问题描叙

出现这种乱码前缀的原因是没有进行序列化，因此导致在传输过程出现乱码问题，存到数据库，发现 key,hash key/value 都有 \xAC\xED\x00\x05t\x00 前缀。RedisTemplate类中默认是没有设置序列化的。

解决方法

设置RedisTemplate的序列化方式

import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.context.annotation.Bean;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;public class RedisConfig {@Bean(name = "redisTemplate")//配置redisTemplate//默认情况下redisTemplate只能支持redisTemplate<String,String>//需要自定义 RedisTemplate,设置序列化public RedisTemplate<String,Object> redisTemplate(RedisConnectionFactory factory){RedisTemplate<String,Object> template = new RedisTemplate <>();template.setConnectionFactory(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);StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();// key采用String的序列化方式template.setKeySerializer(stringRedisSerializer);// hash的key也采用String的序列化方式template.setHashKeySerializer(stringRedisSerializer);// value序列化方式采用jacksontemplate.setValueSerializer(jackson2JsonRedisSerializer);// hash的value序列化方式采用jacksontemplate.setHashValueSerializer(jackson2JsonRedisSerializer);template.afterPropertiesSet();return template;}
}

注意：用了StringRedisSerializer之后，redis库的数据都是以String类型保存，所以int类型的整数，在保存时，会类型上升， 先变成double，然后再存成String，也就是1会存成"1.0"，所以如果保存int数据时，需要自己在代码中单独处理下。上面修改全局配置不能兼容新老数据，新增配置可以兼容。

修改序列化方式后，数据不兼容报错

org.springframework.data.redis.serializer.SerializationException: Cannot deserialize; nested exception is org.springframework.core.serializer.support.SerializationFailedException: Failed to deserialize payload. Is the byte array a result of corresponding serialization for DefaultDeserializer?; nested exception is java.io.StreamCorruptedException: invalid stream header: E5A487E6

使用多个redisTemplate配置

@Configuration
public class RedisConfig {@Bean@Primarypublic RedisTemplate redisTemplate(RedisConnectionFactory connectionFactory) {RedisTemplate redisTemplate = new RedisTemplate<>();redisTemplate.setConnectionFactory(connectionFactory);redisTemplate.setKeySerializer(new StringRedisSerializer());redisTemplate.setValueSerializer(new StringRedisSerializer());redisTemplate.setHashKeySerializer(new StringRedisSerializer());redisTemplate.setHashValueSerializer(new StringRedisSerializer());return redisTemplate;}@Bean(name = "ByteRedisTemplate")public RedisTemplate ByteRedisTemplate(RedisConnectionFactory redisConnectionFactory) {RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();redisTemplate.setConnectionFactory(redisConnectionFactory);redisTemplate.setKeySerializer(new StringRedisSerializer());redisTemplate.setValueSerializer(RedisSerializer.byteArray());redisTemplate.setHashKeySerializer(new StringRedisSerializer());redisTemplate.setHashValueSerializer(RedisSerializer.byteArray());return redisTemplate;}
}

使用方法 

@RestController
public class PublishDemo {@Autowiredprivate RedisTemplate redisTemplate;@Autowired@Qualifier("ByteRedisTemplate")private RedisTemplate byteRedisTemplate;@RequestMapping("set")public void set() {String key1 = "t1";String value = "12345";String key2 = "t2";String value2 = "54321";redisTemplate.opsForValue().set(key1, value);byteRedisTemplate.opsForValue().set(key2, value2.getBytes());}@RequestMapping("get")public void get() {Object t1 = redisTemplate.opsForValue().get("t1");System.out.println("t1:" + t1.toString());Object o = byteRedisTemplate.opsForValue().get("t2");System.out.println("t2:" + Arrays.toString((byte[]) o));}
}

对象存hash

entityMap.forEach((field, value) -> redisTemplate.opsForHash().put(String.format(REDIS_CONN_KEY, entity.getId()), field, value != null ? String.valueOf(value) : ""));