Applet 通过http上传文件到服务器

 package com.cxsoft.applet;
import java.applet.Applet;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
 
 /****************************************
  * 

Title：UploadFile

    *
  * 

Description：上传文件的applet

 *
  * 

@author jerry

     *
  * 

version: 1.0

     *
  ****************************************/
 
 public class UploadFile extends Applet {
 
  private static final long serialVersionUID = 1L;
 
  public UploadFile() throws Exception {
   
   HttpURLConnection con = this.getConnection();
   con.disconnect();
   
   //处理本地需要上传的文件
   String path = "D:\\EdmsScanDemo\\tm.zip";
   File file = new File(path);
   long fileLength = file.length(); // 获取文件字节数
   System.out.println("要上传的文件大小为：" + fileLength);
   
   //上传文件到服务器
   long startPos = this.getServletObject(con); //获取服务器的返回信息
   
   //判断是否需要上传
   if(startPos  < fileLength) {
    System.err.println("文件未传完，现在开始上传剩余部分");
    this.sendServletObject(con, path, startPos);
   } else {
    System.err.println("该文件已存在！");
   }
  }
 
  /****************************************
   * 

功能：上传文件到服务器

    *
   * 

@param con 与服务器的连接

  *
   * 

@param path 需要上传的文件的路径

 *
   * 

@throws IOException 

   *
   ****************************************/
  private void sendServletObject(HttpURLConnection con, String path, long nstartPos)
    throws Exception {
 
   FileInputStream fis = null;
   BufferedInputStream bis = null;
   con = this.getConnection();
   
   long startPos = nstartPos; //开始上传的位置
   BufferedOutputStream bos = null;
   byte[] buf = new byte[4096]; //定义一个4M的缓存区
   int len = 0; 
   //int totalBytes = 0;
 
   try {
    bos = new BufferedOutputStream(con.getOutputStream());
    fis = new FileInputStream(path);
    bis = new BufferedInputStream(fis);
    bis.skip(startPos);
 
    while ((len = bis.read(buf)) != -1) {
     bos.write(buf, 0, len);  //上传文件
     bos.flush(); //缓存刷新
    }
 
   } catch (Exception e) {
    e.printStackTrace();
   } finally {
    if (bis != null) {
     bis.close();
    }
    if (fis != null) {
     fis.close();
    }
    if (bos != null) {
     bos.flush();
     bos.close();
    }
    buf = null;
   }
  }
  
  /********************************
   * 

功能：获取与服务器的连接

 *
   * 

@return 

   *
   * 

@throws Exception 

 *
   ********************************/
  private HttpURLConnection getConnection() throws Exception{
   String url = "http://localhost:8080/UploadTest/temp";
   String data = "test.zip";
   URL server = new URL(url + "?filename=" + data);
//   System.out.println("url= " + url + "?filename=" + data);
 
   HttpURLConnection con = (HttpURLConnection) server.openConnection(); //获取服务器端连接
   con.setDoInput(true);
   con.setDoOutput(true);
   con.setUseCaches(false);
   con.setDefaultUseCaches(false);
   
   return con;
  }
 
  /********************************************
   * 

Title：getServletObject

   *
   * 

Description：获取服务器端的返回信息

 *
   * 

@param con

      *
   * 

@throws IOException

    *
   ********************************************/
  private long getServletObject(HttpURLConnection con) throws Exception {
   
   //向服务器端发送请求
   ObjectOutputStream  os = new ObjectOutputStream(con.getOutputStream());
   os.write(1);
   os.close();
   
   //获取服务器端的返回信息
   ObjectInputStream ins = new ObjectInputStream(con.getInputStream());
   String nStartPos = ins.readUTF();
   System.out.println("已上传的字节数为：" + nStartPos);
   ins.close();
   
   return Long.parseLong(nStartPos);
  }
  
  public static void main(String[] args) {
   try {
    UploadFile up = new UploadFile();
  } catch (Exception e) {
   e.printStackTrace();
  }
   
 }
 }