JAVA如何实现文件的上传下载

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楼主【xhf1234】截止到2008-07-20 13:18:24的历史汇总数据(不包括此帖)：
发帖的总数量:16                       发帖的总分数:990                      每贴平均分数:61
回帖的总数量:18                       得分贴总数量:0                        回帖的得分率:0%
结贴的总数量:15                       结贴的总分数:890
无满意结贴数:0                        无满意结贴分:0
未结的帖子数:1                        未结的总分数:100
结贴的百分比:93.75 %               结分的百分比:89.90 %
无满意结贴率:0.00  %               无满意结分率:0.00  %
值得尊敬

1.服务器端
import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.net.ServerSocket;
import java.net.Socket;public class ServerTest {
    int port = 8821;    void start() {
        Socket s = null;
        try {
            ServerSocket ss = new ServerSocket(port);
            while (true) {
                // 选择进行传输的文件
                String filePath = "D:\\lib.rar";
                File fi = new File(filePath);                System.out.println("文件长度:" + (int) fi.length());                // public Socket accept() throws
                // IOException侦听并接受到此套接字的连接。此方法在进行连接之前一直阻塞。                s = ss.accept();
                System.out.println("建立socket链接");
                DataInputStream dis = new DataInputStream(new BufferedInputStream(s.getInputStream()));
                dis.readByte();                DataInputStream fis = new DataInputStream(new BufferedInputStream(new FileInputStream(filePath)));
                DataOutputStream ps = new DataOutputStream(s.getOutputStream());
                //将文件名及长度传给客户端。这里要真正适用所有平台，例如中文名的处理，还需要加工，具体可以参见Think In Java 4th里有现成的代码。
                ps.writeUTF(fi.getName());
                ps.flush();
                ps.writeLong((long) fi.length());
                ps.flush();                int bufferSize = 8192;
                byte[] buf = new byte[bufferSize];                while (true) {
                    int read = 0;
                    if (fis != null) {
                        read = fis.read(buf);
                    }                    if (read == -1) {
                        break;
                    }
                    ps.write(buf, 0, read);
                }
                ps.flush();
                // 注意关闭socket链接哦，不然客户端会等待server的数据过来，
                // 直到socket超时，导致数据不完整。
                fis.close();
                s.close();
                System.out.println("文件传输完成");
            }        } catch (Exception e) {
            e.printStackTrace();
        }
    }    public static void main(String arg[]) {
        new ServerTest().start();
    }
}

2.socket的Util辅助类
import java.net.*;
import java.io.*;public class ClientSocket {
    private String ip;    private int port;    private Socket socket = null;    DataOutputStream out = null;    DataInputStream getMessageStream = null;    public ClientSocket(String ip, int port) {
        this.ip = ip;
        this.port = port;
    }    /** *//**
     * 创建socket连接
     *
     * @throws Exception
     *             exception
     */
    public void CreateConnection() throws Exception {
        try {
            socket = new Socket(ip, port);
        } catch (Exception e) {
            e.printStackTrace();
            if (socket != null)
                socket.close();
            throw e;
        } finally {
        }
    }    public void sendMessage(String sendMessage) throws Exception {
        try {
            out = new DataOutputStream(socket.getOutputStream());
            if (sendMessage.equals("Windows")) {
                out.writeByte(0x1);
                out.flush();
                return;
            }
            if (sendMessage.equals("Unix")) {
                out.writeByte(0x2);
                out.flush();
                return;
            }
            if (sendMessage.equals("Linux")) {
                out.writeByte(0x3);
                out.flush();
            } else {
                out.writeUTF(sendMessage);
                out.flush();
            }
        } catch (Exception e) {
            e.printStackTrace();
            if (out != null)
                out.close();
            throw e;
        } finally {
        }
    }    public DataInputStream getMessageStream() throws Exception {
        try {
            getMessageStream = new DataInputStream(new BufferedInputStream(socket.getInputStream()));
            return getMessageStream;
        } catch (Exception e) {
            e.printStackTrace();
            if (getMessageStream != null)
                getMessageStream.close();
            throw e;
        } finally {
        }
    }    public void shutDownConnection() {
        try {
            if (out != null)
                out.close();
            if (getMessageStream != null)
                getMessageStream.close();
            if (socket != null)
                socket.close();
        } catch (Exception e) {        }
    }
}

3.客户端
import java.io.BufferedOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.FileOutputStream;public class ClientTest {
    private ClientSocket cs = null;    private String ip = "localhost";// 设置成服务器IP    private int port = 8821;    private String sendMessage = "Windwos";    public ClientTest() {
        try {
            if (createConnection()) {
                sendMessage();
                getMessage();
            }        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }    private boolean createConnection() {
        cs = new ClientSocket(ip, port);
        try {
            cs.CreateConnection();
            System.out.print("连接服务器成功!" + "\n");
            return true;
        } catch (Exception e) {
            System.out.print("连接服务器失败!" + "\n");
            return false;
        }    }    private void sendMessage() {
        if (cs == null)
            return;
        try {
            cs.sendMessage(sendMessage);
        } catch (Exception e) {
            System.out.print("发送消息失败!" + "\n");
        }
    }    private void getMessage() {
        if (cs == null)
            return;
        DataInputStream inputStream = null;
        try {
            inputStream = cs.getMessageStream();
        } catch (Exception e) {
            System.out.print("接收消息缓存错误\n");
            return;
        }        try {
            //本地保存路径，文件名会自动从服务器端继承而来。
            String savePath = "E:\\";
            int bufferSize = 8192;
            byte[] buf = new byte[bufferSize];
            int passedlen = 0;
            long len=0;

            savePath += inputStream.readUTF();
            DataOutputStream fileOut = new DataOutputStream(new BufferedOutputStream(new BufferedOutputStream(new FileOutputStream(savePath))));
            len = inputStream.readLong();

            System.out.println("文件的长度为:" + len + "\n");
            System.out.println("开始接收文件!" + "\n");

            while (true) {
                int read = 0;
                if (inputStream != null) {
                    read = inputStream.read(buf);
                }
                passedlen += read;
                if (read == -1) {
                    break;
                }
                //下面进度条本为图形界面的prograssBar做的，这里如果是打文件，可能会重复打印出一些相同的百分比
                System.out.println("文件接收了" +  (passedlen * 100/ len) + "%\n");
                fileOut.write(buf, 0, read);
            }
            System.out.println("接收完成，文件存为" + savePath + "\n");            fileOut.close();
        } catch (Exception e) {
            System.out.println("接收消息错误" + "\n");
            return;
        }
    }    public static void main(String arg[]) {
        new ClientTest();
    }
}

用jspsmartUpload这个组件SmartUpload upload = new SmartUpload();upload.upload()//上传upload.download()//下载

那个组件可以用于不再是JSP中实现上传下载的情况吗？

强人,我一般都用commons-fileupload.jar包实现

建议使用FTP协议进行传输,自己编的程序,一般功能较为单一.
到是可以自己设计一个C/S架构的软件,但是,建议在TCP协议基础上,再封装一层协议用于多功能的实现.

难道SUN没有开发过这种上传下载的jar包吗?

调试易

JAVA如何实现文件的上传下载

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