文件上传---动作条

  利用Apache commons fileupload上传文件,直接显示其完成的进度条。----示例代码源自《JAVA WEB王者归来》

  1 首先要显示动作条要利用Ajax的异步请求,使得在没有完成时,不会刷新本页,而是局部的刷新。如果没有指定form的定向页面,默认是刷新本页,正常我们提交一个form刷新本页,在没有完成请求前是显示空白的网页,这里我们指定他刷新一个不显示的区域,就要用到form的属性target。

<iframe name=uploadiframe width=0 height=0></iframe>
    <form action="servlet/ProgressUploadServlet" method="post" enctype="multipart/form-data"
        target="uploadiframe" onsubmit="showStatus();">
        <input type="file" name="file1" style="width:350px;"/><br/>
        <input type="file" name="file2" style="width:350px;"/><br/>
        <input type="file" name="file3" style="width:350px;"/><br/>
        <input type="submit" value="submit" id="btnSubmit"/>    
    </form> 

2 我们创建一个status的bean,用来保存一些状态信息,比如名字,读取的长度,读取的字节大小,时间等等。

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;
    }
}

3 创建一个监听器实时的获取状态信息

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);
    }
}

4 form表单用pos方法提交后,在doPost里面获取状态信息,保存到session中。在本页面,在自动用get方法读取session中的信息,返回给网页,网页动态的进行数据的显示。

  doPost

UploadStatus status = new UploadStatus();
        UploadListener listener = new UploadListener(status);
        request.getSession(true).setAttribute("uploadStatus",status);
        
        ServletFileUpload upload = new ServletFileUpload(new DiskFileItemFactory());
        
        upload.setProgressListener(listener);

  doGet

long startTime = status.getStartTime();
        long currentTime = System.currentTimeMillis();
        long time = (currentTime - startTime)/1000 + 1;
        
        double velocity = ((double)status.getBytesRead())/(double)time;
        
        double totalTime = status.getContentLength()/velocity;
        
        double timeLeft = totalTime - time;
        
        int percent = (int)(100*(double)status.getBytesRead()/(double)status.getContentLength());
        
        double length = ((double)status.getBytesRead())/1024/1024;
        
        double totalLength = ((double)status.getContentLength())/1024/1024;
        
        String value = percent +"||" + length + "||" +totalLength+"||"+
                        velocity+"||"+time+"||"+totalTime+"||"+timeLeft+"||"+status.getItems();
        
        response.getWriter().println(value);

js

<script type="text/javascript">
        var finished = true;
        function $(obj){
            return document.getElementById(obj);
        }
        function showStatus(){
            finished = false;
            $('status').style.display = 'block';
            $('progressBarItem').style.width = '1%';
            $('btnSubmit').disabled = true;
            setTimeout("requestStatus()",1000);
        }
        function requestStatus(){
            if(finished) return;
            var req = createRequest();
            req.open("GET","servlet/ProgressUploadServlet");
            req.onreadystatechange = function(){callback(req);}
            
            req.send(null);
            setTimeout("requestStatus()",1000);
        }
        function createRequest(){
            if(window.XMLHttpRequest){
                return new XMLHttpRequest();
            }else{
                try{
                    return new ActiveXObject("Msxml2.XMLHTTP");
                }catch(e){
                    return new ActiveXObject("Microsoft.XMLHTTP");
                }
            }
            return null;
        }
        function callback(req){
            if(req.readyState == 4){
                if(req.status != 200){
                    debug("error! req.status:"+req.status+"");
                    return ;
                }
                debug("status.jsp return value:"+req.responseText);
                var ss = req.responseText.split("||");
                $('progressBarItem').style.width = ''+ss[0]+'%';
                $('statusInfo').innerHTML = 'end of total:'+ss[0] +'%<br/>'+
                'sucess of numbers:'+ss[1]+'<br/>'+
                'length of file:'+ss[2]+'<br/>'+
                'velocity of trans:'+ss[3]+'<br/>'+
                'the time used:'+ss[4]+'<br/>'+
                'total time:'+ss[5]+'<br/>'+
                'other time:'+ss[6]+'<br/>'+
                'which is translating:'+ss[7];
                
                if(ss[1] == ss[2]){
                    finished = true;
                    $('statusInfo').innerHTML += "<br/><br/><br/>have done!";
                    $('btnSubmit').disabled = false;
                
