球衣注入 AbstractBinder 没有调用配置

jersey injection AbstractBinder isn't calling configure

答案:

非常感谢所有看过这篇文章的人,尤其是@Andbdrew。在他的帮助下,我让它工作了,代码在 https://github.com/dabraham02124/injection/tree/feature 。我将看看我是否可以减少它 "annotations do magic",并且实际上有代码调用其他代码,但它正在 "feature" 分支上工作。


原问题:

我正在尝试在 jersey 2.7 应用程序中注入资源。它不工作。我收到以下错误:

2019-04-20 22:06:06,004 WARN [qtp1142020464-16] o.e.j.s.ServletHandler - javax.servlet.ServletException: A MultiException has 3 exceptions. They are: 1. org.glassfish.hk2.api.UnsatisfiedDependencyException: There was no object available for injection at Injectee(requiredType=StringHolder,parent=EntryPoint,qualifiers={}),position=-1,optional=false,self=false,unqualified=null,1295211193) 2. java.lang.IllegalArgumentException: While attempting to resolve the dependencies of org.sweatshop.injection.EntryPoint errors were found 3. java.lang.IllegalStateException: Unable to perform operation: resolve on org.sweatshop.injection.EntryPoint

我已经遵循了我在所有教程中看到的所有内容,例如但不限于;

我试过在不同的地方添加各种注释,我已经阅读了我能找到的所有 Whosebug 页面,我没有看到任何变化。

最小的例子可以在 https://github.com/dabraham02124/injection 找到。第一次提交没有注入,并且有效。第二次提交确实有注入和抛出。

对于那些想查看此页面上的代码的人,这里是我认为 重要的部分:

资源class

@Path("/")
@RequestScoped
public class EntryPoint {
    @Inject
    public StringHolder stringHolder;

    @GET
    @Produces(MediaType.TEXT_HTML)
    public Response homePage() {
        return Response.ok(stringHolder.getString()).build();
    }
}

应用class

@ApplicationPath("/")
public class App extends ResourceConfig {
    private final MyServer jettyServer;
    private static final org.slf4j.Logger log = org.slf4j.LoggerFactory.getLogger(App.class);

    public App(MyServer jettyServer) {
        this.jettyServer = jettyServer;
    }

    public static void main(String[] args) throws Exception {
        final ServletContextHandler context = getContext();
        final MyServer jettyServer = new MyServer(8080, context);
        prepJettyServlet(context);

        log.info("about to start up");
        new App(jettyServer).runServer();
    }

    private void register() {
        log.info("start register");

        register(EntryPoint.class);
        register(StringHolder.class);
        register(new AbstractBinder() {
            @Override
            protected void configure() {
                log.info("start bind singleton"); //These three lines never get called
                bind(new StringHolder("injected string")).to(StringHolder.class);
                log.info("end bind singleton");
            }
        });

        log.info("end register");
    }

注入单例class

@RequestScoped
public class StringHolder {

    private final String string;

    public StringHolder(String string) {
        this.string = string;
    }

    public String getString() {
        return string;
    }
}

有趣的是,日志显示我在 Binder 上调用 register,但我从未看到 configure 被调用的证据。

帮忙?我正在拔头发,我已经秃了...

您可以使用 Feature 来完成此操作,如 this answer 中所述(我无法让他们的第一种方法与您的球衣版本相匹配)。

@Provider
public final class StartupListener implements Feature {

    private final ServiceLocator serviceLocator;

    @Inject
    public StartupListener(ServiceLocator serviceLocator) {
        this.serviceLocator = serviceLocator;
    }

    @Override
    public boolean configure(FeatureContext context) {
        ServiceLocatorUtilities.bind(serviceLocator, new AbstractBinder() {
            @Override
            protected void configure() {
                bind(new StringHolder("injected string")).to(StringHolder.class);
            }
        });
        return true;
    }
}