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;

/****************************************

* <p>Title：UploadFile </p> *

* <p>Description：上传文件的applet </p> *

* <p>@author jerry </p> *

* <p>version: 1.0 </p> *

****************************************/

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！");

}

}

/****************************************

* <p>功能：上传文件到服务器 </p> *

* <p>@param con 与服务器的连接 </p> *

* <p>@param path 需要上传的文件的路径 </p> *

* <p>@throws IOException </p> *

****************************************/

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;

}

}

/********************************

* <p>功能：获取与服务器的连接 </p> *

* <p>@return </p> *

* <p>@throws Exception </p> *

********************************/

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;

}

/********************************************

* <p>Title：getServletObject </p> *

* <p>Description：获取服务器端的返回信息 </p> *

* <p>@param con </p> *

* <p>@throws IOException </p> *

********************************************/

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();

}

}

}