springboot整合Redis

springboot整合Redis 前言

Redis是目前使用的非常廣泛的記憶體資料庫，相比memcached，它支援更加豐富的資料類型。本來簡要介紹在springboot中使用redis的方法。 如何使用。

1、引入spring-boot-starter-redis

<!-- redis --><dependency>    <groupId>org.springframework.boot</groupId>    <artifactId>spring-boot-starter-data-redis</artifactId></dependency>

2、在application.properties增加Redis的配置

# 使用的資料庫（0-15），預設為0spring.redis.database=0  # Redis伺服器位址spring.redis.host=127.0.0.1# Redis伺服器串連連接埠spring.redis.port=6379  # Redis伺服器串連密碼（預設為空白）spring.redis.password=  

3、使用

@Autowiredprivate StringRedisTemplate stringRedisTemplate;@RequestMapping(value = "/redis/{key}/{value}",method = RequestMethod.GET)@ResponseBodypublic String redisTest(@PathVariable String key,@PathVariable String value) {    String redisValue = stringRedisTemplate.opsForValue().get(key);    if (StringUtils.isEmpty(redisValue)) {        stringRedisTemplate.opsForValue().set(key,value);        return "操作成功。";    }    if (!redisValue.equals(value)) {        stringRedisTemplate.opsForValue().set(key,value);        return "操作成功。";    }    return String.format("redis中已存在[key=%s,value=%s]的資料。",key,value);}

隨便寫的一個例子。

4、Sentinel模式配置
上面的是單機的一個配置，如果是主從，參考：

#redis配置spring.redis.database=0spring.redis.password=systemspring.redis.pool.max-idle=10spring.redis.pool.min-idle=0spring.redis.pool.max-active=10spring.redis.pool.max-wait=-1spring.redis.sentinel.master=mymasterspring.redis.sentinel.nodes=192.168.74.135:26379,192.168.74.136:26379

5、redis的全部配置：

# REDIS (RedisProperties)spring.redis.cluster.max-redirects= # Maximum number of redirects to follow when executing commands across the cluster.spring.redis.cluster.nodes= # Comma-separated list of "host:port" pairs to bootstrap from.spring.redis.database=0 # Database index used by the connection factory.spring.redis.url= # Connection URL, will override host, port and password (user will be ignored), e.g. redis://user:password@example.com:6379spring.redis.host=localhost # Redis server host.spring.redis.password= # Login password of the redis server.spring.redis.ssl=false # Enable SSL support.spring.redis.pool.max-active=8 # Max number of connections that can be allocated by the pool at a given time. Use a negative value for no limit.spring.redis.pool.max-idle=8 # Max number of "idle" connections in the pool. Use a negative value to indicate an unlimited number of idle connections.spring.redis.pool.max-wait=-1 # Maximum amount of time (in milliseconds) a connection allocation should block before throwing an exception when the pool is exhausted. Use a negative value to block indefinitely.spring.redis.pool.min-idle=0 # Target for the minimum number of idle connections to maintain in the pool. This setting only has an effect if it is positive.spring.redis.port=6379 # Redis server port.spring.redis.sentinel.master= # Name of Redis server.spring.redis.sentinel.nodes= # Comma-separated list of host:port pairs.spring.redis.timeout=0 # Connection timeout in milliseconds.

6、使用redis自動快取資料
可以把一些經常查詢的資料放到redis緩衝起來，不用每次都查詢資料庫。
上面是手動快取到redis，這裡介紹一下如何自動資料緩衝到redis。

a.增加一個redis的配置類：

@Configuration@EnableCachingpublic class RedisConfig{    @Bean    public KeyGenerator redisKeyGenerator(){        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();            }        };    }    @Bean    public CacheManager cacheManager(            @SuppressWarnings("rawtypes") RedisTemplate redisTemplate) {        return new RedisCacheManager(redisTemplate);    }    @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;    }}

b.在需要緩衝的service方法上加上註解：

@Cacheable(value = "userCache")public TUser findById(String id) {    return this.userRepository.findOne(id);}

這樣，就只有redis沒有相應的Key的時候才會查詢資料庫。

我們看下redis：

圖中，redis的key就是你的參數。