如果EJB bean方法是包私有的,为什么不检测它？

Question

这个让我很困惑.我创建了一个基于在Wildfly 10.1上运行的JavaEE7的最小JAX-RS应用程序.

@ApplicationPath("")
public class JAXRSConfiguration extends Application {

    @Override
    public Set<Class<?>> getClasses() {
        return new HashSet<Class<?>>(Arrays.asList(Resource.class));
    }
}

资源注入一个虚拟无状态bean:

@Path("")
public class Resource {

    @Inject
    Manager manager;

    @GET
    @Path("/go")
    public void go() {
        manager.call();
    }
}

这是豆子:

@Stateless
public class Manager {

    @PostConstruct
    private void init() {
        System.out.println("POST CONSTRUCT ");
    }

    void call() {
        System.out.println("called ");
    }
}

使用浏览器执行GET会导致以下错误:

org.jboss.resteasy.spi.UnhandledException: org.jboss.weld.exceptions.WeldException: Class org.jboss.weld.util.reflection.Reflections can not access a member of class com.a.b.Manager with modifiers ""

可以发布完整堆栈跟踪,但所有引发的消息都是相同的.

我搜索了这个错误,它发生在注入的bean 不公开的时候,但我的是.我决定试图移除公众,看看它会抱怨什么,并且...它的工作原理.注入bean,注入任何可能注入的注入,调用post构造方法并打印所有打印件.

这与ejb无国籍阶级必须公开形成鲜明对比吗？.这里发生了什么？

更新

Oliv37促使我做了一些测试,以下是调查结果:

• 如果call是package的话,那只有当工作Manager是package.
• 如果call是public,它无论如何都有效.
• 如果call是final,该@PostConstruct方法被称为只有当Manager是package.

现在问题变成:为什么该方法需要公开才能使CDI检测起作用,为什么最终导致后构造方法如果该类是公共的则不会被调用？

UPDATE2

完整堆栈跟踪:

org.jboss.resteasy.spi.UnhandledException: org.jboss.weld.exceptions.WeldException: Class org.jboss.weld.util.reflection.Reflections can not access a member of class com.a.b.Manager with modifiers ""
    at org.jboss.resteasy.core.ExceptionHandler.handleApplicationException(ExceptionHandler.java:77)
    at org.jboss.resteasy.core.ExceptionHandler.handleException(ExceptionHandler.java:220)
    at org.jboss.resteasy.core.SynchronousDispatcher.writeException(SynchronousDispatcher.java:175)
    at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:418)
    at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:209)
    at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:221)
    at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56)
    at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
    at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85)
    at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62)
    at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36)
    at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131)
    at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46)
    at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64)
    at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60)
    at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77)
    at io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50)
    at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:292)
    at io.undertow.servlet.handlers.ServletInitialHandler.access$100(ServletInitialHandler.java:81)
    at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:138)
    at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135)
    at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48)
    at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:272)
    at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81)
    at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:104)
    at io.undertow.server.Connectors.executeRootHandler(Connectors.java:202)
    at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:805)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)
Caused by: org.jboss.weld.exceptions.WeldException: Class org.jboss.weld.util.reflection.Reflections can not access a member of class com.a.b.Manager with modifiers ""
    at org.jboss.weld.util.reflection.Reflections.invokeAndUnwrap(Reflections.java:437)
    at org.jboss.weld.bean.proxy.EnterpriseBeanProxyMethodHandler.invoke(EnterpriseBeanProxyMethodHandler.java:128)
    at org.jboss.weld.bean.proxy.EnterpriseTargetBeanInstance.invoke(EnterpriseTargetBeanInstance.java:56)
    at org.jboss.weld.bean.proxy.InjectionPointPropagatingEnterpriseTargetBeanInstance.invoke(InjectionPointPropagatingEnterpriseTargetBeanInstance.java:67)
    at org.jboss.weld.bean.proxy.ProxyMethodHandler.invoke(ProxyMethodHandler.java:100)
    at com.a.b.Manager$Proxy$_$$_Weld$EnterpriseProxy$.call(Unknown Source)
    at com.airhacks.boundary.Resource.go(Resource.java:16)
    at com.airhacks.boundary.Resource$Proxy$_$$_WeldClientProxy.go(Unknown Source)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.jboss.resteasy.core.MethodInjectorImpl.invoke(MethodInjectorImpl.java:139)
    at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTarget(ResourceMethodInvoker.java:295)
    at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:249)
    at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:236)
    at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:402)
    ... 42 more
Caused by: java.lang.IllegalAccessException: Class org.jboss.weld.util.reflection.Reflections can not access a member of class com.a.b.Manager with modifiers ""
    at sun.reflect.Reflection.ensureMemberAccess(Reflection.java:102)
    at java.lang.reflect.AccessibleObject.slowCheckMemberAccess(AccessibleObject.java:296)
    at java.lang.reflect.AccessibleObject.checkAccess(AccessibleObject.java:288)
    at java.lang.reflect.Method.invoke(Method.java:491)
    at org.jboss.weld.util.reflection.Reflections.invokeAndUnwrap(Reflections.java:433)
    ... 58 more

Answer 1

简短的回答是 - 让你的call方法公开

这样的时间越长 - 这里的问题是你的call方法受到包保护.根据EJB规范,章节会话Bean的无接口视图(引自3.1 EJB规范):

只能通过无接口视图调用bean类(以及任何超类)的公共方法.通过无接口视图引用尝试使用任何其他访问修饰符调用方法必须导致a javax.ejb.EJBException.

通过使用非公共修饰符,您违反了规范,并且EJBException可以在WFLY中的EJB impl或功能中忽略in not throw .无论如何,你处于灰色的未指定区域.

现在和Weld一样 - 它试图使用反射来访问该方法并调用它,故意不在调用之前使其可访问.这是显而易见的,因为如果没有绕过它(没有Method.setAccessible()),你就无法访问其他方法.

至于你关于final方法的问题而@PostConstruct不是被调用 - 你正在破坏另一个EJB规则.这个是4.9.8 Session Bean’s No-Interface View其中一个破折号说:

只能java.lang.Object声明bean类的私有方法和除超类之外的任何超类final.

我不能说为什么没有例外,但这是你头痛的原因.至于为什么这个规则存在 - 正如我在评论中所说,Weld需要创建代理,如果方法不能被覆盖,则不可能编织@PostConstruct调用并拦截它.

希望这能回答您的疑问.