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:
- Caused by: java.lang.IllegalArgumentException: DefaultSerializer requires a Serializable payload but received an object of type [com.entity.UserEntity]
- at org.springframework.core.serializer.DefaultSerializer.serialize(DefaultSerializer.java:43)
- at org.springframework.core.serializer.Serializer.serializeToByteArray(Serializer.java:56)
- at org.springframework.core.serializer.support.SerializingConverter.convert(SerializingConverter.java:60)
- ... 54 more
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
- @NoArgsConstructor
- public class UserEntity {
- /**
- * 用户名
- */
- private String username;
- /**
- * 年龄
- */
- private Integer age;
- /**
- * 所属部门
- */
- private Department department;
- /**
- * 创建时间
- */
- private Date createTime;
- /**
- * 手机号码
- */
- private List<String> phoneNumber;
- /**
- * 爱好
- */
- private Map<String, Object> hobby;
- }
部门类
- @Data
- @Builder
- @NoArgsConstructor
- @AllArgsConstructor
- public class Department {
- /**
- * 部门id
- */
- private String depId;
- /**
- * 部门名称
- */
- private String depName;
- /**
- * 父级部门
- */
- private String parentId;
- }
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 = new ArrayList<>();
- phoneNumbers.add("13016541724");
- phoneNumbers.add("18826173452");
- Map<String, Object> hobbys = new HashMap<>();
- hobbys.put("运行", "打羽毛球");
- hobbys.put("电影", "看电影");
- UserEntity userEntity = UserEntity.builder().username("张三").age(18).department(
- Department.builder().depId("djinefn213445nkqk").depName("研发中心").parentId("ncdjkn3j4njndcinw").build()
- ).createTime(new Date()).phoneNumber(phoneNumbers).hobby(hobbys)
- .build();
- ObjectHashMapper objectHashMapper = new ObjectHashMapper();
- 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");
- UserEntity userEntityRes = (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 = new ArrayList<>();
- phoneNumbers.add("13016541724");
- phoneNumbers.add("18826173452");
- Map<String, Object> hobbys = new HashMap<>();
- hobbys.put("运行", "打羽毛球");
- hobbys.put("电影", "看电影");
- UserEntity userEntity = UserEntity.builder().username("张三").age(18).department(
- Department.builder().depId("djinefn213445nkqk").depName("研发中心").parentId("ncdjkn3j4njndcinw").build()
- ).createTime(new Date()).phoneNumber(phoneNumbers).hobby(hobbys)
- .build();
- Jackson2HashMapper jackson2HashMapper = new Jackson2HashMapper(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");
- UserEntity userEntityRes = (UserEntity) jackson2HashMapper.fromHash(map1);
BeanUtilsHashMapper
BeanUtilsHashMapper
使用Spring的BeanUtils。
- List<String> phoneNumbers = new ArrayList<>();
- phoneNumbers.add("13016541724");
- phoneNumbers.add("18826173452");
- Map<String, Object> hobbys = new HashMap<>();
- hobbys.put("运行", "打羽毛球");
- hobbys.put("电影", "看电影");
- UserEntity userEntity = UserEntity.builder().username("张三").age(18).department(
- Department.builder().depId("djinefn213445nkqk").depName("研发中心").parentId("ncdjkn3j4njndcinw").build()
- ).createTime(new Date()).phoneNumber(phoneNumbers).hobby(hobbys)
- .build();
- BeanUtilsHashMapper beanUtilsHashMapper = new BeanUtilsHashMapper(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");
- UserEntity userEntityRes = (UserEntity) beanUtilsHashMapper.fromHash(map1);
运行会报
- Caused by: org.apache.commons.beanutils.ConversionException: Can't convert value '' to type interface java.util.List
- at org.apache.commons.beanutils.converters.AbstractConverter.conversionException(AbstractConverter.java:474)
- at org.apache.commons.beanutils.converters.StringConverter.convertToType(StringConverter.java:96)
- at org.apache.commons.beanutils.converters.AbstractConverter.handleMissing(AbstractConverter.java:312)
- ... 58 more
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
- Caused by: org.apache.commons.beanutils.ConversionException: Can't convert value '' to type class java.util.ArrayList
- at org.apache.commons.beanutils.converters.AbstractConverter.conversionException(AbstractConverter.java:474)
- at org.apache.commons.beanutils.converters.StringConverter.convertToType(StringConverter.java:96)
- at org.apache.commons.beanutils.converters.AbstractConverter.handleMissing(AbstractConverter.java:312)
- ... 58 more
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。
以上就是将没有实现Serializable的类存储到Redis中方法示例的详细内容,更多关于Redis存储Serializable类的资料请关注w3xue其它相关文章!