struts实现上传下载

最新推荐文章于 2024-06-29 22:48:48 发布

原创最新推荐文章于 2024-06-29 22:48:48 发布 · 110 阅读

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文章标签：

#Struts #Apache #Servlet #JSP #Bean

本文详细介绍了如何利用Struts框架实现文件上传功能，包括上传页面的实现代码、Action类处理上传请求、下载和打开上传文件的过程。文章还涉及了Struts对multipart/form-data编码数据的处理方式以及如何在Session中保存上传文件的相关信息。

上传页面的实现代码如下
upload.jsp
<%@ page language="java" pageEncoding="UTF-8"%>

<%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean" %>
<%@ taglib uri="http://struts.apache.org/tags-html" prefix="html" %>
<%@ taglib uri="http://struts.apache.org/tags-logic" prefix="logic" %>
<%@ taglib uri="http://struts.apache.org/tags-tiles" prefix="tiles" %>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html:html lang="true">
<head>
<html:base />

<title>upload.jsp</title>

<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">


</head>

<body>
<html:form action="" method="post" enctype="multipart/form-data">
<table>
<tr>
<td align="center" colspan="2">
<font size="4">Please Enter the Following Details</font>
</td>
</tr>
<tr>
<td align="left" colspan="2">
<font color="red"><htm:errors /></font>
</td>
</tr>
<tr>
<td align="right">
FileName
</td>
<td align="left">
<html:file property="theFile"></html:file>
</td>
</tr>
<tr>
<td align="center" colspan="2">
<html:submit>Upload File</html:submit>
</td>
</tr>
</table>
</html:form>
</body>
</html:html>

其中struts通过表单实现页面的上传时，需要在form表单把enctype="multipart/form-data",使用了这个属性后，HttpServletRequest对象的getParameter()方法就无法直接得到用户所提交的其他数据。好在struts对这种格式编码的数据进行了处理，使得用户提交的数据仍然可以被直接设置成actionForm种对应的值。

ActionForm：

package ActionForm;

import org.apache.struts.action.ActionForm;
import org.apache.struts.upload.FormFile;

public class UploadForm extends ActionForm {

private FormFile theFile;

public FormFile getTheFile() {
return theFile;
}

public void setTheFile(FormFile theFile) {
this.theFile = theFile;
}
}

UploadAction文件

package com.xpjjy.struts;

import java.io.File;
import java.io.FileOutputStream;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.upload.FormFile;

import ActionForm.UploadForm;

public class UploadAction extends Action {

public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception{
UploadForm uploadForm = (UploadForm) form;

FormFile file = uploadForm.getTheFile();
String contentType = file.getContentType();
String fileName = file.getFileName();
int fileSize = file.getFileSize();
byte[] fileData = file.getFileData();

System.out.println("Contentype: "+ contentType);
System.out.println("FileName: " + fileName);
System.out.println("File Size "+ fileSize);

FileOutputStream out = new FileOutputStream(new File("D:\\"+fileName));
out.write(fileData);
out.close();

HttpSession session = request.getSession();
session.setAttribute("contentType", contentType);
session.setAttribute("fileName", fileName);
session.setAttribute("fileSize", Integer.valueOf(fileSize));

return mapping.findForward("download");
}
}

httpSession的相关资料空间有

download.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib uri="http://struts.apache.org/tags-html" prefix="html" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Download and Open the File</title>
</head>
<body>
<html:link action="/download">Download</html:link>
<br>
<html:link action="/open">Open</html:link>
</body>
</html>

DownloadFileAction

package com.xpjjy.struts;

import java.io.File;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.actions.DownloadAction;

public class DownloadFileAction extends DownloadAction {

protected StreamInfo getStreamInfo(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response) throws Exception {
HttpSession session = request.getSession();
String contentType = (String)session.getAttribute("contentType");
String fileName = (String)session.getAttribute("fileName");

response.setHeader("content-disposition", "attachment; filename="+fileName);
File file = new File("D:\\"+ fileName);
return new FileStreamInfo(contentType,file);
}

}

Strut 的配置文件 struts-config.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts-config PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 1.3//EN" "http://struts.apache.org/dtds/struts-config_1_3.dtd">

<struts-config>
<form-beans>
<form-bean name="uploadForm" type="ActionForm.UploadForm" />
</form-beans>
<global-exceptions />
<global-forwards />
<action-mappings >
<action path="/OutputXMLAction"
type="com.xpjjy.struts.OutputXMLAction"
scope="request"
>
<forward name="success" path="/index.jsp" />
</action>
<action
attribute="uploadForm"
input="/upload.jsp"
name="uploadForm"
path="/upload"
scope="request"
type="com.xpjjy.struts.UploadAction"
>
<forward name="download" path="/download.jsp" />
</action>

<action path="/download"
type="com.xpjjy.struts.DownloadFileAction"
scope="request"
>
</action>

</action-mappings>

<message-resources parameter="com.xpjjy.struts.ApplicationResources" />
</struts-config>