如何将没有实现Serializable的类存储到Redis中(redis,serializable,开发技术)

将实例对象存储到Redis中报错

你有没有遇到过这种情况，需要将实例对象存储到Redis中，但是类的字段包含第三方依赖中的类并且此类没有 implements Serializable。 执行时就会报没有序列化的错：

Causedby:java.lang.IllegalArgumentException:DefaultSerializerrequiresaSerializablepayloadbutreceivedanobjectoftype[com.entity.UserEntity] atorg.springframework.core.serializer.DefaultSerializer.serialize(DefaultSerializer.java:43) atorg.springframework.core.serializer.Serializer.serializeToByteArray(Serializer.java:56) atorg.springframework.core.serializer.support.SerializingConverter.convert(SerializingConverter.java:60) ...54more

有三种方法如下

ObjectHashMapper

ObjectHashMapper使用对象到哈希映射。

需存redis的类如下：

用户类

@Data@Builder@AllArgsConstructor@NoArgsConstructorpublicclassUserEntity{/***用户名*/privateStringusername;/***年龄*/privateIntegerage;/***所属部门*/privateDepartmentdepartment;/***创建时间*/privateDatecreateTime;/***手机号码*/privateList<String>phoneNumber;/***爱好*/privateMap<String,Object>hobby;}

部门类

@Data@Builder@NoArgsConstructor@AllArgsConstructorpublicclassDepartment{/***部门id*/privateStringdepId;/***部门名称*/privateStringdepName;/***父级部门*/privateStringparentId;}

注意：上面两个类都没有实现序列化

通过ObjectHashMapper的toHash和fromHash实现

List<String>phoneNumbers=newArrayList<>();phoneNumbers.add("13016541724");phoneNumbers.add("18826173452");Map<String,Object>hobbys=newHashMap<>();hobbys.put("运行","打羽毛球");hobbys.put("电影","看电影");UserEntityuserEntity=UserEntity.builder().username("张三").age(18).department(Department.builder().depId("djinefn213445nkqk").depName("研发中心").parentId("ncdjkn3j4njndcinw").build()).createTime(newDate()).phoneNumber(phoneNumbers).hobby(hobbys).build();ObjectHashMapperobjectHashMapper=newObjectHashMapper();Map<byte[],byte[]>map=objectHashMapper.toHash(userEntity);redisTemplate.opsForHash().put("TEST_OBJECT","a",map);Map<byte[],byte[]>map1=(Map<byte[],byte[]>)redisTemplate.opsForHash().get("TEST_OBJECT","a");UserEntityuserEntityRes=(UserEntity)objectHashMapper.fromHash(map1);

Jackson2HashMapper

Jackson2HashMapper通过使用FasterXMLJackson为域对象提供Redis哈希映射。可以将顶级属性映射为哈希字段名，也可以选择展平结构。简单类型映射到简单值。复杂类型（嵌套对象、集合、映射等）表示为嵌套JSON。Jackson2HashMapper平展为所有嵌套属性创建单独的哈希条目，并尽可能将复杂类型解析为简单类型。

List<String>phoneNumbers=newArrayList<>();phoneNumbers.add("13016541724");phoneNumbers.add("18826173452");Map<String,Object>hobbys=newHashMap<>();hobbys.put("运行","打羽毛球");hobbys.put("电影","看电影");UserEntityuserEntity=UserEntity.builder().username("张三").age(18).department(Department.builder().depId("djinefn213445nkqk").depName("研发中心").parentId("ncdjkn3j4njndcinw").build()).createTime(newDate()).phoneNumber(phoneNumbers).hobby(hobbys).build();Jackson2HashMapperjackson2HashMapper=newJackson2HashMapper(true);Map<String,Object>map=jackson2HashMapper.toHash(userEntity);redisTemplate.opsForHash().put("TEST_OBJECT","a",map);Map<String,Object>map1=(Map<String,Object>)redisTemplate.opsForHash().get("TEST_OBJECT","a");UserEntityuserEntityRes=(UserEntity)jackson2HashMapper.fromHash(map1);

BeanUtilsHashMapper

BeanUtilsHashMapper使用Spring的BeanUtils。

List<String>phoneNumbers=newArrayList<>();phoneNumbers.add("13016541724");phoneNumbers.add("18826173452");Map<String,Object>hobbys=newHashMap<>();hobbys.put("运行","打羽毛球");hobbys.put("电影","看电影");UserEntityuserEntity=UserEntity.builder().username("张三").age(18).department(Department.builder().depId("djinefn213445nkqk").depName("研发中心").parentId("ncdjkn3j4njndcinw").build()).createTime(newDate()).phoneNumber(phoneNumbers).hobby(hobbys).build();BeanUtilsHashMapperbeanUtilsHashMapper=newBeanUtilsHashMapper(UserEntity.class);Map<String,Object>map=beanUtilsHashMapper.toHash(userEntity);redisTemplate.opsForHash().put("TEST_OBJECT","a",map);Map<String,Object>map1=(Map<String,Object>)redisTemplate.opsForHash().get("TEST_OBJECT","a");UserEntityuserEntityRes=(UserEntity)beanUtilsHashMapper.fromHash(map1);

运行会报

Causedby:org.apache.commons.beanutils.ConversionException:Can'tconvertvalue''totypeinterfacejava.util.List atorg.apache.commons.beanutils.converters.AbstractConverter.conversionException(AbstractConverter.java:474) atorg.apache.commons.beanutils.converters.StringConverter.convertToType(StringConverter.java:96) atorg.apache.commons.beanutils.converters.AbstractConverter.handleMissing(AbstractConverter.java:312) ...58more

从报错中可以看出，List为interface，无法转换。将List改为ArrayList,Map改为HashMap再执行报如下错误

Causedby:org.apache.commons.beanutils.ConversionException:Can'tconvertvalue''totypeclassjava.util.ArrayList atorg.apache.commons.beanutils.converters.AbstractConverter.conversionException(AbstractConverter.java:474) atorg.apache.commons.beanutils.converters.StringConverter.convertToType(StringConverter.java:96) atorg.apache.commons.beanutils.converters.AbstractConverter.handleMissing(AbstractConverter.java:312) ...58more

排查会发现，phoneNumber的两个手机号码toHash后变成了一个手机号码

这是BeanUtilsHashMapper的一个缺陷。