jsf - 当名为 cid 的查询字符串参数附加到 URL 时，摆脱 org.jboss.weld.context.NonexistentConversationException

Question

如下所示获取一个简单的 CDI(它也可以是 JSF 托管 bean)bean。

import java.io.Serializable;    
import javax.inject.Named;
import javax.faces.view.ViewScoped;

@Named
@ViewScoped
public class TestManagedBean implements Serializable
{
    private static final long serialVersionUID=1L;

    public TestManagedBean() {}
}

如果 XHTML 页面使用名为 cid 的查询字符串参数访问此 bean，这是 @ConversationScoped CDI 管理的 bean 所必需的(可能有意/无意地也被最终用户追加)，抛出如下所示的异常。

Severe:   Error Rendering View[/Test.xhtml]
org.jboss.weld.context.NonexistentConversationException: WELD-000321: No conversation found to restore for id 1
    at org.jboss.weld.context.AbstractConversationContext.initialize(AbstractConversationContext.java:259)
    at org.jboss.weld.context.http.LazyHttpConversationContextImpl.initialize(LazyHttpConversationContextImpl.java:68)
    at org.jboss.weld.context.http.LazyHttpConversationContextImpl.checkContextInitialized(LazyHttpConversationContextImpl.java:93)
    at org.jboss.weld.context.AbstractConversationContext.getCurrentConversation(AbstractConversationContext.java:445)
    at org.jboss.weld.jsf.ConversationAwareViewHandler.getActionURL(ConversationAwareViewHandler.java:111)
    at com.sun.faces.renderkit.html_basic.FormRenderer.getActionStr(FormRenderer.java:250)
    at com.sun.faces.renderkit.html_basic.FormRenderer.encodeBegin(FormRenderer.java:143)
    at javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:864)
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1854)
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1859)
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1859)
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:456)
    at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:133)
    at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:337)
    at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:337)
    at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:120)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:219)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:647)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:415)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:282)
    at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:459)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:167)
    at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:201)
    at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:175)
    at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:235)
    at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:284)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:201)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:133)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:112)
    at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
    at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:561)
    at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:565)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:545)
    at java.lang.Thread.run(Thread.java:745)

Warning:   StandardWrapperValve[Faces Servlet]: Servlet.service() for servlet Faces Servlet threw exception
org.jboss.weld.context.NonexistentConversationException: WELD-000321: No conversation found to restore for id 1
    at org.jboss.weld.context.AbstractConversationContext.initialize(AbstractConversationContext.java:259)
    at org.jboss.weld.context.http.LazyHttpConversationContextImpl.initialize(LazyHttpConversationContextImpl.java:68)
    at org.jboss.weld.context.http.LazyHttpConversationContextImpl.checkContextInitialized(LazyHttpConversationContextImpl.java:93)
    at org.jboss.weld.context.AbstractConversationContext.getCurrentConversation(AbstractConversationContext.java:445)
    at org.jboss.weld.jsf.ConversationAwareViewHandler.getActionURL(ConversationAwareViewHandler.java:111)
    at com.sun.faces.renderkit.html_basic.FormRenderer.getActionStr(FormRenderer.java:250)
    at com.sun.faces.renderkit.html_basic.FormRenderer.encodeBegin(FormRenderer.java:143)
    at javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:864)
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1854)
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1859)
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1859)
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:456)
    at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:133)
    at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:337)
    at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:337)
    at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:120)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:219)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:647)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:415)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:282)
    at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:459)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:167)
    at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:201)
    at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:175)
    at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:235)
    at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:284)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:201)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:133)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:112)
    at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
    at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:561)
    at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:565)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:545)
    at java.lang.Thread.run(Thread.java:745)

即使将名为 cid 的参数附加到 URL，是否仍然可以避免此异常？

Answer 1

这特定于 Weld(实现)，而不是 CDI(API)。在当前的 Weld 2.2.x 版本中，没有简单或 native 的方法来禁用它。然而，Weld 允许您通过 HttpConversationContext#setParameterName() 将请求参数名称 cid 更改为其他名称。 .您可以将其设置为例如一个java.util.UUID应用程序启动期间的值。

import javax.faces.bean.ManagedBean;
import javax.faces.bean.ApplicationScoped;
import org.jboss.weld.context.http.HttpConversationContext;

@ManagedBean(eager=true)
@ApplicationScoped
public class Application {

    @Inject
    private HttpConversationContext conversationContext;

    @PostConstruct
    public void init() {
        hideConversationScope();
    }

    /**
     * "Hide" conversation scope by replacing its default "cid" parameter name
     * by something unpredictable.
     */
    private void hideConversationScope() {
        conversationContext.setParameterName(UUID.randomUUID().toString());
    }

}

不幸的是，CDI 没有任何与 eager=true 等效的东西。或者，如果您手头有 EJB:

import javax.ejb.Startup;
import javax.ejb.Singleton;

@Startup
@Singleton
public class Application {

(您可能想要添加 @TransactionAttribute(NOT_SUPPORTED) 以关闭周围不必要的数据库事务管理)

或者，如果您有 OmniFaces在手:

import org.omnifaces.cdi.Startup;

@Startup
public class Application {