Struts 2文件上传 - 空指针异常 [英] Struts 2 File Upload - Null Pointer Exception

问题描述

信息范读预范读亦范中亦会读范亦亦读亦读但是，在到达我的动作类之后，我的文件 filename 和文件内容类型都以 null 出现。我试图寻找这个问题，但没有结果。以下是我的文件上传代码。

index.jsp ：

 <％@ taglib prefix =suri =/ struts-tags％> 
< html> 
< head> 
< s：head /> 
< / head> 
< s：actionerror /> 
< s：form action =uploadActionmethod =POSTenctype =multipart / form-data> 
 
< s：file name =fileUploadlabel =选择文件size =40/> 
 
< s：submit value =Uploadname =submit/> 
 
< / s：form> 
  

Struts.xml

 <？xml version =1.0encoding =UTF-8？> 
 
<！DOCTYPE struts PUBLIC 
 -  // Apache Software Foundation // DTD Struts Configuration 2.0 // EN
http://struts.apache.org/的DTD /支杆-2.0.dtd> 
 
< struts> 
< include file =struts-default.xml/> 
< package name =aextends =struts-default> 
 
< action name =resultActionclass =ManagePlanDataFileUploadActionBeanmethod =executeFileUploadDemo> 
 
< interceptor-ref name =fileUpload> 
< param name =maximumSize> 10240< / param> 
< param name =allowedTypes> text / plain< / param> 
< / interceptor-ref> 
< interceptor-ref name =defaultStack/> 
< result name =success> displayResultsJSP< / result> 
 
< / action> 
< / package> 
< / struts> 
  

applicationContext-web.xml

<？xml version =1.0encoding =UTF-8？>
< beans xmlns =http://www.springframework.org/schema/beans
xmlns：xsi =http://www.w3.org/2001/XMLSchema-instancexmlns ：jee =http://www.springframework.org/schema/jee
xmlns：aop =http://www.springframework.org/schema/aopxmlns：tx =http：// www.springframework.org/schema/tx
xsi：schemaLocation =http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/ spring-beans-2.0.xsd
http://www.springframework.org/schema/jee
http://www.springframework.org/schema/jee/spring-jee-2.0.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-2.0.xsd
http：// www .springframework.org / schema / tx
http://www.springframework.org/schema/tx/spring-tx-2.0.xsd\">
< bean id =ManagePlanDataFileUploadActionBeanscope =prototype

class =com.hix.action.planmanagement.ManagePlanDataFileUploadAction>

< / bean>
< / beans>


ManagePlanUploadAction
< pre class =lang-java prettyprint-override> package com.hix.action.planmgmt;

import java.io.File;

import javax.servlet.http.HttpServletRequest;

导入org.apache.commons.io.FileUtils;

import com.opensymphony.xwork2.ActionSupport;

public class ManagePlanUploadAction extends ActionSupport {

private HttpServletRequest request;

私人档案fileUpload;
private String fileUploadContentType;
private String fileUploadFileName;

public void setServletRequest（HttpServletRequest paramHttpServletRequest）{
this.request = paramHttpServletRequest;
}

public HttpServletRequest getServletRequest（）{
return request;

$ b $ public File getFileUpload（）{
return fileUpload;
}

public void setFileUpload（File fileUpload）{
this.fileUpload = fileUpload;


public String getFileUploadContentType（）{
return fileUploadContentType;
}

public void setFileUploadContentType（String fileUploadContentType）{
this.fileUploadContentType = fileUploadContentType;
}

public String getFileUploadFileName（）{
return fileUploadFileName;
}

public void setFileUploadFileName（String fileUploadFileName）{
this.fileUploadFileName = fileUploadFileName;
}

public String executeFileUploadDemo（）throws Exception {
try {
String filePath =C：/ Myuploads2;
System.out.println（Server path：+ filePath）;
文件fileToCreate =新文件（filePath，fileUploadFileName）;
FileUtils.copyFile（fileUpload，fileToCreate）;
} catch（Exception e）{
e.printStackTrace（）;信范读范范辛亦读范辛预预读亦亦辛中中预秘
回报SUCCESS;
}
System.out.println（File：+ fileUpload）;
System.out.println（Filename：+ fileUploadFileName）;
System.out.println（File type：+ fileUploadContentType）;
回报SUCCESS;




tiles-def.xml
$ b

<！DOCTYPE tiles-definitions PUBLIC
- // Apache Software Foundation // DTD Tiles Configuration 2.0 // EN
http://tiles.apache.org/dtds/tiles-config_2_0.dtd\">

< tiles-definitions>

< put-attribute name =headervalue =/ jsp / template / defaultHeader.jsp/>

< put-attribute name =footervalue =/ jsp / template / defaultFooter.jsp/>

< / definition>信息信息亦读目的数信息中信息


Result.jsp

 <％@ taglib prefix =suri =/ struts-tags％> 
< html> 
 
< body> 
档案名称：< s：property value =fileUploadFileName/> 
< br /> 
内容类型：< s：property value =fileUploadContentType/> 
< br /> 
档案：< s：property value =fileUpload/> 
< / body> 
< / html> 
  

