标签:安装redis end 方便 style slf4j int centos 中大型 ntop
缓存现在几乎是所有中大型网站都在用的必杀技,合理的利用缓存不仅能够提升网站访问速度,还能大大降低数据库的压力。Redis提供了键过期功能,也提供了灵活的键淘汰策略,所以,现在Redis用在缓存的场合非常多。
之前有两篇博文(centos安装Redis 和 Redis五大数据类型的常用操作),分别介绍了Redis的安装和Redis的常用操作。今天主要介绍介绍springboot整合Redis。
现在公司做的项目都偏重论坛/社区/社交类产品,所以对Redis的实用场景主要集中在排行榜,最新/最热内容,Redis提供的有序集合数据类构能实现各种复杂的排行榜应用。还有点赞、踩、关注/被关注、共同好友等是社交网站的基本功能,社交网站的访问量通常来说比较大,而且传统的关系数据库类型不适合存储这种类型的数据,Redis提供的哈希、集合等数据结构能很方便的的实现这些功能。
还有很多应用场景,比如分布式会话和分布式锁(分布式锁感兴趣的可以看我之前的一篇文章《Java分布式锁,搞懂分布式锁实现看这篇文章就对了》)等等,总之越来越广泛。
1.1. 引入Redis
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency> <!--<dependency>--> <!--<groupId>redis.clients</groupId>--> <!--<artifactId>jedis</artifactId>--> <!--<version>2.9.0</version>--> <!--</dependency>-->
注意redis.clients是我本地调试测试用的,可以忽略。
1.2. 添加RedisCacheConfig
package com.demo.Redis; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.cache.annotation.EnableCaching; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.data.redis.connection.RedisConnectionFactory; import org.springframework.data.redis.core.StringRedisTemplate; import org.springframework.data.redis.listener.PatternTopic; import org.springframework.data.redis.listener.RedisMessageListenerContainer; import org.springframework.data.redis.listener.adapter.MessageListenerAdapter; import java.util.concurrent.CountDownLatch; /** * Created by toutou on 2019/1/20. */ @Configuration @EnableCaching public class RedisCacheConfig { @Bean RedisMessageListenerContainer container(RedisConnectionFactory connectionFactory, MessageListenerAdapter listenerAdapter) { RedisMessageListenerContainer container = new RedisMessageListenerContainer(); container.setConnectionFactory(connectionFactory); container.addMessageListener(listenerAdapter, new PatternTopic("chat")); return container; } @Bean MessageListenerAdapter listenerAdapter(Receiver receiver) { return new MessageListenerAdapter(receiver, "receiveMessage"); } @Bean Receiver receiver(CountDownLatch latch) { return new Receiver(latch); } @Bean CountDownLatch latch() { return new CountDownLatch(1); } @Bean StringRedisTemplate template(RedisConnectionFactory connectionFactory) { return new StringRedisTemplate(connectionFactory); } public class Receiver { private CountDownLatch latch; @Autowired public Receiver(CountDownLatch latch) { this.latch = latch; } public void receiveMessage(String message) { latch.countDown(); } } }
可以按需添加,也可以按需忽略。
1.3. 添加Redis配置,修改application.properties
# ----- Redis -------- #
# REDIS (RedisProperties)
# Redis数据库索引(默认为0)
spring.redis.database=0
# Redis服务器地址
spring.redis.host=10.168.11.129
# 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=
# 连接池最大连接数(使用负值表示没有限制)
spring.redis.pool.max-active=8
# 连接池最大阻塞等待时间(使用负值表示没有限制)
spring.redis.pool.max-wait=-1
# 连接池中的最大空闲连接
spring.redis.pool.max-idle=8
# 连接池中的最小空闲连接
spring.redis.pool.min-idle=0
# 连接超时时间(毫秒)
spring.redis.timeout=5000
1.4. 添加Service
package com.demo.service; import com.demo.pojo.UserDetails; /** * Created by toutou on 2018/10/15. */ public interface UserService { UserDetails getUserDetailsByUid(int uid); String getUserNameById(Integer uid); void setUserNameById(Integer uid, String userName); }
UserServiceImpl
package com.demo.service; import com.demo.dao.UserDetailsMapper; import com.demo.dao.UserPositionMapper; import com.demo.pojo.UserDetails; import com.demo.pojo.UserPosition; import com.google.common.base.Strings; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.redis.core.StringRedisTemplate; import org.springframework.stereotype.Service; import java.math.BigDecimal; import java.util.List; /** * Created by toutou on 2018/10/15. */ @Service public class UserServiceImpl implements UserService{ @Autowired UserDetailsMapper userDetailsMapper; @Autowired UserPositionMapper userPositionMapper; @Autowired StringRedisTemplate template; static final String KEY_USER_INFO__NAME = "com_demo_user_info_007_%s"; public String getUserNameById(Integer uid){ String userName = "未知用户"; try { userName = template.opsForValue().get(String.format(KEY_USER_INFO__NAME, uid)); if (Strings.isNullOrEmpty(userName)) { // Redis中没有就读数据库 UserDetails userDetails = getUserDetailsByUid(uid); if (userDetails != null && !Strings.isNullOrEmpty(userDetails.getCity())) { userName = userDetails.getCity(); } } }catch(Exception e){ System.out.println(e.toString()); } return userName; } public void setUserNameById(Integer uid, String userName){ template.opsForValue().set(String.format(KEY_USER_INFO__NAME, uid), userName); } public UserDetails getUserDetailsByUid(int uid){ return userDetailsMapper.getUserDetailsByUid(uid); } }
1.5. 添加RedisController
package com.demo.controller; import com.demo.service.UserService; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import redis.clients.jedis.Jedis; /** * Created by toutou on 2019/1/20. */ @RestController @Slf4j public class RedisController { @Autowired UserService userService; @RequestMapping(value = "/getusernamebyid") public String getUserNameById(Integer uid) { return userService.getUserNameById(uid); } @RequestMapping(value = "/setusernamebyid") public String setUserNameById(Integer uid, String uname) { userService.setUserNameById(uid, uname); return "设置成功"; } @RequestMapping(value = "/jedistest") public String jedisTest(){ // 创建一个jedis对象 Jedis jedis = new Jedis("ip", 6379); // 直接调用jedis对象的方法,方法名称和redis的命令一致 jedis.set("key1", "test01"); String key1 = jedis.get("key1"); System.out.println(key1 + " " + key1); // 关闭jedis jedis.close(); return key1; } }
标签:安装redis end 方便 style slf4j int centos 中大型 ntop
原文地址:https://www.cnblogs.com/toutou/p/spring_boot_redis.html