此 demo 主要演示了 Spring Boot 如何整合 redis,操作redis中的数据,并使用redis缓存数据。连接池使用 Lettuce。
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<artifactId>spring-boot-demo-cache-redis</artifactId>
<version>1.0.0-SNAPSHOT</version>
<packaging>jar</packaging>
<name>spring-boot-demo-cache-redis</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>com.xkcoding</groupId>
<artifactId>spring-boot-demo</artifactId>
<version>1.0.0-SNAPSHOT</version>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<!-- 对象池,使用redis时必须引入 -->
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-pool2</artifactId>
</dependency>
<!-- 引入 jackson 对象json转换 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-json</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
</dependency>
<dependency>
<groupId>cn.hutool</groupId>
<artifactId>hutool-all</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
<build>
<finalName>spring-boot-demo-cache-redis</finalName>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
spring:
redis:
host: localhost
# 连接超时时间(记得添加单位,Duration)
timeout: 10000ms
# Redis默认情况下有16个分片,这里配置具体使用的分片
# database: 0
lettuce:
pool:
# 连接池最大连接数(使用负值表示没有限制) 默认 8
max-active: 8
# 连接池最大阻塞等待时间(使用负值表示没有限制) 默认 -1
max-wait: -1ms
# 连接池中的最大空闲连接 默认 8
max-idle: 8
# 连接池中的最小空闲连接 默认 0
min-idle: 0
cache:
# 一般来说是不用配置的,Spring Cache 会根据依赖的包自行装配
type: redis
logging:
level:
com.xkcoding: debug
/**
* <p>
* redis配置
* </p>
*
* @author yangkai.shen
* @date Created in 2018-11-15 16:41
*/
@Configuration
@AutoConfigureAfter(RedisAutoConfiguration.class)
@EnableCaching
public class RedisConfig {
/**
* 默认情况下的模板只能支持RedisTemplate<String, String>,也就是只能存入字符串,因此支持序列化
*/
@Bean
public RedisTemplate<String, Serializable> redisCacheTemplate(LettuceConnectionFactory redisConnectionFactory) {
RedisTemplate<String, Serializable> template = new RedisTemplate<>();
template.setKeySerializer(new StringRedisSerializer());
template.setValueSerializer(new GenericJackson2JsonRedisSerializer());
template.setConnectionFactory(redisConnectionFactory);
return template;
}
/**
* 配置使用注解的时候缓存配置,默认是序列化反序列化的形式,加上此配置则为 json 形式
*/
@Bean
public CacheManager cacheManager(RedisConnectionFactory factory) {
// 配置序列化
RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig();
RedisCacheConfiguration redisCacheConfiguration = config.serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(new StringRedisSerializer())).serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(new GenericJackson2JsonRedisSerializer()));
return RedisCacheManager.builder(factory).cacheDefaults(redisCacheConfiguration).build();
}
}
/**
* <p>
* UserService
* </p>
*
* @author yangkai.shen
* @date Created in 2018-11-15 16:45
*/
@Service
@Slf4j
public class UserServiceImpl implements UserService {
/**
* 模拟数据库
*/
private static final Map<Long, User> DATABASES = Maps.newConcurrentMap();
/**
* 初始化数据
*/
static {
DATABASES.put(1L, new User(1L, "user1"));
DATABASES.put(2L, new User(2L, "user2"));
DATABASES.put(3L, new User(3L, "user3"));
}
/**
* 保存或修改用户
*
* @param user 用户对象
* @return 操作结果
*/
@CachePut(value = "user", key = "#user.id")
@Override
public User saveOrUpdate(User user) {
DATABASES.put(user.getId(), user);
log.info("保存用户【user】= {}", user);
return user;
}
/**
* 获取用户
*
* @param id key值
* @return 返回结果
*/
@Cacheable(value = "user", key = "#id")
@Override
public User get(Long id) {
// 我们假设从数据库读取
log.info("查询用户【id】= {}", id);
return DATABASES.get(id);
}
/**
* 删除
*
* @param id key值
*/
@CacheEvict(value = "user", key = "#id")
@Override
public void delete(Long id) {
DATABASES.remove(id);
log.info("删除用户【id】= {}", id);
}
}
主要测试使用
RedisTemplate
操作Redis
中的数据:
- opsForValue:对应 String(字符串)
- opsForZSet:对应 ZSet(有序集合)
- opsForHash:对应 Hash(哈希)
- opsForList:对应 List(列表)
- opsForSet:对应 Set(集合)
- opsForGeo:** 对应 GEO(地理位置)
/**
* <p>
* Redis测试
* </p>
*
* @author yangkai.shen
* @date Created in 2018-11-15 17:17
*/
@Slf4j
public class RedisTest extends SpringBootDemoCacheRedisApplicationTests {
@Autowired
private StringRedisTemplate stringRedisTemplate;
@Autowired
private RedisTemplate<String, Serializable> redisCacheTemplate;
/**
* 测试 Redis 操作
*/
@Test
public void get() {
// 测试线程安全,程序结束查看redis中count的值是否为1000
ExecutorService executorService = Executors.newFixedThreadPool(1000);
IntStream.range(0, 1000).forEach(i -> executorService.execute(() -> stringRedisTemplate.opsForValue().increment("count", 1)));
stringRedisTemplate.opsForValue().set("k1", "v1");
String k1 = stringRedisTemplate.opsForValue().get("k1");
log.debug("【k1】= {}", k1);
// 以下演示整合,具体Redis命令可以参考官方文档
String key = "xkcoding:user:1";
redisCacheTemplate.opsForValue().set(key, new User(1L, "user1"));
// 对应 String(字符串)
User user = (User) redisCacheTemplate.opsForValue().get(key);
log.debug("【user】= {}", user);
}
}
主要测试使用Redis缓存是否起效
/**
* <p>
* Redis - 缓存测试
* </p>
*
* @author yangkai.shen
* @date Created in 2018-11-15 16:53
*/
@Slf4j
public class UserServiceTest extends SpringBootDemoCacheRedisApplicationTests {
@Autowired
private UserService userService;
/**
* 获取两次,查看日志验证缓存
*/
@Test
public void getTwice() {
// 模拟查询id为1的用户
User user1 = userService.get(1L);
log.debug("【user1】= {}", user1);
// 再次查询
User user2 = userService.get(1L);
log.debug("【user2】= {}", user2);
// 查看日志,只打印一次日志,证明缓存生效
}
/**
* 先存,再查询,查看日志验证缓存
*/
@Test
public void getAfterSave() {
userService.saveOrUpdate(new User(4L, "测试中文"));
User user = userService.get(4L);
log.debug("【user】= {}", user);
// 查看日志,只打印保存用户的日志,查询是未触发查询日志,因此缓存生效
}
/**
* 测试删除,查看redis是否存在缓存数据
*/
@Test
public void deleteUser() {
// 查询一次,使redis中存在缓存数据
userService.get(1L);
// 删除,查看redis是否存在缓存数据
userService.delete(1L);
}
}
- spring-data-redis 官方文档:https://docs.spring.io/spring-data/redis/docs/2.0.1.RELEASE/reference/html/
- redis 文档:https://redis.io/documentation
- redis 中文文档:http://www.redis.cn/commands.html