尝试使用Spring Data JPA创建自定义存储库时，找不到类型错误的属性 [英] No property found for type error when try to create custom repository with Spring Data JPA

问题描述

我有一个Media实体，它有一些用户上传文件的基本字段。为了保存上传文件的字节，我想创建一个包含该功能的自定义存储库。按照 Spring文档，我创建了一个如下所示的界面：

I have a Media entity that has some basic fields for files uploaded by the user. For saving the bytes of the files uploaded, I want to create a custom repository that holds that functionality. Following the steps in the Spring documentation, I've created an interface that looks like this:

public interface MediaBytesRepository
{
    public byte[] getBytes(Media media) throws IOException;
    public void saveBytes(Media media, byte[] bytes) throws IOException;
    public void appendBytes(Media media, byte[] bytes) throws IOException;
    public void deleteBytes(Media media) throws IOException;
    public boolean bytesExist(Media media) throws IOException;
}

然后我提供了一个名为 MediaBytesRepositoryImpl的接口实现

Then I provided an implementation for this interface called MediaBytesRepositoryImpl

有了这个，我创建了以下界面：

With this, I then created the following interface:

public interface MediaRepository extends JpaRepository<Media, Long>, MediaBytesRepository
{
}

现在，当我启动服务器时，我得到以下堆栈跟踪：

Now, when I start up the server, I get the following stack trace:

SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mediaRepository': FactoryBean threw exception on object creation; nested exception is java.lang.IllegalArgumentException: Could not create query metamodel for method public abstract void com.foo.bar.core.media.MediaBytesRepository.saveBytes(com.foo.bar.core.media.Media,byte[]) throws java.io.IOException!
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:149)
.....
Caused by: java.lang.IllegalArgumentException: Could not create query metamodel for method public abstract void com.foo.bar.core.media.MediaBytesRepository.saveBytes(com.foo.bar.core.media.Media,byte[]) throws java.io.IOException!
    at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$CreateQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:92)
    at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$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:280)
    at org.springframework.data.repository.core.support.RepositoryFactorySupport.getRepository(RepositoryFactorySupport.java:148)
    at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.getObject(RepositoryFactoryBeanSupport.java:125)
    at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.getObject(RepositoryFactoryBeanSupport.java:41)
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:142)
    ... 20 more
 Caused by: java.lang.IllegalArgumentException: No property save found for type class com.foo.bar.core.media.Media
    at org.springframework.data.mapping.PropertyPath.<init>(PropertyPath.java:73)
    at org.springframework.data.mapping.PropertyPath.<init>(PropertyPath.java:92)
    at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:319)
    at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:333)
    at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:301)
    at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:265)
    at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:239)
    at org.springframework.data.repository.query.parser.Part.<init>(Part.java:70)
    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)
    ... 27 more

我发现这个类似的帖子，但那里的建议（所有在同一个包中，命名为conv我正在做的事情。我的所有媒体类和接口都在同一个包中，我使用的是Impl后缀。

I found this similar post, but the suggestions there (all in same package, naming convention) are things I'm already doing. All my media classes and interfaces are in the same package, and I'm using the "Impl" suffix.

有人可以说明我为什么会这样做这个错误以及我如何解决它？谢谢。

Can someone please shed some light on why I'm getting this error and how I can fix it? Thanks.

推荐答案

您写道：

<那里的建议（所有在同一个包中，命名约定）都是我已经在做的事情。

the suggestions there (all in same package, naming convention) are things I'm already doing.

不，你没有。

将 MediaBytesRepository 重命名为 MediaRepositoryCustom 。

当然，您需要实现 MediaRepositoryCustom ，名称为 MediaRepositoryImpl 。

And of course you need an implementation of MediaRepositoryCustom with the name MediaRepositoryImpl.

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