依赖注入到ResourceFilter中不起作用? [英] Dependency injection into ResourceFilter not working?

问题描述

我有一堆JAX-RS资源，它们为新的WebService提供API.为了了解正在发生的事情，我想将有关每个请求的信息存储在数据仓库中.在我看来，这是跨领域关注的完美示例，可以通过ResourceFilter来实现，对吧?

I have a bunch of JAX-RS resources that provide an API for a new WebService. In order to understand what's happening, I'd like to store information about each request in a data warehouse. In my mind, this is a perfect example for a cross-cutting concern, which could be implemented by a ResourceFilter, right?

所以我建立了一个DataWarehouseService，它应该将内容存储在数据库中:

So I built a DataWarehouseService which is supposed to store stuff in the DB:

@Stateless
@LocalBean
public class DataWarehouseService {

    public void logApiCall(ContainerRequest cr) {
        // get interesting fields from request, store in DB
        ...
    }
}

这是我的过滤器:

public class LoggingResourceFilter implements ResourceFilter {

    Logger log = Logger.getLogger(this.getClass().getName());

    @EJB
    DataWarehouseService dwh;

    @Override
    public ContainerRequestFilter getRequestFilter() {

        return new ContainerRequestFilter() {
            @Override
            public ContainerRequest filter(ContainerRequest cr) {
                log.info("Incoming request: "+
                        cr.getHeaderValue("user-agent") +" "+
                        cr.getMethod() +" "+
                        cr.getPath()
                        );

                dwh.logApiRequest(cr);
                return cr;
            }
        };
    }

    @Override
    public ContainerResponseFilter getResponseFilter() {
        return null;
    }
}

我通过类级别的注释@ResourceFilters(LoggingResourceFilter.class)将过滤器注入到我的JAX-RS资源中.

I inject the filter into my JAX-RS resources via annotation @ResourceFilters(LoggingResourceFilter.class) on class-level.

当我访问JAX-RS资源之一时，Filter-injection工作正常，日志语句("Incoming request:...")被执行.但是之后，立即使用Nullpointer调用注入的DataWarehouseService的dwh.logApiRequest(cr)失败-显然注入失败了！！

The Filter-injection works fine, when I access one of the JAX-RS resources, the log statement ("Incoming request: ...") gets executed. But immediately afterwards, the call to the injected DataWarehouseService's dwh.logApiRequest(cr) fails with a Nullpointer - obviously the injection failed?!

这是什么问题?我以为，ResourceFilters是托管的，可以使用CDI.我错了吗?

What's the problem here? I thought, ResourceFilters are managed and can use CDI. Am I wrong?

所有这些都在Glassfish 3.1.1上运行，Jersey 1.8是JAX-RS提供程序.如果我使用@Inject会有所不同吗?

All of this runs on Glassfish 3.1.1, Jersey 1.8 is the JAX-RS provider. Would it make a difference if I used @Inject?

推荐答案

好，我是个白痴.

在LoggingResourceFilter上添加@Stateless批注以对其进行修复.

Adding a @Stateless annotation to the LoggingResourceFilter fixed it.

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