SpringMVC实现文件上传进度条

  文件上传一般都是基于commons-fileupload组件来实现，SpringMVC的文件上传功能也是在commons-fileupload组件提供的功能上面做了一些包装功能.

  Commons-fileupload组件自带了文件上传进度的监听器，类FileUploadBase提供了它的set方法：

 

public voidsetprogressListener(ProgressListener pListener)

        {

listener= pListener;

        }

ProgressListener是一个接口，我们需要自己实现它的update方法，参数pBytesRead表示已经上传到服务器的字节数，pContentLength表示所有文件的总大小，pItems表示第几个文件：

       protected FileUploadnewFileUpload(FileItemFactory fileItemFactory)

{

return newServletFileUpload(fileItemFactory);

}

我们要做的就是实现ProgressListener类

public classFileUploadListener implements ProgressListener {

private longnum100Ks = 0;

private longtheBytesRead = 0;

private longtheContentLength = -1;

private intwhichItem = 0;

private intpercentDone = 0;

private booleancontentLengthKnown = false;

public voidupdate(long bytesRead, long contentLength, int items){

if(contentLength > -1) {

contentLengthKnown = true;

}

theBytesRead =bytesRead;

theContentLength= contentLength;

whichItem =items;

long nowNum100Ks= bytesRead / 100000;

if (nowNum100Ks> num100Ks) {

num100Ks =nowNum100Ks;

if(contentLengthKnown) {

percentDone =(int) Math.round(100.00 * bytesRead / contentLength);

}

}

}

public int getPercentDone(){

return percentDone;

}

}

SpringMVC没有实现监听器，所以如果要监听的话得自己扩展CommonsMultipartResolver类，在newFileUpload里面加入代码设置自己实现的监听器：

public classCommonsMultipartResolverExt extends CommonsMultipartResolver{

privateHttpServletRequest request;

@Override

protected FileUpload newFileUpload(FileItemFactoryfileItemFactory)

{

ServletFileUpload upload = newServletFileUpload(fileItemFactory); 

upload.setSizeMax(-1); 

if(request!=null)

{

///System.out.println("注入监听");

FileUploadListener uploadProgressListener = newFileUploadListener();

upload.setProgressListener(uploadProgressListener);

HttpSessionsession = request.getSession();

session.setAttribute("uploadProgressListener",uploadProgressListener);

}

returnupload;

}

@Override

publicMultipartHttpServletRequest resolveMultipart(HttpServletRequestrequest) throws MultipartException {

     this.request=request;//获取到request,要用到session

      returnsuper.resolveMultipart(request);

 }

}

建一个servlet用ajax去取进度就可以了

public classProgressServlet extends HttpServlet {

private staticfinal long serialVersionUID = 1L;

public voiddoGet(HttpServletRequest request, HttpServletResponse response)throws IOException {

doPost(request,response);

}

public voiddoPost(HttpServletRequest request, HttpServletResponse response)throws IOException {

response.setContentType("text/html");

response.setHeader("Cache-Control","no-cache");

PrintWriter out= response.getWriter();

HttpSessionsession = request.getSession(true);

if (session ==null) {

out.println("Sorry, session is null"); // justto be safe

return;

}

FileUploadListener uploadProgressListener =(FileUploadListener)session.getAttribute("uploadProgressListener");

if(uploadProgressListener == null) {

out.println("Progress listener isnull");

return;

}

intret=uploadProgressListener.getPercentDone();

System.out.println("new->:"+String.valueOf(ret));

out.println(ret);

}

}

1. 在Spring的配置文件中添加 Xml代码  
2. id="multipartResolver"class="net.gkyh.filter.CommonsMultipartResolverExt">  
3. name="defaultEncoding" value="UTF-8" />  

SpringController

@RequestMapping(value="/AppUpload.action",method=RequestMethod.POST)

publicModelAndView Upload(HttpServletRequest request,HttpServletResponseresponse,