解决方案

现在我的问题已经解决。我不得不添加jar（commons fileupload和commons io）不仅仅是我的类路径，而且也是RAD的部署汇编。

I'm trying to upload a file using Struts2 in conjunction with Spring. But, somehow after reaching my action class, my file, filename and file content type are all coming out as null. I tried searching for the problem but for no results. Below is the code for my file upload.

index.jsp:

<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<s:head />
</head>
 <s:actionerror />
<s:form action="uploadAction" method="POST" enctype="multipart/form-data">

<s:file name="fileUpload" label="Choose File" size="40" />

<s:submit value="Upload" name="submit" />

</s:form>

Struts.xml

    <?xml version="1.0" encoding="UTF-8"?>

    <!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
    "http://struts.apache.org/dtds/struts-2.0.dtd">

    <struts>
        <include file="struts-default.xml"/>
        <package name="a" extends="struts-default">

   <action name="resultAction" class="ManagePlanDataFileUploadActionBean"   method="executeFileUploadDemo">

            <interceptor-ref name="fileUpload">
                <param name="maximumSize">10240</param>
                <param name="allowedTypes">text/plain</param>
            </interceptor-ref>                
            <interceptor-ref name="defaultStack" />
    <result name="success">displayResultsJSP</result>

</action>
        </package>
    </struts>

applicationContext-web.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:jee="http://www.springframework.org/schema/jee"
    xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
    http://www.springframework.org/schema/jee
    http://www.springframework.org/schema/jee/spring-jee-2.0.xsd
    http://www.springframework.org/schema/aop
    http://www.springframework.org/schema/aop/spring-aop-2.0.xsd
    http://www.springframework.org/schema/tx
    http://www.springframework.org/schema/tx/spring-tx-2.0.xsd">
    <bean id="ManagePlanDataFileUploadActionBean" scope="prototype"

    class="com.hix.action.planmanagement.ManagePlanDataFileUploadAction">

    </bean>
</beans>

ManagePlanUploadAction

package com.hix.action.planmgmt;

import java.io.File;

import javax.servlet.http.HttpServletRequest;

import org.apache.commons.io.FileUtils;

import com.opensymphony.xwork2.ActionSupport;

public class ManagePlanUploadAction extends ActionSupport{

      private HttpServletRequest request;

      private File fileUpload;
      private String fileUploadContentType;
      private String fileUploadFileName;

       public void setServletRequest(HttpServletRequest paramHttpServletRequest) {
             this.request = paramHttpServletRequest;
       }

       public HttpServletRequest getServletRequest() {
             return request;
       }

        public File getFileUpload() {
            return fileUpload;
        }

        public void setFileUpload(File fileUpload) {
            this.fileUpload = fileUpload;
        }

        public String getFileUploadContentType() {
            return fileUploadContentType;
        }

        public void setFileUploadContentType(String fileUploadContentType) {
            this.fileUploadContentType = fileUploadContentType;
        }

        public String getFileUploadFileName() {
            return fileUploadFileName;
        }

        public void setFileUploadFileName(String fileUploadFileName) {
            this.fileUploadFileName = fileUploadFileName;
        }

        public String executeFileUploadDemo() throws Exception {
            try {
                String filePath = "C:/Myuploads2";
                System.out.println("Server path:" + filePath);
                File fileToCreate = new File(filePath, fileUploadFileName);
                FileUtils.copyFile(fileUpload, fileToCreate);
                } catch(Exception e) {
                    e.printStackTrace();
                    addActionError(e.getMessage());
                    return SUCCESS;
                }       
                    System.out.println("File :" + fileUpload);
                    System.out.println("Filename : " + fileUploadFileName);
                    System.out.println("File type : " + fileUploadContentType);
                return SUCCESS; 
        }
}

tiles-def.xml

<!DOCTYPE tiles-definitions PUBLIC
       "-//Apache Software Foundation//DTD Tiles Configuration 2.0//EN"
       "http://tiles.apache.org/dtds/tiles-config_2_0.dtd">

<tiles-definitions>
<definition name="displayResultsJSP" template="/jsp/planmgmt/Result.jsp">

<put-attribute name="header" value="/jsp/template/defaultHeader.jsp" /> 

<put-attribute name="footer" value="/jsp/template/defaultFooter.jsp" />

</definition>

</tiles-definitions>

Result.jsp

<%@ taglib prefix="s" uri="/struts-tags" %>
<html>

<body>
   File Name : <s:property value="fileUploadFileName"/> 
  <br/>
   Content Type : <s:property value="fileUploadContentType"/> 
  <br/>
   File : <s:property value="fileUpload"/> 
</body>
</html>

解决方案

My issue is resolved now. I had to add the jars (commons fileupload and commons io) not just to my classpath but also to "Deployment Assembly" of RAD.

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