Spring Data JPA如何支持查询主键的子集？或者我是否需要为此实现自定义存储库方法？
有这样的课程：
@lombok.Data
@lombok.NoArgsConstructor
@lombok.AllArgsConstructor
@Entity
@Table(name = "my_entity")
class MyEntity {
@EmbeddedId
private Pk id;
public Pk getId() {
return id;
}
public void setId(Pk id) {
this.id = id;
}
}
@lombok.Data
@lombok.NoArgsConstructor
@lombok.AllArgsConstructor
@Embeddable
class Pk implements Serializable {
private Integer type;
private String userId;
}
interface MyEntityRepository extends org.springframework.data.jpa.repository.JpaRepository<MyEntity, Pk> {
java.util.Set<MyEntity> findAllByUserId(String userId);
}
在启动我的Spring Boot应用程序时，我收到错误：
Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'myEntityRepository': Invocation of init method failed; nested exception is org.springframework.data.mapping.PropertyReferenceException: No property user found for type MyEntity!
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1512)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:521)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:296)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:293)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:615)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479)
at org.springframework.context.annotation.AnnotationConfigApplicationContext.<init>(AnnotationConfigApplicationContext.java:73)
at com.myproject.backend.common.ServiceContext.start(ServiceContext.java:293)
at com.myproject.run(AbstractServiceContainer.java:55)
at com.myproject..run(AbstractServiceContainer.java:1)
at io.dropwizard.cli.EnvironmentCommand.run(EnvironmentCommand.java:42)
at io.dropwizard.cli.ConfiguredCommand.run(ConfiguredCommand.java:76)
at io.dropwizard.cli.Cli.run(Cli.java:70)
at io.dropwizard.Application.run(Application.java:72)
at com.myproject..main(CombinedServiceContainer.java:106)
Caused by: org.springframework.data.mapping.PropertyReferenceException: No property user found for type MyEntity!
at org.springframework.data.mapping.PropertyPath.<init>(PropertyPath.java:75)
at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:327)
at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:359)
at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:307)
at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:270)
at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:241)
at org.springframework.data.repository.query.parser.Part.<init>(Part.java:76)
at org.springframework.data.repository.query.parser.PartTree$OrPart.<init>(PartTree.java:213)
at org.springframework.data.repository.query.parser.PartTree$Predicate.buildTree(PartTree.java:321)
at org.springframework.data.repository.query.parser.PartTree$Predicate.<init>(PartTree.java:301)
at org.springframework.data.repository.query.parser.PartTree.<init>(PartTree.java:85)
at org.springframework.data.jpa.repository.query.PartTreeJpaQuery.<init>(PartTreeJpaQuery.java:60)
at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$CreateQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:91)
at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$CreateIfNotFoundQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:168)
at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$AbstractQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:69)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.<init>(RepositoryFactorySupport.java:320)
at org.springframework.data.repository.core.support.RepositoryFactorySupport.getRepository(RepositoryFactorySupport.java:169)
at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.initAndReturn(RepositoryFactoryBeanSupport.java:224)
at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.afterPropertiesSet(RepositoryFactoryBeanSupport.java:210)
at org.springframework.data.jpa.repository.support.JpaRepositoryFactoryBean.afterPropertiesSet(JpaRepositoryFactoryBean.java:92)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1571)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1509)
... 18 more
这与问题here类似，应该在那里得到解答，除了OP决定通过使用IdClass进入解决方案的另一条路线。虽然该解决方案有效但这个问题是为了表明没有做IdClass的支持方式。
This answer显示如何使用“按示例查询”执行此操作，这对于复合键的多个部分非常有用。
此问题与链接的答案不同，因为链接的答案显示如何通过编写查询方法名称来解决问题。这个问题询问如何通过在查询注释中编写SQL或HQL字符串来解决问题。
答案 0 :(得分：1)
只需自己定义查询：
@Query("select me from MyEntity me where me.id.userId = ?1")
java.util.Set<MyEntity> findAllByUserId(String userId);