如何从bean调用函数

时间：2013-02-02 18:09:10

标签： jsf primefaces

一个非常简单的问题，但我无法解决问题，

我的xhtml页面有

                <p:commandButton action="#{NaviagationBean.buttonToUploadText}" value="Submit" icon ="ui-icon-arrowstop-1-n"/>

我想从存储在richard.fileupload中的NavigationBean.java中调用代码来调用此代码：

    public String buttonToUploadText() {
    System.out.println("buttonToUploadText invoked");
    return "/upload/uploadText.xhtml";
}

基本上我在xhtml中需要调用什么动作？打电话给这个？

代码atm显示此错误：

   WARNING: #{NavigationBean.buttonToUploadText}: javax.el.PropertyNotFoundException: /GUI/index.xhtml @61,130 action="#{NavigationBean.buttonToUploadText}": Target Unreachable, identifier 'NavigationBean' resolved to null
javax.faces.FacesException: #{NavigationBean.buttonToUploadText}: javax.el.PropertyNotFoundException: /GUI/index.xhtml @61,130 action="#{NavigationBean.buttonToUploadText}": Target Unreachable, identifier 'NavigationBean' resolved to null
    at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:118)
    at javax.faces.component.UICommand.broadcast(UICommand.java:315)
    at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794)
    at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259)
    at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1550)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:343)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:217)
    at org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:79)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:217)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:279)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:161)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:331)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
    at com.sun.enterprise.v3.services.impl.ContainerMapper$AdapterCallable.call(ContainerMapper.java:317)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:195)
    at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:860)
    at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:757)
    at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1056)
    at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:229)
    at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
    at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
    at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
    at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
    at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
    at java.lang.Thread.run(Thread.java:722)
Caused by: javax.faces.el.EvaluationException: javax.el.PropertyNotFoundException: /GUI/index.xhtml @61,130 action="#{NavigationBean.buttonToUploadText}": Target Unreachable, identifier 'NavigationBean' resolved to null
    at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:95)
    at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
    ... 36 more
Caused by: javax.el.PropertyNotFoundException: /GUI/index.xhtml @61,130 action="#{NavigationBean.buttonToUploadText}": Target Unreachable, identifier 'NavigationBean' resolved to null
    at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:107)
    at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88)
    ... 37 more

编辑

我这样做很好：

                <p:commandButton action="#{userBean.buttonToUploadText}" value="Submit" icon ="ui-icon-arrowstop-1-n"/>

使用UserBean.java中的代码

堆栈跟踪是：

WARNING: #{NavigationBean.buttonToUploadText}: javax.el.PropertyNotFoundException: /GUI/index.xhtml @61,130 action="#{NavigationBean.buttonToUploadText}": Target Unreachable, identifier 'NavigationBean' resolved to null
javax.faces.FacesException: #{NavigationBean.buttonToUploadText}: javax.el.PropertyNotFoundException: /GUI/index.xhtml @61,130 action="#{NavigationBean.buttonToUploadText}": Target Unreachable, identifier 'NavigationBean' resolved to null
    at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:118)
    at javax.faces.component.UICommand.broadcast(UICommand.java:315)
    at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794)
    at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259)
    at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1550)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:343)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:217)
    at org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:79)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:217)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:279)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:161)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:331)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
    at com.sun.enterprise.v3.services.impl.ContainerMapper$AdapterCallable.call(ContainerMapper.java:317)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:195)
    at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:860)
    at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:757)
    at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1056)
    at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:229)
    at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
    at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
    at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
    at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
    at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
    at java.lang.Thread.run(Thread.java:722)
Caused by: javax.faces.el.EvaluationException: javax.el.PropertyNotFoundException: /GUI/index.xhtml @61,130 action="#{NavigationBean.buttonToUploadText}": Target Unreachable, identifier 'NavigationBean' resolved to null
    at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:95)
    at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
    ... 36 more
Caused by: javax.el.PropertyNotFoundException: /GUI/index.xhtml @61,130 action="#{NavigationBean.buttonToUploadText}": Target Unreachable, identifier 'NavigationBean' resolved to null
    at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:107)
    at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88)
    ... 37 more

编辑2：

                <p:commandButton action="#{NaviagationBean.buttonToUploadText()}" value="Submit" icon ="ui-icon-arrowstop-1-n" ajax="False"/>

给了我相同的堆栈跟踪，但现在将我带到javax.el.PropertyNotFoundException: /GUI/index.xhtml @61,146 action="#{NaviagationBean.buttonToUploadText()}": Target Unreachable, identifier 'NaviagationBean' resolved to null

的页面

1 个答案:

答案 0 :(得分：3)

消息 Target Unreachable，标识符“NavigationBean”已解析为null 表示JSF框架无法找到您的托管bean。确保按如下方式编写bean：

@ManagedBean(name="NavigationBean")
@RequestScope
public class NavigationBean {

    public NavigationBean() {
    }

    public String buttonToUploadText() {
        System.out.println("buttonToUploadText invoked");
        return "/upload/uploadText.xhtml";
    }

    //other methods...
}

或者如果您使用CDI 

@Named("NavigationBean")
@RequestScope
public class NavigationBean {

    //...
}

另一种解决方案是在EL中使用navigationBean而不是NavigationBean：

<p:commandButton action="#{navigationBean.buttonToUploadText}" value="Submit"
    icon ="ui-icon-arrowstop-1-n" />
相关问题
最新问题