ftp

1.ftp上传文件

1.1相关依赖

        <dependency>
            <groupId>commons-net</groupId>
            <artifactId>commons-net</artifactId>
            <version>3.6</version>
        </dependency>

1.2工具类

package com.hungraim.ltc.utils;
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import org.apache.commons.net.ftp.FTP;
import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPConnectionClosedException;
import org.apache.commons.net.ftp.FTPReply;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

public class FtpUpload {
    public static void main(String[] args) throws Exception {
        String host = "121.5.28.29";
        Integer port = 22;
        String userName = "user";
        String password = "123456";
        File file = new File("E:\\DevTool\\image\\a.jpg");
        // ftp
        FTPClient ftpClient = new FTPClient();
        // 设置连接使用的字符编码。必须在建立连接之前设置。
        ftpClient.setControlEncoding("UTF-8");
        try {
            // 连接服务端
            ftpClient.connect(host, port);
            System.out.println("连接服务器" + host + ":" + port);

            // ftp操作可能会返回一些响应信息，可以打印出来看看
            // showServerReply(ftpClient);
            // 尝试连接后，检查响应码以确认成功
            int replyCode = ftpClient.getReplyCode();
            if (!FTPReply.isPositiveCompletion(replyCode)) {
                disconnectQuietly(ftpClient);
                System.out.println("服务器拒绝连接");
                return;
            }
        } catch (IOException e) {
            disconnectQuietly(ftpClient);
            System.out.println("连接ftp失败");
            e.printStackTrace();
            return;
        }

        try {
            // 登录ftp
            boolean success = ftpClient.login(userName, password);
            if (!success) {
                ftpClient.logout();
                System.out.println("客户端登录失败");
                return;
            }
            System.out.println("客户端登录成功");
            // 大部分情况，上传文件时，需要设置这两项
            // 设置文件传输类型为二进制文件类型
            ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
            // 设置被动模式
            ftpClient.enterLocalPassiveMode();


            boolean done = false;
            try (final InputStream input = new FileInputStream(file)) {
                // 设置上传到ftp上使用的文件名和路径
                String remote = "testUpload/" + file.getName();
                // 上传文件
                done = ftpClient.storeFile(remote, input);
            }
            if (done) {
                System.out.println("上传文件" + file.getName() + "成功");
                // ftpClient.completePendingCommand();
            } else {
                System.out.println("上传文件" + file.getName() + "失败");
                showServerReply(ftpClient);
            }

            ftpClient.noop(); // check that control connection is working OK
            ftpClient.logout();
        } catch(FTPConnectionClosedException e) {
            System.out.println("服务端关闭连接");
            e.printStackTrace();
        } catch (IOException e) {
            System.out.println("客户端登录或操作失败");
            e.printStackTrace();
        } finally {

            disconnectQuietly(ftpClient);
        }
    }
    
    /**
     * 断开ftp连接
     */
    public static void disconnectQuietly(FTPClient ftpClient) {
        if (ftpClient.isConnected()) {
            try {
                ftpClient.disconnect();
            } catch (IOException ex) {
                // do nothing
            }
        }
    }

    /**
     * 打印服务器返回信息
     */
    public static void showServerReply(FTPClient ftpClient) {
        String[] replies = ftpClient.getReplyStrings();
        if (replies != null && replies.length > 0) {
            for (String aReply : replies) {
                System.out.println("服务端响应信息: " + aReply);
            }
        }
    }
}

ps:如若出现报错，连接ftp失败，在Telnet以及确认无防火墙拦截的情况下，说明服务器不支持ftpClient连接方式。

org.apache.commons.net.MalformedServerReplyException: Could not parse response code.
Server Reply: SSH-2.0-OpenSSH_8.0
	at org.apache.commons.net.ftp.FTP.__getReply(FTP.java:344)
	at org.apache.commons.net.ftp.FTP.__getReply(FTP.java:300)
	at org.apache.commons.net.ftp.FTP._connectAction_(FTP.java:438)
	at org.apache.commons.net.ftp.FTPClient._connectAction_(FTPClient.java:962)
	at org.apache.commons.net.ftp.FTPClient._connectAction_(FTPClient.java:950)
	at org.apache.commons.net.SocketClient._connect(SocketClient.java:244)
	at org.apache.commons.net.SocketClient.connect(SocketClient.java:202)
	at com.hungraim.ltc.utils.FtpUpload.main(FtpUpload.java:32)

