struts2 MVC作为一个比较新的框架，功能非常强大，比之以前的版本1.x 强过太多。

无论是学习还是开发推荐 struts 2， 而且与spring ，Hibernate更容易集成，

还可以方便的与ext 结合做ajax 开发。

不多说，看多文件上传:

环境：JDK 1.6, TOMCAT 5.5.20,

IDE:Myeclipse 6

lib包：struts2-core-2.0.11.1.jar，xwork-2.0.4.jar，freemarker.jar，ognl-2.6.11.jar，

       pull-parser-2.1.10.jar，commons-fileupload.jar 必须的包。

代码：

package org;

import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;
import java.io.*;

public class UploadAction extends ActionSupport {

private static final long serialVersionUID = 1L;

private File[] uploadFile;

private String[] contentType;

private String[] uploadFilename;

private String[] caption;

private String[] hide;

public void setHide(String[] hide) {
   this.hide = hide;
}

public String[] getCaption() {
   return caption;
}

public void setCaption(String[] caption) {
   this.caption = caption;
}

public String[] getContentType() {
   return contentType;
}

public void setUploadFileContentType(String[] contentType) {
   this.contentType = contentType;      // notice:here is the key!! 不要改变命名规范
}

public File[] getUploadFile() {
   return uploadFile;
}

public void setUploadFile(File[] uploadFile) {
   this.uploadFile = uploadFile;
}

public String[] getUploadFilename() {
   return uploadFilename;
}

public void setUploadFileFileName(String[] uploadFilename) {
   this.uploadFilename = uploadFilename;       // notice:here is the key!! 命名约定
}

private static void copy(File src, File dst) {
   try {
    InputStream in = null;
    OutputStream out = null;
    try {
     in = new BufferedInputStream(new FileInputStream(src));
     out = new BufferedOutputStream(new FileOutputStream(dst));
     byte[] buffer = new byte[16 * 1024];
     while (in.read(buffer) > 0) {
      out.write(buffer);
     }
    } finally {
     if (null != in) {
      in.close();
     }
     if (null != out) {
      out.close();
     }
    }
   } catch (Exception e) {
    e.printStackTrace();
   }
}

public String execute() {
   for (String str : hide) {
    System.out.print("---   " + str + " ---\n");
   }
   for (int i = 0; i < this.getUploadFile().length; i++) {
    File imageFile = new File(ServletActionContext.getServletContext()
      .getRealPath("/")
      + "file/" + uploadFilename[i]);
    copy(this.getUploadFile()[i], imageFile);
   }
   return SUCCESS;
}

}

classes/目录下，struts.xml 配置：

<?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>

    <!-- developer mode convenient for Debug -->
    <constant name="struts.devMode" value="true" />
    <constant name="struts.i18n.encoding" value="GBK" />

    <package name="uploadFile" extends="struts-default">

       <action name="myUpload"
          class="org.UploadAction">
          <interceptor-ref
             name="fileUpload">
             <param
                name="allowedTypes">
                image/bmp,image/png,image/gif,image/pjpeg,image/jpg,image/JPG,image/jpeg
             </param>
             <param
                name="maximumSize">
                1024000
             </param>
          </interceptor-ref>
          <interceptor-ref
             name="defaultStack" />
          <result name="input">
             /upload.jsp
          </result>
          <result name="success">
             /showUpload.jsp
          </result>
       </action>
    </package>
</struts>

web.xml配置：

<?xml version="1.0" encoding="gb2312"?>
<!DOCTYPE web-app
PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/j2ee/dtds/web-app_2_3.dtd">
<web-app>

    <display-name>struts2上传文件示例</display-name>

    <filter>
       <filter-name>struts-cleanup</filter-name>
       <filter-class>
          org.apache.struts2.dispatcher.ActionContextCleanUp
       </filter-class>
    </filter>

    <filter>
       <filter-name>struts2</filter-name>
       <filter-class>
          org.apache.struts2.dispatcher.FilterDispatcher
       </filter-class>
    </filter>

 

    <!-- 注意顺序 -->
    <filter-mapping>
       <filter-name>struts-cleanup</filter-name>
       <url-pattern>/*</url-pattern>
    </filter-mapping>


    <filter-mapping>
       <filter-name>struts2</filter-name>
       <url-pattern>/*</url-pattern>
    </filter-mapping>


    <welcome-file-list>
       <welcome-file>upload.jsp</welcome-file>
    </welcome-file-list>
</web-app>

上传页面(ognl 表达式)：upload.jsp

<%@ page language="java" contentType="text/html;charset=gb2312"%>
<%@ taglib prefix="s" uri="/struts-tags"%>

<! DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" >
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>upload file</title>

<%
long i = 88;
String[] str = { "aa", "bb", "cc" };
%>

<script type="text/javascript">  

function addMore()  
{  
   var td = document.getElementById("more");
    
    var ss= document.createElement("span");   
    var br=document.createElement("br");
    var input = document.createElement("input");
    var span= document.createElement("span");   // text zone here
    var text = document.createElement("input");    
    var button = document.createElement("input");  
     
    ss.innerHTML="select file:";
    input.type = "file";  
    input.name = "uploadFile";
    span.innerHTML="say something:";
    text.type="text";
    text.name="caption";
    button.type = "button";  
    button.value = " Remove ";
         button.onclick = function()  
    {  
        td.removeChild(br);          td.removeChild(ss);       td.removeChild(input);  
        td.removeChild(span);      td.removeChild(text);  
        td.removeChild(button);  
    }  
    td.appendChild(br);          td.appendChild(ss);         td.appendChild(input);  
    td.appendChild(span);     td.appendChild(text);
     td.appendChild(button);  
   }
     
   function check(){
   if(document.form1.uploadFile == null ||form1.uploadFile == ""|| form1.caption == null || form1.caption == "")
   {window.alert("请正确输入");
   return false;}
   else{
    return true;}
   }

</script>
</head>

<body>
<s:fielderror />
<s:form action="myUpload" method="post" name="form1"
enctype="multipart/form-data" onsubmit="return check()" theme="simple">
<table border="1">
   <tr>
    <td id="more">select file:<s:file name="uploadFile" /> say
    something: <s:textfield name="caption" label="" /> <input
     type="button" value="add more.." onclick="addMore()" /></td>
   </tr>

   <s:hidden name="hide" value="str"/>
   <tr>

    <td align="center"><s:submit value="submit file" /> <s:reset
     value="reset" /></td>
   </tr>
</table>

</s:form>
</body>
</html>

显示页面：showUpload.jsp

<%@ page language="java" contentType="text/html;charset=GBK"%>
<%@ taglib prefix="s" uri="/struts-tags"%>

<! DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" >
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
   <title>查看上传文件</title>
</head>
<body>

   <center>
    <table border="1">
    <s:iterator value="uploadFilename" status="stat">
     <tr>
      <td>
       <s:property value="%{uploadFilename[#stat.index]}" />
       <br />
      </td>
     </tr>
     <tr>
      <td>
       <s:property value="%{caption[#stat.index]}" />
      </td>
     </tr>
     </s:iterator>
    </table>
   </center>

</body>
</html>