                }
            }
        }
        function debug(obj){
            var div = document.createElement("DIV");
            div.innerHTML = "[debug]:"+obj;
            document.body.appendChild(div);
        }
    </script>

全部代码:

progressFileupload.jsp

<%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    
    <title>My JSP 'progressFileupload.jsp' starting page</title>
    
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">    
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
    <style type="text/css">
        #progressBar {width:400px;height:12px;background:#FFFFFF;border:1px solid #000000;padding:1px}
        #progressBarItem{width:30%;height:100%;background:#FF0000;}
    </style>
  </head>
  
  <body>
      <iframe name=uploadiframe width=0 height=0></iframe>
    <form action="servlet/ProgressUploadServlet" method="post" enctype="multipart/form-data"
        target="uploadiframe" onsubmit="showStatus();">
        <input type="file" name="file1" style="width:350px;"/><br/>
        <input type="file" name="file2" style="width:350px;"/><br/>
        <input type="file" name="file3" style="width:350px;"/><br/>
        <input type="submit" value="submit" id="btnSubmit"/>    
    </form> 
    <div id="status" style="display:none;">
    uploadbar:
        <div id="progressBar"><div id="progressBarItem"></div></div>
        <div id="statusInfo"></div>
    </div>
    <script type="text/javascript">
        var finished = true;
        function $(obj){
            return document.getElementById(obj);
        }
        function showStatus(){
            finished = false;
            $('status').style.display = 'block';
            $('progressBarItem').style.width = '1%';
            $('btnSubmit').disabled = true;
            setTimeout("requestStatus()",1000);
        }
        function requestStatus(){
            if(finished) return;
            var req = createRequest();
            req.open("GET","servlet/ProgressUploadServlet");
            req.onreadystatechange = function(){callback(req);}
            
            req.send(null);
            setTimeout("requestStatus()",1000);
        }
        function createRequest(){
            if(window.XMLHttpRequest){
                return new XMLHttpRequest();
            }else{
                try{
                    return new ActiveXObject("Msxml2.XMLHTTP");
                }catch(e){
                    return new ActiveXObject("Microsoft.XMLHTTP");
                }
            }
            return null;
        }
        function callback(req){
            if(req.readyState == 4){
                if(req.status != 200){
                    debug("error! req.status:"+req.status+"");
                    return ;
                }
                debug("status.jsp return value:"+req.responseText);
                var ss = req.responseText.split("||");
                $('progressBarItem').style.width = ''+ss[0]+'%';
                $('statusInfo').innerHTML = 'end of total:'+ss[0] +'%<br/>'+
                'sucess of numbers:'+ss[1]+'<br/>'+
                'length of file:'+ss[2]+'<br/>'+
                'velocity of trans:'+ss[3]+'<br/>'+
                'the time used:'+ss[4]+'<br/>'+
                'total time:'+ss[5]+'<br/>'+
                'other time:'+ss[6]+'<br/>'+
                'which is translating:'+ss[7];
                
                if(ss[1] == ss[2]){
                    finished = true;
                    $('statusInfo').innerHTML += "<br/><br/><br/>have done!";
                    $('btnSubmit').disabled = false;
                
                }
            }
        }
        function debug(obj){
            var div = document.createElement("DIV");
            div.innerHTML = "[debug]:"+obj;
            document.body.appendChild(div);
        }
    </script>
  </body>
</html>

UploadStatus.java

package com.test.temp;

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;
    }
}

UploadListener.java

package com.test.temp;

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);
    }
}

PorgressUploadServlet.java

package com.test.hello;

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.Iterator;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

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

import com.test.temp.UploadListener;
import com.test.temp.UploadStatus;

public class ProgressUploadServlet extends HttpServlet {

    /**
     * Constructor of the object.
     */
    public ProgressUploadServlet() {
        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)
            throws ServletException, IOException {
        response.setHeader("Cache-Control","no-store");
        response.setHeader("Pragrma","no-cache");
        response.setDateHeader("Expires",0);
        
