在 Hibernate 中使用 Spring boot 配置的 Jackson Objectmapper

如何解决在 Hibernate 中使用 Spring boot 配置的 Jackson Objectmapper

我想将 Hibernate 配置为使用 Spring 创建的 Jackson 的 Objectmapper 在 json 和实体之间进行映射。在我正在处理的项目中，我已经将 Jooq 配置为使用 Spring 的 ObjectMapper，但是我在如何配置 Hibernate 以使用它时遇到了麻烦。 目标最终是让 Jooq 和 Hibernate 使用相同的 ObjectMapper。

我检查了弗拉德的这个article。不幸的是，文章中给出的所有技巧都不适用于我正在从事的项目。

这是我尝试过的示例配置

@Configuration
public class HibernateConfiguration implements HibernatePropertiesCustomizer {
    //Autowire Objectmapper created by Spring
    @Autowired
    ObjectMapper objectMapper;

    @Override
    public void customize(Map<String,Object> hibernateProperties) {
        ObjectMappersupplier objectMappersupplier = () -> objectMapper;
        // Below config doesn't work since Hibernate types creates it's own mapper
        hibernateProperties.put("hibernate.types.jackson.object.mapper",objectMappersupplier);
}

也尝试了相同的方法，将 Objectmapper 添加到 hibernate-types.properties。

#Used by Hibernate but cannot get reference of Spring managed ObjectMapper since this is class is called outside of Spring's context.
hibernate.types.jackson.object.mapper=path.to.ObjectMappersupplier

我使用的另一种方法，但在从 JSON 转换为 NullpointerException 类中的实体时失败并显示 JsonTypeDescriptor。

@Configuration
public class HibernateConfiguration implements HibernatePropertiesCustomizer{

    @Autowired
    ObjectMapper objectMapper;

    @Override
    public void customize(Map<String,Object> hibernateProperties) {
        // Underlying implementation needs some JavaType or propertyClass,otherwise when converting 
        // from JSON we get a nullpointer.
        var jsonBinaryType = new JsonBinaryType(objectMapper);
        hibernateProperties.put("hibernate.type_contributors",(TypeContributorList) () -> 
        Collections.singletonList((typeContributions,serviceRegistry) -> 
                      typeContributions.contributeType(jsonBinaryType)));
}

以下是实体超类的类型声明。

// This makes Hibernate types create it's own mapper.
@TypeDef(name = "jsonb",typeClass = JsonBinaryType.class)
@MappedSuperclass
public abstract class Entity{

}

那么，是否有任何可能的解决方案可以将 Spring 管理的 ObjectMapper 连接到 Hibernate？

解决方法

我终于想通了，但这是一个创造性的解决方案......

TLDR：我有一个 bean，它将 Spring 配置的 objectMapper 存储在静态字段中。 BeanFactoryPostProcessor 确保在 Hibernate（类型）尝试加载/获取 ObjectMapper 之前初始化此 bean。

hibernate.properties

hibernate.types.jackson.object.mapper=com.github.lion7.example.HibernateObjectMapperSupplier

HibernateObjectMapperSupplier.kt

package com.github.lion7.example

import com.fasterxml.jackson.databind.ObjectMapper
import com.vladmihalcea.hibernate.type.util.ObjectMapperSupplier
import org.springframework.beans.factory.config.BeanFactoryPostProcessor
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory
import org.springframework.stereotype.Component

class HibernateObjectMapperSupplier : ObjectMapperSupplier {
    override fun get(): ObjectMapper =
        ObjectMapperHolder.objectMapper
}

@Component
class ObjectMapperHolder(objectMapper: ObjectMapper) {

    companion object {
        lateinit var objectMapper: ObjectMapper
    }

    init {
        Companion.objectMapper = objectMapper
    }

}

@Component
class ObjectMapperDependencyFixer : BeanFactoryPostProcessor {
    override fun postProcessBeanFactory(beanFactory: ConfigurableListableBeanFactory) {
        val beanDefinition = beanFactory.getBeanDefinition("entityManagerFactory")
        val oldDependsOn = beanDefinition.dependsOn ?: emptyArray()
        val newDependsOn = oldDependsOn + "objectMapperHolder"
        beanDefinition.setDependsOn(*newDependsOn)
    }
}

与要点相同的代码：https://gist.github.com/lion7/c8006b69a309e38183deb69124b888b5