@RequestParam("flag")String flag,ModelMapmodelMap){

try

{

Stringpath=request.getSession().getServletContext().getRealPath("/");

path=path.substring(0,path.length()-1);

 intp=path.lastIndexOf("\");

path=path.substring(0,p);

path=path.replace("\","/");

StringfolderPath=path+"/ftp/upload/";

 

MultipartHttpServletRequestmultipartRequest = (MultipartHttpServletRequest) request; 

          CommonsMultipartFile file =(CommonsMultipartFile)multipartRequest.getFile("filedata");

 // filedata 是表单的名字

                

InputStreamstream = file.getInputStream();  

String fileName= file.getOriginalFilename(); 

//System.out.println(fileName);

         StringfileNameFull = folderPath +fileName; 

        OutputStream bos = new FileOutputStream(fileNameFull); 

         intbytesRead = 0;  

         byte[]buffer = new byte[8192];  

         while((bytesRead = stream.read(buffer, 0, 8192)) != -1) { 

            bos.write(buffer, 0, bytesRead); 

         } 

 

        bos.close();  

        stream.close();  

  modelMap.put("msg","添加成功"); 

}

catch(Exceptione) {

e.printStackTrace();

}

return newModelAndView("/appupload",modelMap);

}

jsp页面

 <SCRIPT src="../js/jquery-1.3.2.min.js"type="text/javascript"></SCRIPT>

<SCRIPTtype=text/javascript>

functiondoProgressLoop(prog, max, counter) { 

   var x =document.getElementByIdx_x_x('progress-content').innerHTML;

   var y = parseInt(x);

   if (!isNaN(y)) {

   prog = y;

   }

counter =counter + 1;

   if (prog < 100) {

   setTimeout("getProgress()", 1000);

   setTimeout("doProgressLoop(" + prog + "," + max+ "," + counter + ")", 1500);

document.getElementByIdx_x_x('progressBarText').innerHTML= 'upload in progress: ' + prog + '%';

document.getElementByIdx_x_x('progressBarBoxContent').style.width= parseInt(prog) + '%';

   }

}

functiongetProgress() {

$.ajax({

       type:"post",

       dataType:"string",

       url:"ProgressServlet.do",

       data:"",

       success:function (data) {        

         document.getElementByIdx_x_x('progress-content').innerHTML=data;

      },

       error:function (err) {

        document.getElementByIdx_x_x('progressBarText').innerHTML="Errorretrieving progress";

      }

   });

}

  

functionfSubmit()

{

var button =window.document.getElementByIdx_x_x("submitButton");

button.disabled =true;

var max =100;

var prog =0;

var counter= 0;

document.getElementByIdx_x_x('progressBar').style.display= 'block';

document.getElementByIdx_x_x('progressBarText').innerHTML= 'upload in progress: 0%';

getProgress();

doProgressLoop(prog, max,counter);

document.getElementByIdx_x_x("form1").submit();

}

</SCRIPT>

<formname="form1" id="form1" action="AppLoad.action" method="post"enctype="multipart/form-data">

<span>选择文件</span>

<divstyle="padding-bottom:5px;">

<inputtype="file" size="48" name="filedata"id='filedata'>

</div>

<divid="progressBar" style="display:none;"> 

<divid="theMeter"> 

<divid="progressBarText"></div> 

<divid="progressBarBox"style="color:Silver;border-width:1px;border-style:Solid;width:300px;TEXT-ALIGN:left"> 

<divid="progressBarBoxContent" style="background-color:#3366FF;height:15px;width:0%;TEXT-ALIGN:left"></div> 

</div>

<divid="progress-content" style="display:none;"></div>

</div> 

</div>

<INPUT id='submitButton'  tabIndex=3type=button value="提交" onclick='fSubmit();'>

</form>

以下链接是servlet上传文件进度实例,本文使用了部分内容

http://www.avajava.com/tutorials/lessons/how-do-i-display-file-upload-progress-using-the-dojo-progressbar.html?page=1