Redis的序列化配置

一 源码概述

public class RedisTemplate<K, V> extends RedisAccessor implements RedisOperations<K, V>, BeanClassLoaderAware {
    private boolean enableTransactionSupport = false;
    private boolean exposeConnection = false;
    private boolean initialized = false;
    private boolean enableDefaultSerializer = true;
    @Nullable
    private RedisSerializer<?> defaultSerializer;
    @Nullable
    private ClassLoader classLoader;
    @Nullable
    private RedisSerializer keySerializer = null;
    @Nullable
    private RedisSerializer valueSerializer = null;
    @Nullable
    private RedisSerializer hashKeySerializer = null;
    @Nullable
    private RedisSerializer hashValueSerializer = null;
    private RedisSerializer<String> stringSerializer = RedisSerializer.string();
    @Nullable
    private ScriptExecutor<K> scriptExecutor;
    private final ValueOperations<K, V> valueOps = new DefaultValueOperations(this);
    private final ListOperations<K, V> listOps = new DefaultListOperations(this);
    private final SetOperations<K, V> setOps = new DefaultSetOperations(this);
    private final StreamOperations<K, ?, ?> streamOps = new DefaultStreamOperations(this, new ObjectHashMapper());
    private final ZSetOperations<K, V> zSetOps = new DefaultZSetOperations(this);
    private final GeoOperations<K, V> geoOps = new DefaultGeoOperations(this);
    private final HyperLogLogOperations<K, V> hllOps = new DefaultHyperLogLogOperations(this);
    private final ClusterOperations<K, V> clusterOps = new DefaultClusterOperations(this);

    public RedisTemplate() {
    }

    public void afterPropertiesSet() {
        super.afterPropertiesSet();
        boolean defaultUsed = false;
        if (this.defaultSerializer == null) {
            this.defaultSerializer = new JdkSerializationRedisSerializer(this.classLoader != null ? this.classLoader : this.getClass().getClassLoader());
        }

        if (this.enableDefaultSerializer) {
            if (this.keySerializer == null) {
                this.keySerializer = this.defaultSerializer;
                defaultUsed = true;
            }

            if (this.valueSerializer == null) {
                this.valueSerializer = this.defaultSerializer;
                defaultUsed = true;
            }

            if (this.hashKeySerializer == null) {
                this.hashKeySerializer = this.defaultSerializer;
                defaultUsed = true;
            }

            if (this.hashValueSerializer == null) {
                this.hashValueSerializer = this.defaultSerializer;
                defaultUsed = true;
            }
        }

        if (this.enableDefaultSerializer && defaultUsed) {
            Assert.notNull(this.defaultSerializer, "default serializer null and not all serializers initialized");
        }

        if (this.scriptExecutor == null) {
            this.scriptExecutor = new DefaultScriptExecutor(this);
        }

        this.initialized = true;
    }
}

根据源码可知，当没有配置序列化策略的时候，采用的是默认的序列化策略，即

this.defaultSerializer = new JdkSerializationRedisSerializer(this.classLoader != null ? this.classLoader : this.getClass().getClassLoader());

默认的序列化方式使得我们在Redis客户端查看是不是很好查看。

二 自定义序列化策略

        key采用字符串系列化策略，而value则采用fastJson序列化策略。

        自定义FastJson序列化配置

public class FastJsonRedisSerializer<T> implements RedisSerializer<T> {
    private static final Charset DEFAULT_CHARSET = Charset.forName("UTF-8");
    private Class<T> clazz;
    public FastJsonRedisSerializer(Class<T> clazz) {
        super();
        this.clazz = clazz;
    }

    @Override
    public byte[] serialize(T t) throws SerializationException {
        if (null == t) {
            return new byte[0];
        }
        return JSON.toJSONString(t, SerializerFeature.WriteClassName).getBytes(DEFAULT_CHARSET);
    }

    @Override
    public T deserialize(byte[] bytes) throws SerializationException {
        if (null == bytes || bytes.length <= 0) {
            return null;
        }
        String str = new String(bytes, DEFAULT_CHARSET);
        //禁用关键字检测
        return JSON.parseObject(str, clazz, Feature.DisableSpecialKeyDetect);
    }
}

         redis序列化配置

@Configuration
@AutoConfigureAfter(RedisAutoConfiguration.class)
public class RedisCacheAutoConfiguration {

    @Bean
    @ConditionalOnMissingBean(name = "redisTemplate")
    public RedisTemplate<Object, Object> redisTemplate(
            RedisConnectionFactory redisConnectionFactory) {
        RedisTemplate<Object, Object> template = new RedisTemplate<>();
        //使用fastjson序列化
        FastJsonRedisSerializer fastJsonRedisSerializer = new FastJsonRedisSerializer(Object.class);
        // value值的序列化采用fastJsonRedisSerializer
        template.setValueSerializer(fastJsonRedisSerializer);
        template.setHashValueSerializer(fastJsonRedisSerializer);
        // key的序列化采用StringRedisSerializer
        template.setKeySerializer(new StringRedisSerializer());
        template.setHashKeySerializer(new StringRedisSerializer());
        template.setConnectionFactory(redisConnectionFactory);
        return template;
    }

    @Bean
    @ConditionalOnMissingBean(StringRedisTemplate.class)
    public StringRedisTemplate stringRedisTemplate(
            RedisConnectionFactory redisConnectionFactory) {
        StringRedisTemplate template = new StringRedisTemplate();
        template.setConnectionFactory(redisConnectionFactory);
        return template;
    }

}

序列化配置之后，key和value分别是String和json格式，易于查看：