“不满意的依存关系”； -具有相同接口的不同无状态Bean [英] "Unsatisfied Dependencies" - Different Stateless Beans with same Interface

问题描述

我有三个 @Stateless Bean，它们具有相同的接口。

I have three @Stateless Beans with the same interface.

public interface ReportService
{
    List<String> determineRelevantData();

    Report generate(ReportRequest request, Locale locale) throws ServiceFailedException;
}

我将这些bean注入一个外观bean：

I inject the beans in one facade bean:

@Stateless
public class ReportServiceFacadeBean implements ReportServiceFacadeLocal
{
    @Inject
    private FirstReportBean firstReport;

    @Inject
    private SecondReportBean secondReport;

    @Inject
    private ThirdReportBean thirdReport;

    [...]
}

我部署时这样，我得到：

When I deploy it this way, I get:

WELD-001408：类型为
的依赖项不满意，带有限定符@Default在
注入点[BackedAnnotatedField] @注入私有
ReportServiceFacadeBean.secondReport

WELD-001408: Unsatisfied dependencies for type SecondReportBean with qualifiers @Default at injection point [BackedAnnotatedField] @Inject private ReportServiceFacadeBean.secondReport

当我取消注释实现bean中的接口时，服务器启动没有任何错误。我在这里想念什么？

When I uncomment the interface in the implementing beans the server starts up without any error. What am I missing here?

推荐答案

与CDI Bean相比，EJB Bean具有一些不同的Bean类型，然后将其用于注入。也就是说，您将希望通过它们的客户端可见部分（即接口（除非您具有无接口视图））注入EJB bean。

EJB beans have a bit different bean types, which are then used for injection, compared to CDI beans. Namely you will want to inject EJB beans by their client-visible parts, meaning interfaces (unless you have no-interface view).

这完全受规范支持，这里是 CDI规范中的一章提到（

This is fully backed by spec, here is one chapter from CDI spec that mentions it (with links to other).

在您的情况下，您将必须引入限定符，然后注入如下所示的bean：

In your case you will have to introduce qualifiers and then inject the beans like:

@Inject
@SomeQualifier
ReportService firstService;

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