可以尝试以下方式。

2.sftp上传文件

2.1相关依赖

 <dependency>
            <groupId>com.jcraft</groupId>
            <artifactId>jsch</artifactId>
            <version>0.1.49</version>
        </dependency>

2.2工具类

package com.hungraim.ltc.utils;

import com.jcraft.jsch.*;

import java.io.*;
import java.util.Properties;

public class SFTPUtil {
    //用户名
    private String username;
    //密码
    private String password;
    //ip
    private String host;
    //端口一般为22
    private int port;
    //私钥
    private String privateKey;

    ChannelSftp sftp = null;
    //通过构造方法传参
    public FileUtil(String username, String password, String host, int port){
        this.username = username;
        this.password = password;
        this.host = host;
        this.port = port;
    }
    public FileUtil(String username, String host, int port, String privateKey){
        this.username = username;
        this.host = host;
        this.port = port;
        this.privateKey = privateKey;
    }
    //登录，检查链接情况
    public void login(){
        try {
            JSch jSch = new JSch();
            if(privateKey != null){
                jSch.addIdentity(privateKey);
            }
            Session session = jSch.getSession(username,host,port);
            if(password != null){
                session.setPassword(password);
            }
            session.setTimeout(100000);

            Properties config = new Properties();
            config.put("StrictHostKeyChecking", "no");
            session.setConfig(config);
            session.connect();

            Channel channel = session.openChannel("sftp");
            channel.connect();
            sftp = (ChannelSftp) channel;
            System.out.println("登录成功");
        } catch (JSchException e) {
            e.printStackTrace();
        }

    }
    //上传文件
    /**
     * @param basePath 目标路径
     * @param direcotry 目标子路径
     * @param sftpFileName 文件名称
     */
    public void  upload(String basePath, String direcotry, String sftpFileName, InputStream inputStream) throws SftpException{
        try {
            //进入到目标目录
            sftp.cd(basePath);
            sftp.cd(direcotry);
        } catch (SftpException e) {
            String[] dirs = direcotry.split("/");
            String temPath = basePath;
            for (String dir: dirs) {
                if( null == dir || "".equals(dir)) continue;
                temPath +="/" + dir;
                try {
                    sftp.cd(temPath);
                } catch (SftpException ex) {
                    sftp.mkdir(temPath);
                    sftp.cd(temPath);
                }
            }
        }
        sftp.put(inputStream,sftpFileName);
        System.out.println("上传成功");
    }
    //下载文件
    /**
     * @param directory 下载的文件路径
     * @param downloadFile 下载的文件名
     * @param saveFileDirectory 保存的文件路径
     */
    public void download(String directory, String downloadFile, String saveFileDirectory) throws SftpException, FileNotFoundException{
        if(directory != null && !"".equals(directory)){
            sftp.cd(directory);
        }
        String saveFile = saveFileDirectory + "//" + downloadFile;
        File file = new File(saveFile);
        sftp.get(downloadFile, new FileOutputStream(file));
        System.out.println("下载成功");
    }
    //登出




    public static void main(String[] args) throws FileNotFoundException,SftpException {
        FileUtil fiel = new FileUtil("username","pwd","ip",port);
        fiel.login();
        //测试上传功能
        File file = new File("E:\\DevTool\\image\\a.jpg");
        InputStream is = new FileInputStream(file);
        fiel.upload("/projects/gxyx/file","/startSrv","a.jpg",is);
    }
}

亲测可行。