struts2 实现文件的上传
首先将struts2的两个jar包添加到工程目录中：
commons-fileupload-1.2.1.jar
commons-io-1.3.2.jar
除了这两个jar包外，还需要添加struts2所需要的jar包；
上传的界面index.jsp：
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%><%@ taglib prefix="s" uri="/struts-tags"%><%String path = request.getContextPath();String basePath = request.getScheme() + "://"+ request.getServerName() + ":" + request.getServerPort()+ path + "/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><base href="<%=basePath%>"><title>My JSP 'index.jsp' starting page</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"><!--<link rel="stylesheet" type="text/css" href="styles.css"><%=request.getAttribute("name")%><s:property value="tuser.name"/>--></head><body><s:form action="fileUpload.action" method="POST"enctype="multipart/form-data"> 你好${name}，欢迎!当前浏览器的版本为${header["User-Agent"]}<br /> Struts2文件上传： <input type="file" name='myFile' /> <s:textfield name ="caption" label ="Caption" /> <s:submit value="上传"></s:submit></s:form></body></html><?xml version="1.0" encoding="UTF-8"?><web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"><filter><filter-name>struts</filter-name><filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class></filter><filter-mapping><filter-name>struts</filter-name><url-pattern>*.action</url-pattern></filter-mapping> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list></web-app>
<?xml version="1.0" encoding="GBK"?><!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN" "http://struts.apache.org/dtds/struts-2.0.dtd"><struts><package name = "struts2 " namespace="/s" extends="struts-default"><action name = "FirstAction_*" method="{1}"><result name="positive">/yes.jsp</result><result name="negative">/no.jsp</result></action></package> <package name ="fileUploadDemo" extends ="struts-default"> <action name ="fileUpload" class ="Struts2.Action.FileUploadAction"> <interceptor-ref name ="fileUploadStack"/> <result name ="success">/yesFile.jsp </result> </action > </package > </struts>package Struts2.Action;import java.io.BufferedInputStream;import java.io.BufferedOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.util.Date;import org.apache.struts2.ServletActionContext;import com.opensymphony.xwork2.ActionSupport;public class FileUploadAction extends ActionSupport {private static final long serialVersionUID = 572146812454l;private static final int BUFFER_SIZE = 1024 * 1024;private File myFile;private String contentType;private String fileName;private String imageFileName;private String caption;public void setMyFileContentType(String contentType) {this.contentType = contentType;}public void setMyFileFileName(String fileName) {this.fileName = fileName;}public void setMyFile(File myFile) {this.myFile = myFile;}public String getImageFileName() {return imageFileName;}public String getCaption() {return caption;}public void setCaption(String caption) {this.caption = caption;}private static void copy(File src, File dst) {try {InputStream in = null;OutputStream out = null;try {in = new BufferedInputStream(new FileInputStream(src),BUFFER_SIZE);out = new BufferedOutputStream(new FileOutputStream(dst),BUFFER_SIZE);byte[] buffer = new byte[BUFFER_SIZE];while (in.read(buffer) > 0) {out.write(buffer);}} finally {if (null != in) {in.close();}if (null != out) {out.close();}}} catch (Exception e) {e.printStackTrace();}}private static String getExtention(String fileName) {int pos = fileName.lastIndexOf(".");System.out.println("pos::::::" + pos + "====filename.subString():"+ fileName.substring(pos));return fileName.substring(pos);}@Overridepublic String execute(){try {imageFileName = new Date().getTime() + getExtention(fileName);File imageFile = new File(ServletActionContext.getServletContext().getRealPath("/UploadImages")+ "/" + imageFileName);if (!imageFile.exists()) { // 若不存在目标文件，则创建imageFile.getParentFile().mkdirs();imageFile.createNewFile();} else { // 若存在，则删除后重新创建imageFile.delete();imageFile.createNewFile();}copy(myFile, imageFile);} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}return SUCCESS;}}<%@ page language="java" contentType="text/html; charset=utf-8"pageEncoding="utf-8"%><%@ taglib prefix="s" uri="/struts-tags"%><html xmlns="http://www.w3.org/1999/xhtml"><head><title>Struts 2 File Upload</title></head><body><div style="padding: 3px; border: solid 1px #cccccc; text-align: center"><img src='UploadImages/<s:property value="imageFileName"/>'/><br />上传成功：<s:property value="caption" /></div></body></html>