Servlet：htm+javascript+css+servlet （ajax）实现上传（能显示进度条）

本示例需要commons-fileupload-1.3.jar和commons-io-2.4.jar的支持，新手请参阅无进度条的上传

http://blog.csdn.net/tabactivity/article/details/11180631

确认您的环境配置成功后，下面开始编码：

src/UploadStatus.java ，数据模型类

package com.xieyuan;

public class UploadStatus {

	private long bytesRead;

	private long contentLength;

	private int items;

	private long startTime = System.currentTimeMillis();

	public long getBytesRead() {
		return bytesRead;
	}

	public void setBytesRead(long bytesRead) {
		this.bytesRead = bytesRead;
	}

	public long getContentLength() {
		return contentLength;
	}

	public void setContentLength(long contentLength) {
		this.contentLength = contentLength;
	}

	public int getItems() {
		return items;
	}

	public void setItems(int items) {
		this.items = items;
	}

	public long getStartTime() {
		return startTime;
	}

	public void setStartTime(long startTime) {
		this.startTime = startTime;
	}

}

src/UploadListener.java，继承自ProgressListener，当使用commons_uploadfile组件上传时，调用组件类的方法可添加上传监听，组件就会不断调用UploadListener的update方法

package com.xieyuan;

import org.apache.commons.fileupload.ProgressListener;

public class UploadListener implements ProgressListener {

	private UploadStatus status;

	public UploadListener(UploadStatus status) {
		this.status = status;
	}

	public void update(long bytesRead, long contentLength, int items) {
		status.setBytesRead(bytesRead);
		status.setContentLength(contentLength);
		status.setItems(items);
		
	}
}

src/UploadServlet.java，该类doPost方法用于处理上传，index.jsp后台会使用XmlHttpRequest调用本Servlet的doGet方法，从session中获取最新的上传数据情况

package com.xieyuan;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.sound.sampled.AudioFormat.Encoding;

import org.apache.commons.fileupload.DiskFileUpload;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;


public class UploadServlet extends HttpServlet {

    //定义临时文件盒上传文件的存储路径
    private File uploadTemp=null;
    private File uploadPath=null;
    
    /**
     * Constructor of the object.
     */
    public UploadServlet() {
        super();
    }

    /**
     * Destruction of the servlet. <br>
     */
    public void destroy() {
        super.destroy(); // Just puts "destroy" string in log
        // Put your code here
    }


    /**
     * The doGet method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to get.
     * 
     * @param request the request send by the client to the server
     * @param response the response send by the server to the client
     * @throws ServletException if an error occurred
     * @throws IOException if an error occurred
     */
    public void doGet(HttpServletRequest request, HttpServletResponse response)
           &n