Struts2上传文件

JSP页面:
<form action="uploadPhoto.action" method="post" enctype="multipart/form-data">
    <table>
    <tr>
    <td><input type="file" name="photoFile"></td>
    <td><input type="submit" value="上传"></td>
    </tr>
    </table>
</form>

struts.xml配置文件:
<action name="uploadPhoto" class="com.fy.action.UploadPhotoAction">
    <interceptor-ref name ="fileUploadStack"/>
    	<result name="success" type="redirect-action">
    	    <param name="actionName">photo</param>
    	</result>
</action>

Action文件:
private File photoFile;
	private String photoFileFileName;
	private String photoFileContentType;
	
	private PhotoDAO photoDAO;
	
	private final int BUFFER_SIZE = 16 * 1024 ;
	
	public String execute()
	{
		HttpServletRequest request=ServletActionContext.getRequest();

		File dst=new File(ServletActionContext.getServletContext().getRealPath("\\photo")+"\\"+photoFileFileName);
		copy(photoFile,dst);
		
		return "success";
	}
	
	private 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];
               int len;
               while((len=in.read(buffer))>0) 
               {
            	   out.write(buffer,0,len);
            	   out.flush();
               } 
           }
           finally 
           {
               if(null!=in) 
               {
                  in.close();
               } 
               if(null!=out)
               {
                  out.close();
               } 
           } 
       }
       catch(Exception e) 
       {
           e.printStackTrace();
       } 
   }