Apache FTP 简单的文件下载

来源：互联网发布：信息对抗技术专业知乎编辑：程序博客网时间：2024/06/01 10:08

这里先做个简单的文件下载例子，先入门再说。

package com.vakinge.ftp;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.SocketException;

import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPFile;
import org.apache.commons.net.ftp.FTPReply;

public class ClientFtpApp {

    private String ip = "localhost";
    private int port = 21;
    private String username = "admin";
    private String password = "admin";

    /**
     * @param args
     */
    public static void main(String[] args) {
        ClientFtpApp ftp = new ClientFtpApp();
        ftp.downLoadFile("c:\\w\\", "./good/", "阿发.txt");
    }

    public void downLoadFile(String localPath, String remotePath, String fileName) {
        FTPFile[] files = null;
        FTPClient client = null;
        try {
            int reply;
            if (client == null) {
                try {
                    client = new FTPClient();
                    client.setControlEncoding("utf-8");
                    client.setDefaultPort(port);
                    client.connect(ip, port);
                    client.login(username, password);
                    reply = client.getReplyCode();
                    client.setDataTimeout(120000);
                    System.out.println(ip + " 连接成功");
                    if (!FTPReply.isPositiveCompletion(reply)) {
                        client.disconnect();
                        System.out.println(ip + " connect refused!");
                    }
                } catch (SocketException e) {
                    e.printStackTrace();
                    System.out.println(ip + " 连接超时!");
                } catch (IOException e) {
                    e.printStackTrace();
                    System.out.println(ip + " 服务器无法打开!");
                }
            }

            client.changeWorkingDirectory(remotePath);
            files = client.listFiles();
            for (FTPFile f : files) {
                if (f.getName().equals(fileName)) {
                    File localFile = new File(localPath + File.separator
                            + fileName);
                    FileOutputStream fos = new FileOutputStream(localFile);
                    client.retrieveFile(fileName, fos);
                    fos.close();
                }
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (client != null) {
                try {
                    client.logout();
                    client.disconnect();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

}

前提：阅读上一篇文章配置ftp server。

在浏览器中输入：ftp://127.0.0.1

右键“登录”，输入用户名和密码 admin/admin

新建good/阿发.txt（可直接从window中拖动过来）

运行上面的程序下载good文件夹内容

可在c:/w目录中看到阿发.txt

参考：

http://vakinge.iteye.com/blog/487486

http://hi.baidu.com/victorlin23/blog/item/edc62a35dbae8a1a91ef3947.html