Question

我有一个@SessionScoped的课程和另一个@RequestScoped的课程。我想要做的是从@RequestScoped类访问SessionScoped类。我想通过将@SessionScoped类注入@RequestScoped类中的变量来简单地使用CDI，但是当我尝试通过该变量访问参数时，我最终会收到错误。

如何从@SessionScoped班级访问@RequestScoped班级的最佳方式？

SessionScoped类：

@ManagedBean(name = "globalBean", eager = true)
@Named
@SessionScoped
public class GlobalBean implements Serializable {
    private String language;

    public String getLanguage() {
        return language;
    }

    public void setLanguage(String language) {
        this.language = language;
    }
}

RequestScoped类：

@Named
@RequestScoped
public class TopMenuBean implements Serializable {
    //@Inject
    @ManagedProperty(value = "#{globalBean}")
    private GlobalBean global;

    public TopMenuBean() {
        this.global.setLanguage("en");
    }
}

错误：

20:23:32,214 SEVERE [javax.enterprise.resource.webcontainer.jsf.application] (default task-17) Error Rendering View[/index.xhtml]: java.lang.NullPointerException
    at com.mycategory.myprogram.TopMenuBean.<init>(TopMenuBean.java:84) [classes:]
    at com.mycategory.myprogram.TopMenuBean$Proxy$_$$_WeldClientProxy.<init>(Unknown Source) [classes:]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) [rt.jar:1.8.0_11]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) [rt.jar:1.8.0_11]
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) [rt.jar:1.8.0_11]
    at java.lang.reflect.Constructor.newInstance(Constructor.java:408) [rt.jar:1.8.0_11]
    at java.lang.Class.newInstance(Class.java:433) [rt.jar:1.8.0_11]
    at org.jboss.weld.security.NewInstanceAction.run(NewInstanceAction.java:33) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at java.security.AccessController.doPrivileged(Native Method) [rt.jar:1.8.0_11]
    at org.jboss.weld.bean.proxy.ProxyFactory.create(ProxyFactory.java:282) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyFactory.create(ClientProxyFactory.java:111) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider.createClientProxy(ClientProxyProvider.java:180) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider.createClientProxy(ClientProxyProvider.java:170) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider.access$100(ClientProxyProvider.java:45) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider$CreateClientProxy.load(ClientProxyProvider.java:56) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider$CreateClientProxy.load(ClientProxyProvider.java:52) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at com.google.common.cache.LocalCache$LoadingValueReference.loadFuture(LocalCache.java:3524)
    at com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2317)
    at com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2280)
    at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2195)
    at com.google.common.cache.LocalCache.get(LocalCache.java:3934)
    at com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:3938)
    at com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4821)
    at org.jboss.weld.util.cache.LoadingCacheUtils.getCacheValue(LoadingCacheUtils.java:52) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.util.cache.LoadingCacheUtils.getCastCacheValue(LoadingCacheUtils.java:80) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider.getClientProxy(ClientProxyProvider.java:186) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.el.AbstractWeldELResolver.lookup(AbstractWeldELResolver.java:110) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.el.AbstractWeldELResolver.getValue(AbstractWeldELResolver.java:91) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.as.jsf.injection.weld.ForwardingELResolver.getValue(ForwardingELResolver.java:46) [wildfly-jsf-injection-8.1.0.Final.jar:8.1.0.Final]
    at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:188) [jboss-el-api_3.0_spec-1.0.3.Final.jar:1.0.3.Final]
    at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at com.sun.el.parser.AstIdentifier.getValue(AstIdentifier.java:116) [javax.el-3.0.0.jar:]
    at com.sun.el.parser.AstValue.getBase(AstValue.java:151) [javax.el-3.0.0.jar:]
    at com.sun.el.parser.AstValue.getValue(AstValue.java:200) [javax.el-3.0.0.jar:]
    at com.sun.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:226) [javax.el-3.0.0.jar:]
    at org.jboss.weld.el.WeldValueExpression.getValue(WeldValueExpression.java:50) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.el.WeldValueExpression.getValue(WeldValueExpression.java:50) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at org.primefaces.component.tabmenu.TabMenu.getModel(TabMenu.java:84) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.menu.BaseMenuRenderer.encodeEnd(BaseMenuRenderer.java:103) [primefaces-5.1.jar:5.1]
    at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:919) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1864) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.render.Renderer.encodeChildren(Renderer.java:176) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:889) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:79) [primefaces-5.1.jar:5.1]
    at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:66) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.panelgrid.PanelGridRenderer.encodeRow(PanelGridRenderer.java:187) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.panelgrid.PanelGridRenderer.encodeStaticBody(PanelGridRenderer.java:147) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.panelgrid.PanelGridRenderer.encodeTableBody(PanelGridRenderer.java:100) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.panelgrid.PanelGridRenderer.encodeTableLayout(PanelGridRenderer.java:65) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.panelgrid.PanelGridRenderer.encodeEnd(PanelGridRenderer.java:37) [primefaces-5.1.jar:5.1]
    at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:919) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:83) [primefaces-5.1.jar:5.1]
    at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:66) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.layout.LayoutUnitRenderer.encodeEnd(LayoutUnitRenderer.java:49) [primefaces-5.1.jar:5.1]
    at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:919) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1864) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1860) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1860) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1860) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:461) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:133) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:337) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:337) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:120) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:219) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:647) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:61) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:113) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:56) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:45) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:61) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:58) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:70) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.security.handlers.SecurityInitialHandler.handleRequest(SecurityInitialHandler.java:76) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:240) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:227) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:73) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:146) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.server.Connectors.executeRootHandler(Connectors.java:177) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:727) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [rt.jar:1.8.0_11]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [rt.jar:1.8.0_11]
    at java.lang.Thread.run(Thread.java:745) [rt.jar:1.8.0_11]

