<s:form action="upload2.action" method="post" theme="simple" enctype="multipart/form-data">

<tr>

       <td id="more">

             选择上传文件:<s:file name="file"></s:file><br>

             <s:submit type="button" value="submit"/>

         </td>

  </tr>

</s:form>

 <package name="struts2" extends="struts-default">

    <action name="upload2"class="com.hloytax.wg.upload.UploadAction1">

           <result name="success">/success.jsp</result>

            <interceptor-ref name="fileUpload">

                 <param name="maximumSize">409600</param> //上传文件大小设置

                // <!--allowedTypes (可选) - 以逗号分割的contentType类型列表(例如text/html), <param name="contentType"> application/txt; </param>
            <param name="allowedTypes">

                 </param>

             </interceptor-ref>

             <interceptor-ref name="defaultStack"></interceptor-ref>

        </action>

   </package>

public class UploadAction1 extends ActionSupport {

    /**

     *

     */

    private static final long serialVersionUID = 1L;

    private File file;

      //文件名称

    private String fileFileName;  

    //文件类型

    private String fileContentType;

    //注意：文件名称和文件类型的名称前缀必须相同，

    省略get set 方法 

    @Override

    public String execute() throws Exception{     

        //获取需要上传文件的文件路径

        File uploadFile=new File(ServletActionContext.getServletContext().getRealPath("uploadFile"));

        //判断文件是否上传，如果上传的话将会创建该目录

        if(!uploadFile.exists()){

            uploadFile.mkdir(); //创建该目录

        }  

        /*//第一种文件上传的方法

        //声明文件输入流，为输入流指定文件路径

        FileInputStream input=new FileInputStream(file);

        //获取输出流，获取文件的文件地址及名称

        FileOutputStream out=new FileOutputStream(uploadFile + "\\" +fileFileName);  

        try{

            byte[] b=new byte[1024];//每次写入的大小

            int i=0;

            while((i=input.read(b))>0){

                out.write(b,0,i);

            }

        }catch(Exception e){

            e.printStackTrace();

        }finally{

            input.close();

            out.close();

        }

          */

        //第二种文件上传的方法

        //FileUtils.copyFile(file,new File(uploadFile+"\\"+fileFileName));

       // FileUtils.copyFile(file,new File(uploadFile,fileFileName));

       // System.out.println(uploadFile);

        //第三种方法

      BufferedReader bReader=new BufferedReader(new InputStreamReader(new FileInputStream(file)));

      BufferedWriter bWriter=new BufferedWriter(new OutputStreamWriter(new FileOutputStream(uploadFile+"\\"+fileFileName)));

      System.out.println(uploadFile);

      try{

          char[] str=new char[1024];

          int i=0;

          while((i=bReader.read(str))>0){

              bWriter.write(str,0,i);

          }

      }catch(Exception e){

          e.printStackTrace();

      }finally{

         bReader.close();

          bWriter.close();

          uploadFile.delete();

      }  

        return SUCCESS;

    }
  

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

<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xmlns="http://java.sun.com/xml/ns/javaee"

    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"

    id="WebApp_ID" version="2.5">

    <filter>

        <filter-name>struts2</filter-name>

        <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>

    </filter>

    <filter-mapping>

        <filter-name>struts2</filter-name>

        <url-pattern>/*</url-pattern>

    </filter-mapping>

</web-app>

private List<File> file;

private List<String> fileContentType;

private List<String> fileFileName;
private String savePath;

省略get  set 方法   上传方法  参照单文件上传
@Override
    public String execute() throws Exception {
        List<File> files= getFile();
        if (files !=null) {
                for (int i = 0; i < files.size(); i++) {
                    FileOutputStream fos = new FileOutputStream(getSavePath() + "\\" + getFileFileName().get(i));
                    //建立上传文件的输入流
                    System.out.println(getSavePath());
                    FileInputStream fis = new FileInputStream(files.get(i));

        byte[] buffer = new byte[1024];
        int len = 0;
        while ((len = fis.read(buffer)) > 0) {
             fos.write(buffer, 0, len);
         }
         fis.close();
         fos.close();
     }
 }
      return SUCCESS;
        
            }

    /**
     * 返回上传文件保存的位置
     * 
     * @return
     * @throws Exception
     */
    public String getSavePath() throws Exception {
        return ServletActionContext.getServletContext().getRealPath(savePath);
    }
    public void setSavePath(String savePath) {
        this.savePath = savePath;
    }