成策略,CacheManager()方法是缓存管理策略,redisConnectionFactory()是redis连接,redisTemplate()方法是redisTemplate配置信息,配置后使redis中能存储Java对象。
测试配置是否成功,实例:
- @RunWith(SpringJUnit4ClassRunner.class)
- @SpringApplicationConfiguration(Application.class)
- public class TestRedis {
- @Autowired
- private StringRedisTemplate stringRedisTemplate; // 处理字符串
- @Autowired
- private RedisTemplate redisTemplate; // 处理对象
- @Test
- public void test() throws Exception {
- stringRedisTemplate.opsForValue().set("yoodb", "123");
- Assert.assertEquals("123", stringRedisTemplate.opsForValue().get("yoodb"));
- }
- }
简单封装的Redis工具类,代码如下:
- import java.io.Serializable;
- import java.util.Set;
- import java.util.concurrent.TimeUnit;
- import org.springframework.beans.factory.annotation.Autowired;
- import org.springframework.data.redis.core.RedisTemplate;
- import org.springframework.data.redis.core.ValueOperations;
- import org.springframework.stereotype.Component;
- @Component
- public class RedisUtils {
- @SuppressWarnings("rawtypes")
- @Autowired
- private RedisTemplate redisTemplate;
- /**
- * 批量删除对应的value
- *
- * @param keys
- */
- public void remove(final String... keys) {
- for (String key : keys) {
- remove(key);
- }
- }
- /**
- * 批量删除key
- *
- * @param pattern
- */
- @SuppressWarnings("unchecked")
- public void removePattern(final String pattern) {
- Set<Serializable> keys = redisTemplate.keys(pattern);
- if (keys.size() > 0)
- redisTemplate.delete(keys);
- }
- /**
- * 删除对应的value
- *
- * @param key
- */
- @SuppressWarnings("unchecked")
- public void remove(final String key) {
- if (exists(key)) {
- redisTemplate.delete(key);
- }
- }
- /**
- * 判断缓存中是否有对应的value
- *
- * @param key
- * @return
- */
- @SuppressWarnings("unchecked")
- public boolean exists(final String key) {
- return redisTemplate.hasKey(key);
- }
- /**
- * 读取缓存
- *
- * @param key
- * @return
- */
- @SuppressWarnings("unchecked")
- public Object get(final String key) {
- Object result = null;
- ValueOperations<Serializable, Object> operations = redisTemplate.opsForValue();
- result = operations.get(key);
- return result;
- }
- /**
- * 写入缓存
- *
- * @param key
- * @param value
- * @return
- */
- @SuppressWarnings("unchecked")
- public boolean set(final String key, Object value) {
- boolean result = false;
- try {
- ValueOperations<Serializable, Object> operations = redisTemplate.opsForValue();
- operations.set(key, value);
- result = true;
- } catch (Exception e) {
- e.printStackTrace();
- }
- return result;
- }
- /**
- * 写入缓存
- *
- * @param key
- * @param value
- * @return
- */
- @SuppressWarnings("unchecked")
- public boolean set(final String key, Object value, Long expireTime) {
- boolean result = false;
- try {
- ValueOperations<Serializable, Object> operations = redisTemplate.opsForValue();
- operations.set(key, value);
- redisTemplate.expire(key, expireTime, TimeUnit.SECONDS);
- result = true;
- } catch (Exception e) {
- e.printStackTrace();
- }
- return result;
- }
- }
查询数据库时自动使用缓存,根据方法生成缓存,参考代码如下:
- @Service
- public class UserService {
- @Cacheable(value = "redis-key")
- public UserInfo getUserInfo(Long id, String sex, int age, String name) {
- System.out.println("无缓存时调用----数据库查询");
- return new UserInfo(id, sex, age, name);
- }
- }
注意:value的值就是缓存到redis中的key,此key是需要自己在进行增加缓存信息时定义的key,用于标识唯一性的。
Session 共享
分布式系统中session共享有很多不错的解决方案,其中托管到缓存中是比较常见的方案之一,下面利用Session-spring-session-data-redis实现session共享。
引入依赖,在pom.xml配置文件中增加如下内容:
- <dependency>
- <groupId>org.springframework.session</groupId>
- <artifactId>spring-session-data-redis</artifactId>
- </dependency>
Session配置,具体代码如下:
- @Configuration
- @EnableRedisHttpSession(maxInactiveIntervalInSeconds = 86400*30)
- public class SessionConfig {
- }
maxInactiveIntervalInSeconds: 设置Session失效时间,使用Redis Session之后,原Spring Boot的server.session.timeout属性不再生效。
测试实例,具体代码如下:
- @RequestMapping("uid")
- String uid(HttpSession session) {
- UUID uid = (UUID) session.getAttribute("uid");
- if (uid == null) {
- uid = UUID.randomUUID();
- }
- session.setAttribute("uid", uid);
- return session.getId();
- }
登录redis服务端,输入命令keys 'session*',查看缓存是否成功。
来源: https://mp.weixin.qq.com/s?__biz=MzI4Njc5NjM1NQ==&mid=2247484135&idx=2&sn=187759bac503e75fde0c520b75508ae5&chksm=ebd63dcbdca1b4dda788fcae43c8579bb7f3e7cdb60edbea9d9725dec91dbfa54c07c4915221#rd