查询创建方法给出错误

Question

我的实体有一个类似

的字段

@Column(name = "workflow_status", columnDefinition = "nvarchar(255)")
private String workflow_status;

所以在我的 Controller 中我想通过 workflow_status 获取条目，我编写了 JPA 提供的 Query 方法

List<Programme> findByWorkflow_status(String workflow_status);

但这会出错

Caused by: java.lang.IllegalArgumentException: Failed to create query method public abstract java.util.List com.taap.backend.programmes.repositories.ProgRepo.findByWorkflow_status(java.lang.String)! No property workflow found for type Programme!
at org.springframework.data.jpa.repository.query.PartTreeJpaQuery.<init>(PartTreeJpaQuery.java:76) ~[spring-data-jpa-1.11.9.RELEASE.jar:na]
at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$CreateQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:101) ~[spring-data-jpa-1.11.9.RELEASE.jar:na]
at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$CreateIfNotFoundQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:207) ~[spring-data-jpa-1.11.9.RELEASE.jar:na]
at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$AbstractQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:77) ~[spring-data-jpa-1.11.9.RELEASE.jar:na]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.<init>(RepositoryFactorySupport.java:451) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.repository.core.support.RepositoryFactorySupport.getRepository(RepositoryFactorySupport.java:224) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.initAndReturn(RepositoryFactoryBeanSupport.java:277) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.afterPropertiesSet(RepositoryFactoryBeanSupport.java:263) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.jpa.repository.support.JpaRepositoryFactoryBean.afterPropertiesSet(JpaRepositoryFactoryBean.java:101) ~[spring-data-jpa-1.11.9.RELEASE.jar:na]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1687) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1624) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
... 48 common frames omitted
Caused by: org.springframework.data.mapping.PropertyReferenceException: No property workflow found for type Programme!
at org.springframework.data.mapping.PropertyPath.<init>(PropertyPath.java:77) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:329) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:309) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:272) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:243) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.repository.query.parser.Part.<init>(Part.java:76) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.repository.query.parser.PartTree$OrPart.<init>(PartTree.java:247) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.repository.query.parser.PartTree$Predicate.buildTree(PartTree.java:398) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.repository.query.parser.PartTree$Predicate.<init>(PartTree.java:378) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.repository.query.parser.PartTree.<init>(PartTree.java:89) ~[spring-data-commons-1.13.9.RELEASE.jar:na]
at org.springframework.data.jpa.repository.query.PartTreeJpaQuery.<init>(PartTreeJpaQuery.java:70) ~[spring-data-jpa-1.11.9.RELEASE.jar:na]
... 58 common frames omitted

非常感谢任何帮助！ :)

Answer 1

spring JPA 中的下划线(_) 字符具有保留含义。

• 或者，更改变量的名称，强烈建议这样做。

改变

private String workflow_status;

到

private String workflowStatus;

和

List<Programme> findByWorkflow_status(String workflow_status);

到

List<Programme> findByWorkflowStatus(String workflow_status);

• 或者，使用另一个下划线对字符进行转义。

类似这样的：

List<Programme> findByWorkflow__status(String workflow_status);

有关更多信息，请参阅文档here。