使用 Tomahawk 提交 jsf 上传请求时 UploadedFile 为空

Question

尝试使用 Tomahawk2.0 1.1.11 在 facelets 页面上上传文件。但是我得到一个空指针异常，我在调试器中看到，uploadFile 变量没有在 bean 中设置。任何想法为什么没有设置bean？ t:inputFileUpload 组件按我的预期呈现和运行。

页面：

<h:form enctype="multipart/form-data">
<t:inputFileUpload value="#{Bean.uploadedFile}" />
<h:commandButton type="submit" id="Submit" value="Submit" action="#{Bean.submit}"/>
<h:messages />  
</h:form>

豆子：

protected UploadedFile uploadedFile;
public UploadedFile getUploadedFile() { return this.uploadedFile; }
public void setUploadedFile(UploadedFile uploadedFile) {
this.uploadedFile = uploadedFile;}

public String submit()  throws IOException { 
String fileName = FilenameUtils.getName(uploadedFile.getName()); // exception here!!
String contentType = uploadedFile.getContentType();
byte[] bytes = uploadedFile.getBytes();
FacesContext.getCurrentInstance().addMessage(null, 
new FacesMessage(String.format("File '%s' of type '%s' successfully uploaded!", 
fileName, contentType)));

return "success";     
}

异常发生在提交的第一行。在调试器中，我看到uploadedFile 为空。 jsf 页面看起来不错，我可以使用浏览按钮选择文件。按提交后，我看到 bean 中的上传文件为空。

错误信息：

16:06:59,699 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/Framework].[Faces Servlet]] (http--127.0.0.1-8080-2) Servlet.service() for servlet Faces Servlet threw exception: java.lang.NullPointerException
    at net.gui.bean.Bean.submit(Bean.java:118) [classes:]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [:1.6.0_30]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) [:1.6.0_30]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) [:1.6.0_30]
    at java.lang.reflect.Method.invoke(Method.java:597) [:1.6.0_30]
    at org.apache.el.parser.AstValue.invoke(AstValue.java:196) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:276) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105) [jsf-impl-2.1.3-b02-jbossorg-2.jar:2.1.3-SNAPSHOT]
    at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88) [jboss-jsf-api_2.1_spec-2.0.0.Beta1.jar:2.0.0.Beta1]
    at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102) [jsf-impl-2.1.3-b02-jbossorg-2.jar:2.1.3-SNAPSHOT]
    at javax.faces.component.UICommand.broadcast(UICommand.java:315) [jboss-jsf-api_2.1_spec-2.0.0.Beta1.jar:2.0.0.Beta1]
    at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794) [jboss-jsf-api_2.1_spec-2.0.0.Beta1.jar:2.0.0.Beta1]
    at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259) [jboss-jsf-api_2.1_spec-2.0.0.Beta1.jar:2.0.0.Beta1]
    at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81) [jsf-impl-2.1.3-b02-jbossorg-2.jar:2.1.3-SNAPSHOT]
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.1.3-b02-jbossorg-2.jar:2.1.3-SNAPSHOT]
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) [jsf-impl-2.1.3-b02-jbossorg-2.jar:2.1.3-SNAPSHOT]
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593) [jboss-jsf-api_2.1_spec-2.0.0.Beta1.jar:2.0.0.Beta1]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.1.Final.jar:7.0.2.Final] 
    at org.apache.myfaces.webapp.filter.ExtensionsFilter.doFilter(ExtensionsFilter.java:357) [tomahawk20-1.1.11.jar:] 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.1.Final.jar:7.0.2.Final] 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at net.gui.filter.HibernateSessionRequestFilter.doFilter(HibernateSessionRequestFilter.java:34) [classes:] 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.1.Final.jar:7.0.2.Final] 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at net.gui.filter.NAISAuthFilter.doFilter(NAISAuthFilter.java:59) [classes:] 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.1.Final.jar:7.0.2.Final] 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:139) [jboss-as-web-7.0.2.Final.jar:7.0.2.Final]
    at org.jboss.as.web.NamingValve.invoke(NamingValve.java:57) [jboss-as-web-7.0.2.Final.jar:7.0.2.Final]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:154) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:362) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:667) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:952) [jbossweb-7.0.1.Final.jar:7.0.2.Final] 
    at java.lang.Thread.run(Thread.java:662) [:1.6.0_30]

web.xml：

<filter>
<filter-name>MyFacesExtensionsFilter</filter-name>
    <filter-class>org.apache.myfaces.webapp.filter.ExtensionsFilter</filter-class>
</filter>

<filter-mapping>
    <filter-name>MyFacesExtensionsFilter</filter-name>
    <servlet-name>Faces Servlet</servlet-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>    

<filter>
    <filter-name>NaisAuth</filter-name>
    <filter-class>net.gui.filter.NAISAuthFilter</filter-class>
</filter>

<filter-mapping>
    <filter-name>NaisAuth</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

<filter>
<filter-name>HibernateFilter</filter-name>
<filter-class> net.gui.filter.HibernateSessionRequestFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>HibernateFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

Answer 1

当NAISAuthFilter 或HibernateSessionRequestFilter 事先通过getParameter()、getReader() 等访问请求正文时，可能会发生这种情况。这样，请求正文在ExtensionsFilter 有机会执行之前已经被解析它。

要么修复这些过滤器，要么重新排列web.xml 中ExtensionsFilter 的映射，以便在这些过滤器之前声明。

另一个可能的原因是您实际上将多个<h:form> 组件相互嵌套。这将导致非法的 HTML 语法，并且浏览器行为未指定处理表单提交。您需要确保您没有嵌套表单（但并行的多个表单是完全有效的）。