如何检测/建议Spring Data（JPA）存储库？

Question

我无法为spring数据jpa存储库提供建议。目的是void在特定存储库中使用自定义注释（在此示例中为ResourceNotFound）进行注释的（非常规）所有非公共方法，并在返回值为null或者为空集合时引发异常。

@Repository 
@ResourceNotFound
@Transactional(readOnly = true)
public interface CityRepository extends JpaRepository<City, Long>, JpaSpecificationExecutor<City> { … }

以下建议是将用注释的接口实现的所有公共方法进行连接@ResourceNotFound。

@Pointcut("within(com.digitalmisfits.spring.aop.annotation.ResourceNotFound *)")
public void beanAnnotatedWithResourceNotFound() {}

@Pointcut("execution(public * *(..))")
public void publicMethod() {}

@Around("beanAnnotatedWithResourceNotFound() && publicMethod()")
public Object publicMethodInsideAClassMarkedWithResourceNotFound(ProceedingJoinPoint pjp) throws Throwable {

    System.out.println("publicMethodInsideAClassMarkedWithResourceNotFound " + pjp.getTarget().toString());;

    Object retVal =  pjp.proceed();

    if(((MethodSignature) pjp.getSignature()).getReturnType() != Void.TYPE && isObjectEmpty(retVal))
        throw new RuntimeException("isObjectEmpty == true");

    return retVal;
}

该publicMethodInsideAClassMarkedWithResourceNotFound(…)方法的工作原理，当切入点isspecified为：

@Pointcut("execution(public * package.CityRepository+.*(..))")

但是，@ResourceNotFound未拾取注释。这可能是由于存储库接口的基础类是一个（代理的）SimpleJpaRepository不具有特定注释的事实。

有没有办法传播@ResourceNotFound到实现？

-更新-

更改了问题以反映以下事实：建议（仅）应仅适用于具有自定义注释的存储库。

Answer 1

尽管OP严重依赖于AspectJ解决方案，但目前的问题并不直接表明解决方案应限于AspectJ。因此，我想提供一种非AspectJ的方式来建议Spring
Data JPA存储库。它基于将自定义添加Interceptor到准系统Spring AOP代理拦截器链中。

首先，配置您的自定义RepositoryFactoryBean，例如

@Configuration
@EnableJpaRepositories(repositoryFactoryBeanClass = CustomRepositoryFactoryBean.class)
public class ConfigJpaRepositories {
}

接下来，实施CustomRepositoryFactoryBean添加自己RepositoryProxyPostProcessor的JpaRepositoryFactory

class CustomRepositoryFactoryBean<R extends JpaRepository<T, I>, T , I extends Serializable> extends JpaRepositoryFactoryBean<R, T, I> {

  protected RepositoryFactorySupport createRepositoryFactory(EntityManager em) {
    RepositoryFactorySupport factory = super.createRepositoryFactory(em);
    factory.addRepositoryProxyPostProcessor(new ResourceNotFoundProxyPostProcessor());
    return factory;
  }

}

您的RepositoryProxyPostProcessor实现应将您添加MethodInterceptor到ProxyFactory特定存储库（检查RepositoryInformation）：

class ResourceNotFoundProxyPostProcessor implements RepositoryProxyPostProcessor {

    @Override
    public void postProcess(ProxyFactory factory, RepositoryInformation repositoryInformation) {
        if (repositoryInformation.getRepositoryInterface().equals(CityRepository.class))
            factory.addAdvice(new ResourceNotFoundMethodInterceptor());
    }

}

并且在您MethodInterceptor（BTW是的子接口org.aopalliance.aop.Advice，所以仍然是一个建议:)）中，您具有AspectJ
@Around建议的全部功能：

class ResourceNotFoundMethodInterceptor implements MethodInterceptor {

    @Override
    public Object invoke(MethodInvocation invocation) throws Throwable {
        Method method = invocation.getMethod();
        ResourceNotFound resourceNotFound = method.getAnnotation(ResourceNotFound.class);
        //...
        Object result = invocation.proceed();
        //...
        return result;
    }
}