Java UploadedFile-NullPointerException_Java_Jsf_File Upload_Primefaces

Java UploadedFile-NullPointerException

java jsf file-upload primefaces

Java UploadedFile-NullPointerException,java,jsf,file-upload,primefaces,Java,Jsf,File Upload,Primefaces,根据演示中给出的示例，我正在尝试fileupload Primefaces 3.0的组件。我还添加了commons-fileupload-1.2.2.jar和commons-io-2.0.1.jar以及primefaces-3.1.jar文件我运行了上传程序，我得到了一个java.lang.NullPointerException。有人能帮我解决这个问题吗？我已经在互联网上搜索了很多次，找不到有效的解决方案我正在使用NetBeans 7.2.1和GlassFish进行部署我的代码： XHT

根据演示中给出的示例，我正在尝试fileupload Primefaces 3.0的组件。我还添加了commons-fileupload-1.2.2.jar和commons-io-2.0.1.jar以及primefaces-3.1.jar文件

我运行了上传程序，我得到了一个java.lang.NullPointerException。有人能帮我解决这个问题吗？我已经在互联网上搜索了很多次，找不到有效的解决方案

我正在使用NetBeans 7.2.1和GlassFish进行部署

我的代码： XHTML：

<h:form id="frm" enctype="multipart/form-data">  
        <table>
            <tr><td><div style="height:300px;"><img src="images/adcar.jpg" style="top:0px;"/>
                    </div>
                    </td>
                <td>
                    <h:form id="img" enctype="multipart/form-data">
 <div style=" -moz-border-radius:15px;  border:1px solid;  width:600px; border-color:#930303;">
    <br></br>
        <p:panel style="border:none;">
         <p:messages></p:messages>
        </p:panel>
        <h:panelGrid columns="2">
           <h:outputText value="Nom Projet :"/>
           <h:inputText id="Nom" value="#{ajoutprjt.nomProjet}" />
           <h:outputText value="Ref Projet :"></h:outputText><h:inputText value="#{ajoutprjt.idProjet}" />
           <h:outputText value="Date de Début :"></h:outputText><h:inputText value="#{ajoutprjt.dateDeb}" />
           <h:outputText value="Date de Fin :"></h:outputText><h:inputText value="#{ajoutprjt.dateFin}" />
           <h:outputText value="Chef  :"></h:outputText>
           <h:selectOneMenu value="#{ajoutprjt.idChef}">
               <f:selectItem itemValue="#{null}" itemLabel="-- select one --" />
               <f:selectItems value="#{ajoutprjt.tdata}" var="cmd" 
                                             itemValue="#{cmd.id}" itemLabel="#{cmd.id} #{cmd.nom} #{cmd.prenom}" />
           </h:selectOneMenu>
           Documents : <p:fileUpload value="#{ajoutprjt.file}" id="fileupload"   mode="simple"></p:fileUpload>
           <h:outputText></h:outputText><p:panel style="border: none;"><p:commandButton value="Ajouter" action="#{ajoutprjt.ajoutP}" ajax="false"></p:commandButton><p:commandButton value="Annuler" action="#{ajoutprjt.annuleraj}" ajax="false"></p:commandButton></p:panel>
       </h:panelGrid>
         </div>
                    </h:form>
     </td></tr>  </table>
        </h:form>[/code]

在xhtml页面中，使用

actionListener

而不是

action

，如下所示

<p:commandButton value="Ajouter" actionListener="#{ajoutprjt.ajoutP}"
 ajax="false"></p:commandButton>

你在那页上似乎有很多东西。以下是我如何调试此程序的方法：

如果尚未下载所有依赖项（如果已下载，请仔细检查您的工作）。下面是依赖项的定义

使用PrimeFace网站上的这个例子，只需创建一个单独的文件上传控制器，并像现在这样查看页面

首先尝试让上面的步骤正常工作，一旦完成了，然后开始慢慢地将这些元素添加到现有的JSF页面和控制器中，并进行更改以适应您的需求（从零开始，而不是使用您已经在该页面上修改和发布的内容）

我注意到一件事：

我看到您有嵌套的enctype=“多部分/表单数据”这可能是导致空值的原因之一，因为一个页面中有太多这样的内容，而您的控制器只得到其中一个，但这只是一个经过教育的观察结果，您可能希望在经历我上面为您列出的所有问题/步骤之前进行调试和研究

我不明白如何在“actionListener”上使用此方法“ajoupp”，如follow“actionListener=“#{ajoupprjt.ajoupp}”，以便在方法“ajoupp”（FileUploadEvent事件）中有一个参数“。生成以下错误«javax.el.MethodNotFoundException»
可能重复感谢我将按照此步骤返回replayWelcome，很高兴我能提供帮助。Message=未找到方法：com.x.web。MyBean@6ff23e74.onSubmitClicked()
<?xml version="1.0" encoding="UTF-8"?> <web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"> <context-param> <param-name>javax.faces.PROJECT_STAGE</param-name> <param-value>Development</param-value> </context-param> <context-param> <param-name>primefaces.THEME</param-name> <param-value>aristo</param-value> </context-param> <servlet> <servlet-name>Faces Servlet</servlet-name> <servlet-class>javax.faces.webapp.FacesServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>Faces Servlet</servlet-name> <url-pattern>*.xhtml</url-pattern> <url-pattern>/faces/*</url-pattern> </servlet-mapping> <session-config> <session-timeout> 30 </session-timeout> </session-config> <welcome-file-list> <welcome-file>faces/auth.xhtml</welcome-file> </welcome-file-list> <resource-ref> <description>Base de données pour app Ontologie Projet master Pro</description> <res-ref-name>jdbc/gcn</res-ref-name> <res-type>javax.sql.DataSource</res-type> <res-auth>Container</res-auth> <res-sharing-scope>Shareable</res-sharing-scope> </resource-ref> <filter> <filter-name>PrimeFaces FileUpload Filter</filter-name> <filter-class> org.primefaces.webapp.filter.FileUploadFilter </filter-class> </filter> <filter-mapping> <filter-name>PrimeFaces FileUpload Filter</filter-name> <servlet-name>Faces Servlet</servlet-name> <dispatcher>FORWARD</dispatcher> </filter-mapping> </web-app>

javax.faces.el.EvaluationException: java.lang.NullPointerException at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:102) at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102) 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.StandardWrapperValve.invoke(StandardWrapperValve.java:281) 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: java.lang.NullPointerException at beans.ajoutprjt.ajoutP(ajoutprjt.java:176) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:601) at com.sun.el.parser.AstValue.invoke(AstValue.java:254) at com.sun.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:302) at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105) at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88) ... 32 more

<p:commandButton value="Ajouter" actionListener="#{ajoutprjt.ajoutP}" ajax="false"></p:commandButton>

public void ajoutP(FileUploadEvent event){ OutputStream out=null; InputStream fileContent=null; try{ UploadedFile uploadedFile= event.getFile(); out= new FileOutputStream(new File("D:/")+uploadedFile.getFileName()); fileContent= uploadedFile.getInputstream(); int read=0; final byte[] bytes= new byte[1024]; while((read= fileContent.read(bytes))!=-1){ out.write(bytes,0,read); } } catch(FileNotFoundException fnfe){ } catch(IOException ioex){ } }