        UploadStatus status = (UploadStatus) request.getSession(true).getAttribute("uploadStatus");
        
        if(status == null){
            response.getWriter().println("没有上传信息");
            return;
        }
        
        long startTime = status.getStartTime();
        long currentTime = System.currentTimeMillis();
        long time = (currentTime - startTime)/1000 + 1;
        
        double velocity = ((double)status.getBytesRead())/(double)time;
        
        double totalTime = status.getContentLength()/velocity;
        
        double timeLeft = totalTime - time;
        
        int percent = (int)(100*(double)status.getBytesRead()/(double)status.getContentLength());
        
        double length = ((double)status.getBytesRead())/1024/1024;
        
        double totalLength = ((double)status.getContentLength())/1024/1024;
        
        String value = percent +"||" + length + "||" +totalLength+"||"+
                        velocity+"||"+time+"||"+totalTime+"||"+timeLeft+"||"+status.getItems();
        
        response.getWriter().println(value);
    }

    /**
     * The doPost method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to post.
     * 
     * @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 doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        
        UploadStatus status = new UploadStatus();
        UploadListener listener = new UploadListener(status);
        request.getSession(true).setAttribute("uploadStatus",status);
        
        ServletFileUpload upload = new ServletFileUpload(new DiskFileItemFactory());
        
        upload.setProgressListener(listener);
        
        try{
            List itemList = upload.parseRequest(request);
            for(Iterator it = itemList.iterator();it.hasNext();){
                FileItem item = (FileItem)it.next();
                if(item.isFormField()){
                    System.out.println("FormField:"+item.getFieldName()+"="+item.getString());
                }else{
                    System.out.println("File:"+item.getName());
                    String fileName = item.getName().replace("/","\\");
                    fileName = fileName.substring(fileName.lastIndexOf("\\"));
                    
                    File saved = new File("D:\\upload_temp",fileName);
                    
                    saved.getParentFile().mkdirs();
                    
                    InputStream ins = item.getInputStream();
                    OutputStream ous = new FileOutputStream(saved);
                    
                    byte[] tmp = new byte[1024];
                    int len = -1;
                    while((len = ins.read(tmp)) != -1){
                        ous.write(tmp,0,len);
                    }
                    ous.close();
                    ins.close();
                    response.getWriter().println("已保存文件:"+saved);
                }
            }
        }catch(Exception e){
                response.getWriter().println("上传发生错误:"+e.getMessage());
        }
        
        
//        response.setContentType("text/html");
//        PrintWriter out = response.getWriter();
//        out
//                .println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
//        out.println("<HTML>");
//        out.println("  <HEAD><TITLE>A Servlet</TITLE></HEAD>");
//        out.println("  <BODY>");
//        out.print("    This is ");
//        out.print(this.getClass());
//        out.println(", using the POST method");
//        out.println("  </BODY>");
//        out.println("</HTML>");
//        out.flush();
//        out.close();
    }

    /**
     * Initialization of the servlet. <br>
     *
     * @throws ServletException if an error occurs
     */
    public void init() throws ServletException {
        // Put your code here
    }

}

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
    xmlns="http://java.sun.com/xml/ns/javaee" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
    http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
  <servlet>
    <description>This is the description of my J2EE component</description>
    <display-name>This is the display name of my J2EE component</display-name>
    <servlet-name>PostServlet</servlet-name>
    <servlet-class>com.test.hello.PostServlet</servlet-class>
  </servlet>
  <servlet>
    <description>This is the description of my J2EE component</description>
    <display-name>This is the display name of my J2EE component</display-name>
    <servlet-name>test</servlet-name>
    <servlet-class>com.test.hello.test</servlet-class>
  </servlet>
  <servlet>
    <description>This is the description of my J2EE component</description>
    <display-name>This is the display name of my J2EE component</display-name>
    <servlet-name>UploadServlet</servlet-name>
    <servlet-class>com.test.hello.UploadServlet</servlet-class>
  </servlet>
  <servlet>
    <description>This is the description of my J2EE component</description>
    <display-name>This is the display name of my J2EE component</display-name>
    <servlet-name>ProgressUploadServlet</servlet-name>
    <servlet-class>com.test.hello.ProgressUploadServlet</servlet-class>
  </servlet>



  <servlet-mapping>
    <servlet-name>PostServlet</servlet-name>
    <url-pattern>/servlet/PostServlet</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>test</servlet-name>
    <url-pattern>/servlet/test</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>UploadServlet</servlet-name>
    <url-pattern>/servlet/UploadServlet</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>ProgressUploadServlet</servlet-name>
    <url-pattern>/servlet/ProgressUploadServlet</url-pattern>
  </servlet-mapping>
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
</web-app>

运行结果:

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