详解springboot整合redis

redis相信大家不会陌生，可以说是日常开发中用的最广泛的缓存工具，而springboot作为与Java的集成框架，适用面非常广泛，其中就包含了对redis的集成，网上针对此类文章个人搜索后感觉大多写的不够详细，所以小编决定自己写一篇，一来供自己学习，二来供读者探讨

redis配置类

@Configuration
public class RedisConfig {

    @Bean
    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) {
        RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(redisConnectionFactory);
        redisTemplate.setKeySerializer(RedisSerializer.string());
        redisTemplate.setValueSerializer(RedisSerializer.json());
        redisTemplate.setDefaultSerializer(RedisSerializer.json());
        return redisTemplate;
    }

    @Bean
    public RedisCacheManager redisCacheManager(RedisConnectionFactory redisConnectionFactory, CacheProperties cacheProperties) {
        RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig()
                // 设置缓存有效期为1天
                .entryTtl(Duration.ofDays(1))
                // 设置键序列化方式
                .serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(RedisSerializer.string()))
                // 设置值序列化方式
                .serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(RedisSerializer.json()))
                // 不处理空数据
                .disableCachingNullValues();
        CacheProperties.Redis redisProperties = cacheProperties.getRedis();
        // 设置cache前缀
        if (redisProperties.getKeyPrefix() != null) {
            config = config.prefixCacheNameWith(redisProperties.getKeyPrefix());
        }
        RedisCacheManager.RedisCacheManagerBuilder builder = RedisCacheManager.builder(redisConnectionFactory)
                .cacheDefaults(config);
        return builder.build();
    }
}

1. 本配置类，针对redis的序列化，关于key的序列化为String的默认序列化方式，关于value的序列化为json序列化方式，借助到了 GenericJackson2JsonRedisSerializer 类

2. 针对redisTemplate实例，RedisAutoConfiguration类中已经帮我们注入了 RedisTemplate<Object, Object> 和 RedisTemplate<String, String> 其中关于object的默认序列化方式为 jdk序列，性能相对较差且jdk序列化扩展性也不强，所以自定义RedisTemplate<String, Object>序列化方式，关于object采用json序列化

3. 关于RedisCacheManager 的配置办法，大家也可以参考RedisCacheConfiguration 配置类，很多配置的写法我们要学会参考源码的配置办法

4. RedisCacheManager负责生成和管理redisCache，从配置类中可以看到，RedisCacheManager其实是和redisTemplate公用一套redis连接的，redisCache本质上也是redis，但和redisTemplate的适用面又不太相同，个人理解redisCache主要与org.springframework.cache.annotation 包下的类如 @Cacheable 等注解结合使用，下面会有测试示例

测试Case

@RestController
public class RedisController {

    @Autowired
    private StringRedisTemplate stringRedisTemplate;

    @Autowired
    private RedisCacheManager redisCacheManager;

    @Autowired
    private CacheService cacheService;

    @Autowired
    private RedisTemplate<String, Object> redisTemplate;

    @GetMapping("/redis/put")
    public String put(String key, String value) {
        stringRedisTemplate.opsForValue().set(key, value);
        return "success!";
    }

    @GetMapping("/redis/putObj")
    public String putObj(String key) {
        redisTemplate.opsForValue().set(key, TestEntity.returnTestObj());
        return "success";
    }

    @GetMapping("/redis/getObj")
    public String getObj(String key) {
        Object o = redisTemplate.opsForValue().get(key);
        return JSON.toJSONString(o);
    }

    @GetMapping("/cache/put")
    public String cachePut(String key) {
        Cache testCache = redisCacheManager.getCache("testCache");
        testCache.put(key, TestEntity.returnTestObj());
        return "success!";
    }

    @GetMapping("/cache/get")
    public String cacheGet(String key) {
        TestEntity testEntity = cacheService.cacheGet(key);
        return JSON.toJSONString(testEntity);
    }

}


@Service
public class CacheService {

    /**
     * testCache为cacheName，会有具体的redisCache与其以Map结构来一一对应，不同redisCache均由redisCacheManager生成
     * @param key
     * @return
     */
    @Cacheable(value = "testCache", cacheManager = "redisCacheManager", key = "#key")
    public TestEntity cacheGet(String key) {
        return new TestEntity("缓存", "找不到");
    }
}

public class TestEntity implements Serializable {

    @Serial
    private static final long serialVersionUID = -4058390548264688398L;
    
    private String fieldOne;

    private String fieldTwo;

    private String enumField;

    private static String staticField = "yangqingwei";

    public TestEntity(String fieldOne, String fieldTwo) {
        this.fieldOne = fieldOne;
        this.fieldTwo = fieldTwo;
    }

    public TestEntity() {}
    
    public static TestEntity returnTestObj() {
        return new TestEntity("one", "two");
    }
}