0x01 问题
在kotlin中使用Spring Data Redis的时候如下配置无法解析对象。
@Bean
open fun playerTemplate(factory: ReactiveRedisConnectionFactory): ReactiveRedisTemplate<String, Player> {
val keySerializer = StringRedisSerializer()
val valueSerializer = Jackson2JsonRedisSerializer(Player::class.java)
val ctx = RedisSerializationContext.newSerializationContext<String, Player>()
.key(keySerializer).value(valueSerializer).hashKey(keySerializer).hashValue(valueSerializer).build()
return ReactiveRedisTemplate(factory, ctx)
}
0x02 解决方案
将配置修改如下
@Bean
open fun playerTemplate(factory: ReactiveRedisConnectionFactory): ReactiveRedisTemplate<String, Player> {
val keySerializer = StringRedisSerializer()
val valueSerializer = Jackson2JsonRedisSerializer(Player::class.java)
valueSerializer.setObjectMapper(ObjectMapper().registerModule(KotlinModule()))
val ctx = RedisSerializationContext.newSerializationContext<String, Player>()
.key(keySerializer).value(valueSerializer).hashKey(keySerializer).hashValue(valueSerializer).build()
return ReactiveRedisTemplate(factory, ctx)
}
<dependency>
<groupId>com.fasterxml.jackson.module</groupId>
<artifactId>jackson-module-kotlin</artifactId>
</dependency>
解决方案就是设置valueSerializer中的objectMapper为注册过KotlinModule的ObjectMapper。
0x03 Module
Module是jaskson databind为了支持新的数据类型增加的接口，将Module注册到ObjectMapper可以实现修改ObjectMapper默认的序列化和反序列化的行。上面就用到了jackson-module-kotlin提供的KotlinModule。