java - 如何编写 Spring Data 方法名称来检索列中的所有元素？

Question

假设我有类(class):

@Entity
public class Bean {
    @Id
    private String beanId;
    //other fields & setters and getters
}

以及相应的 Spring Data JPA 存储库，我希望在 List<String> 中拥有该存储库所有beanIds .

@RepositoryDefinition(domainClass = Bean.class, idClass = String.class)
public interface BeanRepository {
    @Query("select b.beanId from Bean b")
    List<String> findAllBeanId();
}

如上所述，一切都按预期工作；但这是一个简单的操作，我不想明确地编写查询。该方法的名称应该是什么，以便 Spring Data 可以解析它并获得上述查询(或相同的功能)。我在引用文档中搜索了两本关于 Spring Data 的书。以上名称 ( findAllBeanId ) 和我尝试过的其他名称 ( findBeanId 、 findBeanBeanId 等) 抛出以下异常作为根本原因:

org.springframework.data.mapping.PropertyReferenceException: No property find found for type Trade
    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:353)
    at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:353)
    at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:307)
    at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:271)
    at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:245)
    at org.springframework.data.repository.query.parser.Part.<init>(Part.java:72)
    at org.springframework.data.repository.query.parser.PartTree$OrPart.<init>(PartTree.java:180)
    at org.springframework.data.repository.query.parser.PartTree$Predicate.buildTree(PartTree.java:260)
    at org.springframework.data.repository.query.parser.PartTree$Predicate.<init>(PartTree.java:240)
    at org.springframework.data.repository.query.parser.PartTree.<init>(PartTree.java:68)
    at org.springframework.data.jpa.repository.query.PartTreeJpaQuery.<init>(PartTreeJpaQuery.java:57)
    at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$CreateQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:90)
    at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$CreateIfNotFoundQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:162)
    at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$AbstractQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:68)
    at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.<init>(RepositoryFactorySupport.java:279)
    at org.springframework.data.repository.core.support.RepositoryFactorySupport.getRepository(RepositoryFactorySupport.java:147)
    at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.getObject(RepositoryFactoryBeanSupport.java:153)
    at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.getObject(RepositoryFactoryBeanSupport.java:43)
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:142)
    ... 22 more

Answer 1

在 Spring 文档中:http://static.springsource.org/spring-data/jpa/docs/1.3.0.RELEASE/reference/html/jpa.repositories.html通过从方法名称生成的查询仅从实体获取特定列/属性没有任何意义。所以我认为目前是不可能的。