一、前言
由于Struts2框架对上传组件进行了封装，使得文件上传的实现简单。
在Struts2框架中提供对commons-fileupload组件的支持，并且默认使用该组件实现文件上传。因此，为了实现文件上传功能，我们需要在项目中包含如下两个jar文件：
commons-fileupload-x.x.x.jar、commons-io-x.x.x.jar 注意：jar文件版本取决于当前工程使用的Struts2的版本。
二、实现文件上传
1）上传页面的准备
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <%@taglib uri="/struts-tags" prefix="s"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>文件上传</title> </head> <body> <s:form action="upload" enctype="multipart/form-data" method="post"> <s:textfield name="title" label="标题"/> <s:file name="upload" label="选择文件"/> <s:submit name="submit" value="文件上传"/> </s:form> </body> </html>
2）开发实现文件上传的Action
package cn.happy.action; import java.io.FileInputStream; import java.io.FileOutputStream; import org.apache.struts2.ServletActionContext; import com.opensymphony.xwork2.Action; import com.opensymphony.xwork2.ActionSupport; @SuppressWarnings("serial") public class UploadAction extends ActionSupport implements Action{ //封装上传文件属性 private String upload; //封装上传文件的类型 private String uploadContentType; //封装上传文件的名称 private String uploadFileName; //获取文件上传路径 private String savePath; @Override public String execute() throws Exception{ byte[] buffer=new byte[1024]; //读取文件 FileInputStream fis=new FileInputStream(getUpload()); //保存文件，并设置保存目录的路径 FileOutputStream fos=new FileOutputStream(getSavePath()+"\"+this.getUploadFileName()); int length=fis.read(buffer); while(length>0){ //每次写入长度的内容 fos.write(buffer,0,length); length=fis.read(buffer); } fis.close(); fos.flush(); fos.close(); return SUCCESS; } //获取上传文件的保存路径 //通过读取存放目录获取的保存路径 public String getSavePath() { return ServletActionContext.getServletContext().getRealPath(savePath); } public void setSavePath(String savePath) { this.savePath = savePath; } public String getUpload() { return upload; } public void setUpload(String upload) { this.upload = upload; } public String getUploadContentType() { return uploadContentType; } public void setUploadContentType(String uploadContentType) { this.uploadContentType = uploadContentType; } public String getUploadFileName() { return uploadFileName; } public void setUploadFileName(String uploadFileName) { this.uploadFileName = uploadFileName; } }
3）Struts.xml配置
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN" "http://struts.apache.org/dtds/struts-2.3.dtd"> <struts > <!-- <constant name="struts.devMode" value="true" /> --> <constant name="struts.devMode" value="false" /> <!--创建一个default包，继承自Struts2的struts-default包 --> <package name="default" namespace="" extends="struts-default"> <action name="upload" class="cn.happy.action.UploadAction"> <!-- 通过param参数设置保存目录路径 --> <param name="savePath">/upload</param> <result name="success">upload_success.jsp</result> </action> </package> </struts>
4）在成功页面
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <%@taglib uri="/struts-tags" prefix="s"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>文件上传成功</title> </head> <body> 您所上传的文件是：<s:property value="uploadFileName"/> 文件类型：<s:property value="uploadContentType"/> 文件路径：<s:property value="savePath"/> </body> </html>
三、实现文件下载
1）下载页面准备
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <%@taglib uri="/struts-tags" prefix="s"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>文件下载</title> </head> <body> <a href="download?fileName=007.jpg">点击此处下载文档</a> </body> </html>
2）开始实现文件下载的Action
package cn.happy.action; import java.io.BufferedInputStream; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.InputStream; import org.apache.struts2.ServletActionContext; import com.opensymphony.xwork2.ActionSupport; @SuppressWarnings("serial") public class FileDownAction extends ActionSupport { //读取下载的文件目录 private String inputPath; //下载文件的文件名 private String fileName; //读取下载文件的输入流 @SuppressWarnings("unused") private InputStream inputStream; //下载的文件类型 private String conetntType; //创建inputStream输入流 @Override public String execute() throws Exception { return SUCCESS; } public InputStream getInputStream() throws FileNotFoundException { String path=ServletActionContext.getServletContext().getRealPath(inputPath); return new BufferedInputStream(new FileInputStream(path+"\"+fileName)); } public void setInputStream(InputStream inputStream) { this.inputStream = inputStream; } public String getInputPath() { return inputPath; } public void setInputPath(String inputPath) { this.inputPath = inputPath; } public String getFileName() { return fileName; } public void setFileName(String fileName) { this.fileName = fileName; } public String getConetntType() { return conetntType; } public void setConetntType(String conetntType) { this.conetntType = conetntType; } }
3）Struts.xml配置
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN" "http://struts.apache.org/dtds/struts-2.3.dtd"> <struts > <!-- <constant name="struts.devMode" value="true" /> --> <constant name="struts.devMode" value="false" /> <!--创建一个default包，继承自Struts2的struts-default包 --> <package name="default" namespace="" extends="struts-default"> <action name="upload" class="cn.happy.action.UploadAction"> <!-- 文件下载 --> <action name="download" class="cn.happy.action.FileDownAction"> <param name="inputPath">/upload</param> <result name="success" type="stream"> <param name="conetntType">application/octet-stream</param> <!-- <param name="conetntType">image/gif</param> --> <param name="inputName">inputStream</param> <param name="contentDisposition">attachement;filename="${fileName}"</param> <param name="bufferSize">4096</param> </result> </action> </package> </struts>
注意！！！！
contentType对应的文件类型
| 文件类型 | contentType设置 |
| Word | application/msword |
| Execl | Application/vnd.ms-excel |
| PPT | Application/vnd.ms-powerpoint |
| 图片 | image/gif、image/bmp、image/jpeg |
| 文本文件 | text/plain |
| HTML网页 | text/html |
| 可执行文件 | application/octet-stream |