如何注释自定义Spring Boot自定义存储库? [英] How to annotate a custom Spring Boot custom repository?

问题描述

我有一个名为Screenshot的实体类和一个声明为这样的存储库:

I have an entity class called Screenshot and and a repository declared as this:

public interface ScreenshotRepository extends JpaRepository<Screenshot, UUID>, ScreenshotRepositoryCustom

自定义存储库的定义如下:

The custom repository is defined like this:

interface ScreenshotRepositoryCustom

和

class ScreenshotRepositoryImpl implements ScreenshotRepositoryCustom {
    private final ScreenshotRepository screenshotRepo;

    @Autowired
    public ScreenshotRepositoryImpl(ScreenshotRepository screenshotRepo) {
        this.screenshotRepo = screenshotRepo;
    }

这是在另一个堆栈溢出问题中描述的内容:如何向Spring Data JPA添加自定义方法

This is following what's described in this other Stack Overflow question: How to add custom method to Spring Data JPA

现在，IntelliJ给我一个警告:

Now, IntelliJ is giving me a warning:

Autowired members must be defined in a valid Spring bean

我尝试将这些注释添加到ScreenshotRepositoryImpl中，但没有起作用:

I tried adding these annotations to ScreenshotRepositoryImpl but none of the worked:

• @Repository
• @Component
• @Service

• @Repository
• @Component
• @Service

，但无济于事.显然有些是错误的，但我正在尝试.什么是正确的注释.

but none work. Obviously some are wrong but I was experimenting. What's the correct annotation.

使用@Repository时，出现此错误:

2017-11-23 12:30:04.064  WARN 20576 --- [  restartedMain] ationConfigEmbeddedWebApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'screenshotsController' defined in file [C:\Users\pupeno\Documents\Dashman\java\dashmanserver\out\production\classes\tech\dashman\server\controllers\ScreenshotsController.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'screenshotRepositoryImpl' defined in file [C:\Users\pupeno\Documents\Dashman\java\dashmanserver\out\production\classes\tech\dashman\server\models\ScreenshotRepositoryImpl.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.BeanCurrentlyInCreationException: Error creating bean with name 'screenshotRepositoryImpl': Requested bean is currently in creation: Is there an unresolvable circular reference?
2017-11-23 12:30:04.064  INFO 20576 --- [  restartedMain] j.LocalContainerEntityManagerFactoryBean : Closing JPA EntityManagerFactory for persistence unit 'default'
2017-11-23 12:30:04.064  INFO 20576 --- [  restartedMain] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2017-11-23 12:30:04.080  INFO 20576 --- [  restartedMain] utoConfigurationReportLoggingInitializer : 

Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
2017-11-23 12:30:04.080 ERROR 20576 --- [  restartedMain] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

The dependencies of some of the beans in the application context form a cycle:

   screenshotsController defined in file [C:\Users\pupeno\Documents\Dashman\java\dashmanserver\out\production\classes\tech\dashman\server\controllers\ScreenshotsController.class]
┌─────┐
|  screenshotRepositoryImpl defined in file [C:\Users\pupeno\Documents\Dashman\java\dashmanserver\out\production\classes\tech\dashman\server\models\ScreenshotRepositoryImpl.class]
└─────┘

推荐答案

发生了什么事?

您的依存关系形成一个循环:ScreenshotRepository扩展了ScreenshotRepositoryCustom，但是ScreenshotRepositoryCustom的实现依赖于ScreenshotRepository.由于这个周期，所有Bean都无法完成其实例化.

What is happening?

Your dependencies form a cycle: ScreenshotRepository extends ScreenshotRepositoryCustom, but the ScreenshotRepositoryCustom implementation depends on ScreenshotRepository. Because of this cycle, none of the beans can complete their instantiation.

在这些情况下，Spring Data不支持通过构造函数进行注入.尝试这样做将导致依赖周期错误.为了能够将ScreenshotRepository注入到ScreenShotRepositoryImpl中，您需要通过字段进行注入:

Spring Data does not support injection via constructor in these scenarios. Attempting to do so will result in a dependency cycle error. To be able to inject ScreenshotRepository into ScreenShotRepositoryImpl, you'd need to do injection via field:

@Repository
public class ScreenshotRepositoryImpl implements ScreenshotRepositoryCustom {

    @Autowired
    ScreenshotRepository screenshotRepository ;

    ...

}

这篇关于如何注释自定义Spring Boot自定义存储库?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！