20:23:32,227 ERROR [io.undertow.request] (default task-17) UT005023: Exception handling request to /myprogram/index.jsf: javax.servlet.ServletException
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:659) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:61) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:113) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:56) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:45) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:61) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:58) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:70) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.security.handlers.SecurityInitialHandler.handleRequest(SecurityInitialHandler.java:76) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:240) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:227) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:73) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:146) [undertow-servlet-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.server.Connectors.executeRootHandler(Connectors.java:177) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:727) [undertow-core-1.0.15.Final.jar:1.0.15.Final]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [rt.jar:1.8.0_11]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [rt.jar:1.8.0_11]
    at java.lang.Thread.run(Thread.java:745) [rt.jar:1.8.0_11]
Caused by: java.lang.NullPointerException
    at com.mycategory.myprogram.TopMenuBean.<init>(TopMenuBean.java:84) [classes:]
    at com.mycategory.myprogram.TopMenuBean$Proxy$_$$_WeldClientProxy.<init>(Unknown Source) [classes:]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) [rt.jar:1.8.0_11]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) [rt.jar:1.8.0_11]
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) [rt.jar:1.8.0_11]
    at java.lang.reflect.Constructor.newInstance(Constructor.java:408) [rt.jar:1.8.0_11]
    at java.lang.Class.newInstance(Class.java:433) [rt.jar:1.8.0_11]
    at org.jboss.weld.security.NewInstanceAction.run(NewInstanceAction.java:33) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at java.security.AccessController.doPrivileged(Native Method) [rt.jar:1.8.0_11]
    at org.jboss.weld.bean.proxy.ProxyFactory.create(ProxyFactory.java:282) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyFactory.create(ClientProxyFactory.java:111) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider.createClientProxy(ClientProxyProvider.java:180) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider.createClientProxy(ClientProxyProvider.java:170) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider.access$100(ClientProxyProvider.java:45) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider$CreateClientProxy.load(ClientProxyProvider.java:56) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider$CreateClientProxy.load(ClientProxyProvider.java:52) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at com.google.common.cache.LocalCache$LoadingValueReference.loadFuture(LocalCache.java:3524)
    at com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2317)
    at com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2280)
    at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2195)
    at com.google.common.cache.LocalCache.get(LocalCache.java:3934)
    at com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:3938)
    at com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4821)
    at org.jboss.weld.util.cache.LoadingCacheUtils.getCacheValue(LoadingCacheUtils.java:52) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.util.cache.LoadingCacheUtils.getCastCacheValue(LoadingCacheUtils.java:80) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.bean.proxy.ClientProxyProvider.getClientProxy(ClientProxyProvider.java:186) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.el.AbstractWeldELResolver.lookup(AbstractWeldELResolver.java:110) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.el.AbstractWeldELResolver.getValue(AbstractWeldELResolver.java:91) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.as.jsf.injection.weld.ForwardingELResolver.getValue(ForwardingELResolver.java:46) [wildfly-jsf-injection-8.1.0.Final.jar:8.1.0.Final]
    at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:188) [jboss-el-api_3.0_spec-1.0.3.Final.jar:1.0.3.Final]
    at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at com.sun.el.parser.AstIdentifier.getValue(AstIdentifier.java:116) [javax.el-3.0.0.jar:]
    at com.sun.el.parser.AstValue.getBase(AstValue.java:151) [javax.el-3.0.0.jar:]
    at com.sun.el.parser.AstValue.getValue(AstValue.java:200) [javax.el-3.0.0.jar:]
    at com.sun.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:226) [javax.el-3.0.0.jar:]
    at org.jboss.weld.el.WeldValueExpression.getValue(WeldValueExpression.java:50) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at org.jboss.weld.el.WeldValueExpression.getValue(WeldValueExpression.java:50) [weld-core-impl-2.1.2.Final.jar:2014-01-09 09:23]
    at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at org.primefaces.component.tabmenu.TabMenu.getModel(TabMenu.java:84) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.menu.BaseMenuRenderer.encodeEnd(BaseMenuRenderer.java:103) [primefaces-5.1.jar:5.1]
    at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:919) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1864) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.render.Renderer.encodeChildren(Renderer.java:176) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:889) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:79) [primefaces-5.1.jar:5.1]
    at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:66) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.panelgrid.PanelGridRenderer.encodeRow(PanelGridRenderer.java:187) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.panelgrid.PanelGridRenderer.encodeStaticBody(PanelGridRenderer.java:147) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.panelgrid.PanelGridRenderer.encodeTableBody(PanelGridRenderer.java:100) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.panelgrid.PanelGridRenderer.encodeTableLayout(PanelGridRenderer.java:65) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.panelgrid.PanelGridRenderer.encodeEnd(PanelGridRenderer.java:37) [primefaces-5.1.jar:5.1]
    at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:919) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:83) [primefaces-5.1.jar:5.1]
    at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:66) [primefaces-5.1.jar:5.1]
    at org.primefaces.component.layout.LayoutUnitRenderer.encodeEnd(LayoutUnitRenderer.java:49) [primefaces-5.1.jar:5.1]
    at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:919) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1864) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1860) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1860) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1860) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:461) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:133) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:337) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:337) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:120) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:219) [jsf-impl-2.2.6-jbossorg-4.jar:]
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:647) [jboss-jsf-api_2.2_spec-2.2.6.jar:2.2.6]
    ... 26 more

