首先Spring是一个非常成熟的J2EE框架，其非入侵式的架构为系统的集成和扩展提供了最大的可能。所以Spring MVC下实现进度监听非常容易，甚至不需要改以前的上传业务代码，具体实现分三个步骤：
1、接管CommonsMultipartResolver，重写针对文件上传的请求。
2、在第一步中写入监听，以获取上传进度。
3、修改上传部分的配置文件。
具体见代码

1、CommonsMultipartResolver代码

package com.van.utils.upload.handle;import java.util.List;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpSession;import org.apache.commons.fileupload.FileItem;import org.apache.commons.fileupload.FileItemFactory;import org.apache.commons.fileupload.FileUpload;import org.apache.commons.fileupload.FileUploadBase;import org.apache.commons.fileupload.FileUploadException;import org.apache.commons.fileupload.servlet.ServletFileUpload;import org.springframework.web.multipart.MaxUploadSizeExceededException;import org.springframework.web.multipart.MultipartException;import org.springframework.web.multipart.MultipartHttpServletRequest;import org.springframework.web.multipart.commons.CommonsMultipartResolver;import com.van.utils.upload.listener.PJProgressListener;/** * 重写CommonsMultipartResolver以监听文件上传进度 * @author Van * @date 2012-12-12 */public class PJCommonsMultipartResolver extends CommonsMultipartResolver {    private HttpServletRequest request;    protected FileUpload newFileUpload(FileItemFactory fileItemFactory) {        ServletFileUpload upload = new ServletFileUpload(fileItemFactory);        upload.setSizeMax(-1);        if (request != null) {            HttpSession session = request.getSession();            PJProgressListener uploadProgressListener = new PJProgressListener(session);            upload.setProgressListener(uploadProgressListener);        }        return upload;    }    public MultipartHttpServletRequest resolveMultipart(            HttpServletRequest request) throws MultipartException {        this.request = request;// 获取到request,要用到session        return super.resolveMultipart(request);    }     @SuppressWarnings("unchecked")    @Override    public MultipartParsingResult parseRequest(HttpServletRequest request) throws MultipartException {         HttpSession session = request.getSession();        String encoding = "utf-8";        FileUpload fileUpload = prepareFileUpload(encoding);        PJProgressListener uploadProgressListener = new PJProgressListener(session);        fileUpload.setProgressListener(uploadProgressListener);        try {            List<FileItem> fileItems = ((ServletFileUpload) fileUpload).parseRequest(request);            return parseFileItems(fileItems, encoding);        }        catch (FileUploadBase.SizeLimitExceededException ex) {            throw new MaxUploadSizeExceededException(fileUpload.getSizeMax(), ex);        }        catch (FileUploadException ex) {            throw new MultipartException("Could not parse multipart servlet request", ex);        }    }}

PJProgressListener 代码：

package com.van.utils.upload.listener;import javax.servlet.http.HttpSession;import org.apache.commons.fileupload.ProgressListener;import com.van.utils.upload.entity.ProgressEntity;public class PJProgressListener implements ProgressListener{    private HttpSession session;    public PJProgressListener() {    }    public PJProgressListener(HttpSession _session) {        session=_session;        ProgressEntity ps = new ProgressEntity();        session.setAttribute("upload_ps", ps);    }    public void update(long pBytesRead, long pContentLength, int pItems) {        ProgressEntity ps = (ProgressEntity) session.getAttribute("upload_ps");        ps.setpBytesRead(pBytesRead);        ps.setpContentLength(pContentLength);        ps.setpItems(pItems);        //更新        session.setAttribute("upload_ps", ps);    }}

上传进度信息记录实体类：

package com.van.utils.upload.entity;/** * 文件上传进度信息 * @author Van * */public class ProgressEntity {    private long pBytesRead = 0L;    private long pContentLength = 0L;    private int pItems;    public long getpBytesRead() {        return pBytesRead;    }    public void setpBytesRead(long pBytesRead) {        this.pBytesRead = pBytesRead;    }    public long getpContentLength() {        return pContentLength;    }    public void setpContentLength(long pContentLength) {        this.pContentLength = pContentLength;    }    public int getpItems() {        return pItems;    }    public void setpItems(int pItems) {        this.pItems = pItems;    }    @Override    public String toString() {        return "ProgressEntity [pBytesRead=" + pBytesRead + ", pContentLength="                + pContentLength + ", pItems=" + pItems + "]";    }}

配置文件部分修改：

<!-- 文件上传支持  -->    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">        <property name="defaultEncoding" value="UTF-8" />        <!-- 内存缓存1M -->        <property name="maxInMemorySize" value="1000000"></property>        <!-- 最大2GB -->        <property name="maxUploadSize" value="2000000000" ></property>    </bean>

将org.springframework.web.multipart.commons.CommonsMultipartResolver替换成：com.van.utils.upload.handle.PJCommonsMultipartResolver