Answer 1

<强> [解决]：

混合JSF（@ManagedBean）和CDI（@Named）不是我的意图。我更喜欢专注于CDI并建立了一个工作实例，我想在这里发布那些有相同问题的灵魂。很长一段时间是我的一个错误：

不要尝试在构造函数中访问注入的变量！

非常感谢你的帮助！享受这个例子：

test.xhtml：

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:h="http://xmlns.jcp.org/jsf/html">
    <h:head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
    </h:head>
    <h:body>
        <h:outputText value="The language is: #{beanTwo.language}" />
    </h:body>
</html>

BeanOne.java：

import java.io.Serializable;
import javax.enterprise.context.SessionScoped;
import javax.inject.Named;

@Named
@SessionScoped
public class BeanOne implements Serializable {
    private String language;

    public String getLanguage() {
        return language;
    }

    public void setLanguage(String language) {
        this.language = language;
    }
}

BeanTwo.java：

import java.io.Serializable;
import javax.enterprise.context.RequestScoped;
import javax.inject.Inject;
import javax.inject.Named;

@Named
@RequestScoped
public class BeanTwo implements Serializable {
    @Inject
    private BeanOne beanOne;

    public String getLanguage() {
        this.beanOne.setLanguage("de");
        return this.beanOne.getLanguage();
    }
}

从@RequestScoped类访问@SessionScoped类？

1 个答案: