linux 安装sftp及使用sftp工具类上传和下载

一、centos7 安装sftp

1.安装 OpenSSH 服务：

sudo yum install openssh-server

2.启动 SSH 服务，并设置为开机启动：

sudo systemctl start sshd
sudo systemctl enable sshd

3.创建一个新用户，用于SFTP连接（替换your_username为你想要的用户名）,设置密码（替换sftpadmin为你想要的密码）：

sudo adduser your_username

sudo passwd sftpadmin

注意：如果输入密码提示未知的用户，则把sftpadmin换成指定的用户，然后再设置新密码
在这里插入图片描述

4.创建一个目录，用于SFTP的根目录（替换/path/to/sftp_root为你想要的目录路径）：

sudo mkdir -p /path/to/sftp_root
sudo chown root:root /path/to/sftp_root
sudo chmod 755 /path/to/sftp_root

5.创建用户的SFTP目录：

sudo mkdir -p /path/to/sftp_root/your_username
sudo chown your_username:your_username /path/to/sftp_root/your_username
sudo chmod 755 /path/to/sftp_root/your_username

6.重启 SSH 服务以应用更改：

sudo systemctl restart sshd

现在，用户 your_username 可以通过 SFTP 连接到服务器，只需要使用他们的常规用户名和密码。确保为用户设置了合适的权限和所需的目录结构。

二、java sftp工具类

1.工具类

（1）引入manven

<dependency>
    <groupId>com.github.mwiede</groupId>
    <artifactId>jsch</artifactId>
    <version>0.2.18</version>
</dependency>

（2）sftp工具类

package com.dcqq.common.utils;

import cn.hutool.core.codec.Base64;
import com.google.common.base.Joiner;
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.RandomUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.time.DateFormatUtils;

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

/**
 * SFTP工具类
 */
@Slf4j
public class SftpUtils {
    private static Session sshSession = null;
    private static String sftpRootDir = "/home/sftp/upload/";//根目录
    private final static String host = "10.122.156.10";//ip
    private final static Integer port = 22;//端口
    private final static String username = "sftp_user";//用户名
    private final static String password = "sftp1122";//密码
    private final static int MAX_TIMES = 3;//重试次数

    public static ChannelSftp connect() {
        // 重试次数
        int count = 0;
        ChannelSftp sftp = SftpUtils.connect(host, port, username, password);
        while (sftp == null && count < MAX_TIMES) {
            count++;
            log.error("第[" + count + "]次重试连接FTP服务器：" + host);
            SftpUtils.sleep(RandomUtils.nextInt(3, 600));
            sftp = SftpUtils.connect(host, port, username, password);
        }
        if (sftp == null) {
            log.error("获取FTP连接失败：" + host);
        }
        return sftp;
    }

    /**
     * 获取ChannelSftp
     */
    public static ChannelSftp connect(String host, Integer port, String username, String password) {
        ChannelSftp sftp = null;
        try {
            JSch jsch = new JSch();
            jsch.getSession(username, host, port);
            sshSession = jsch.getSession(username, host, port);
            sshSession.setPassword(password);
            Properties sshConfig = new Properties();
            sshConfig.put("StrictHostKeyChecking", "no");
            sshSession.setConfig(sshConfig);
            sshSession.connect();
            Channel channel = sshSession.openChannel("sftp");
            channel.connect();
            sftp = (ChannelSftp) channel;
            SftpUtils.mkdirs(sftpRootDir, sftp);
            SftpUtils.cd(sftpRootDir, sftp);
//            System.out.println("连接成功");
            return sftp;
        } catch (Exception e) {
//            e.printStackTrace();
            log.error("连接FTP失败：" + host + "，异常信息：" + e);

        }
        return null;
    }

    public static boolean upload(File file, String directory, String fileName) {
        InputStream inputStream = null;
        try {
            inputStream = new FileInputStream(file);
            return upload(inputStream, directory, fileName);
        } catch (Exception e) {
            e.printStackTrace();
            log.error("FTP文件上传失败：" + directory + "/" + fileName + ",异常标题：" + e.getMessage());
        } finally {
            CloseUtils.closeQuietly(inputStream);
        }
        return false;
    }

    public static boolean upload(byte[] data, String directory, String fileName) {
        ByteArrayInputStream inputStream = null;
        try {
            inputStream = new ByteArrayInputStream(data);
            return upload(inputStream, directory, fileName);
        } finally {
            CloseUtils.closeQuietly(inputStream);
        }
    }

    public static boolean upload(InputStream inputStream, String directory, String fileName) {
        try {
            // 重试次数
            int count = 0;
            boolean success = doUpload(inputStream, directory, fileName);
            while (!success && count < MAX_TIMES) {
                count++;
                log.info("第[{}/{}]次重新上传文件:{}", count, MAX_TIMES, fileName);
                SftpUtils.sleep(RandomUtils.nextInt(1, 300));
                success = doUpload(inputStream, directory, fileName);
            }
            return success;
        } finally {
            CloseUtils.closeQuietly(inputStream);
        }
    }

    private static boolean doUpload(InputStream inputStream, String directory, String fileName) {
        ChannelSftp sftp = SftpUtils.connect();
        if (sftp == null) {
            return false;
        }
        try {
            SftpUtils.mkdirs(directory, sftp);
            sftp.put(inputStream, fileName, ChannelSftp.OVERWRITE);
            return true;
        } catch (Exception e) {
//            throw new RuntimeException(e);
            log.error("FTP文件上传失败：" + directory + "/" + fileName + ",异常标题：" + e.getMessage());
        } finally {
            SftpUtils.disconnect(sshSession);
            SftpUtils.disconnect(sftp);
        }
        return false;
    }

    public static String downloadAsBase64(String fileName) {
        ByteArrayOutputStream outputStream = download(fileName);
        try {
            if (outputStream == null || outputStream.toByteArray().length == 0) {
                return "";
            }
            return Base64.encode(outputStream.toByteArray());
        } finally {
            CloseUtils.closeQuietly(outputStream);
        }
    }

    public static ByteArrayOutputStream download(String fileName) {
        if (StringUtils.isEmpty(fileName)) {
            return null;
        }
        // 重试次数，最多6次
        int count = 0;
        ByteArrayOutputStream outputStream = doDownload(fileName);
        while (outputStream == null && count < MAX_TIMES) {
            count++;
            log.info("第[{}/2]次重新下载文件:{}", count, fileName);
            SftpUtils.sleep(RandomUtils.nextInt(1, 30));
            outputStream = doDownload(fileName);
        }
        return outputStream;
    }

    public static ByteArrayOutputStream doDownload(String fileName) {
        if (StringUtils.isEmpty(fileName)) {
            return null;
        }
        ChannelSftp sftp = SftpUtils.connect();
        try {
            ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
            sftp.get(fileName, outputStream);
            return outputStream;
        } catch (Exception e) {
//            throw new RuntimeException(e);
            log.error("FTP文件下载失败：" + fileName + ",异常标题：" + e.getMessage());
            if ("No such file.".equals(e.getMessage())) {
                return new ByteArrayOutputStream();
            }
        } finally {
            SftpUtils.disconnect(sshSession);
            SftpUtils.disconnect(sftp);
        }
        return null;
    }

    public static ChannelSftp cd(String directory, ChannelSftp sftp) {
        try {
            sftp.cd(directory);
        } catch (Exception e) {
        }
        return sftp;
    }

    public static ChannelSftp mkdir(String directory, ChannelSftp sftp) {
        try {
            sftp.mkdir(directory);
        } catch (Exception e) {
        }
        return sftp;
    }

    public static void disconnect(Session sshSession) {
        if (sshSession != null) {
            try {
                sshSession.disconnect();
            } catch (Exception e) {
            }
        }
    }

    public static void disconnect(ChannelSftp sftp) {
        if (sftp != null) {
            try {
                sftp.disconnect();
            } catch (Exception e) {
            }
        }
    }


    public static void mkdirs(String directory, ChannelSftp sftp) {

        String[] dirs = directory.split("/");
        for (int i = 0; i < dirs.length; i++) {
            String d = dirs[i];
            if (d.length() > 0) {

                SftpUtils.mkdir(d, sftp);
                SftpUtils.cd(d, sftp);
            }
        }
    }

    public static String datePath(String moduleName, Date dateTime) {
        return Joiner.on("/").join(moduleName, DateFormatUtils.format(dateTime, "yyyy/MM/dd"));
    }

    public static String datePath(String moduleName) {
        return Joiner.on("/").join(moduleName, DateFormatUtils.format(System.currentTimeMillis(), "yyyy/MM/dd"));
    }

    public static String fileFullPath(String filePath, String fileName) {
        return Joiner.on("/").join(filePath, fileName);
    }

    /**
     * 删除文件
     *
     * @param directory  要删除文件所在目录
     * @param deleteFile 要删除的文件
     * @throws Exception
     */
    public void delete(String directory, String deleteFile) throws Exception {
        ChannelSftp sftp = SftpUtils.connect();
        if (sftp != null) {
            sftp.cd(directory);
            sftp.rm(deleteFile);
        }
    }

    /**
     * 列出目录下的文件
     *
     * @param directory 要列出的目录
     * @return list 文件名列表
     * @throws Exception
     */
    @SuppressWarnings("unchecked")
    public static List<String> listFiles(String directory) throws Exception {
        ChannelSftp sftp = SftpUtils.connect();
        Vector fileList;
        List<String> fileNameList = new ArrayList<String>();
        fileList = sftp.ls(directory);
        Iterator it = fileList.iterator();
        while (it.hasNext()) {
            String fileName = ((ChannelSftp.LsEntry) it.next()).getFilename();
            if (".".equals(fileName) || "..".equals(fileName)) {
                continue;
            }
            fileNameList.add(fileName);
        }
        return fileNameList;
    }

    /**
     * @param millis *         the length of time to sleep in milliseconds
     */
    public static void sleep(long millis) {
        try {
            Thread.sleep(millis);
        } catch (Exception e) {
        }
    }

    public static void main(String[] args) throws Exception {
        //this.delete("/userReport/1/2022/ //删除
        //显示目录
        /*List<String> list = listFiles(sftpRootDir);
        for (String s : list) {
            System.out.println(s);
        }*/

        //上传文件
        File reportFile = new File("C:\\图片\\1.png");
        upload(reportFile, "upload", "1.png");

    }
}

（3）相关代码

CloseUtils

package com.dcqq.common.utils;

import java.io.Closeable;
import java.util.zip.ZipInputStream;

/**
 * 关闭文件流
 *
 */
public class CloseUtils {

    /**
     * 关闭文件流
     *
     * @param closeables
     */
    public static void closeQuietly(Closeable... closeables) {
        if (closeables != null && closeables.length > 0) {

            for (Closeable closeable : closeables) {

                if (closeable != null) {
                    try {
                        closeable.close();
                    } catch (Exception e) {}
                }
            }
        }
    }

    public static void closeEntryQuietly(ZipInputStream... closeables) {
        if (closeables != null && closeables.length > 0) {
            for (ZipInputStream closeable : closeables) {
                if (closeable != null) {
                    try {
                        closeable.closeEntry();
                    } catch (Exception e) { }
                }
            }
        }
    }
}

2.使用

（1）controller层，CommFileManagerController 公共文件管理层

package com.dcqq.common;

import com.dcqq.system.service.IFileService;
import com.dcqq.web.controller.common.CommonController;
import io.swagger.annotations.Api;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 文件下载
 */
@RestController
@Api(tags = "文件下载")
@RequestMapping("/fileManager")
public class CommFileManagerController {
    private static final Logger log = LoggerFactory.getLogger(CommFileManagerController .class);
    
    @Autowired
    private IFileService fileService;
    @Autowired
    private ServerConfig serverConfig;

	/**
     * 文件上传
     */
    @ApiOperation(value = "文件上传", notes = "文件上传")
    @PostMapping("/uploadFile")
    public AjaxResult uploadFile(MultipartFile file) {
        FileForm form = new FileForm();
        form.setUrl(serverConfig.getUrl());
        return fileService.uploadFile(file, form);
    }

    /**
     * 文件读取
     * @param request
     * @param response
     * @throws IOException
     *  访问示例：https://test.tt.com.cn/prod-api/fileManager/upload/2024/06/18/1_20240618103039A005.png
     */
    @GetMapping(value = "/upload/**")
    public void upload(HttpServletRequest request, HttpServletResponse response){
        log.info("============upload");
        fileService.download(request,response);
    }
}

（2）service业务层

IFileService

package com.dcqq.system.service;

import com.dcqq.common.core.domain.AjaxResult;
import com.dcqq.form.FileForm;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 文件
 * 
 * @author dcqq
 * @date 2024-04-03
 */
public interface IFileService {

    /**
     * 文件上传
     * @param file
     * @return
     */
    AjaxResult uploadFile(MultipartFile file, FileForm form);
    
    /**
     * 文件下载
     * @param request
     * @param response
     */
    void download(HttpServletRequest request, HttpServletResponse response);
}

FileServiceImpl

package com.dcqq.common;

import cn.hutool.core.io.file.FileNameUtil;
import cn.hutool.core.net.URLDecoder;
import com.dcqq.common.core.domain.AjaxResult;
import com.dcqq.common.utils.*;
import com.dcqq.common.utils.file.MimeTypeUtils;
import com.dcqq.form.FileForm;
import com.dcqq.system.service.IFileService;
import org.apache.commons.io.FilenameUtils;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.Objects;

/**
 * 文件
 * 
 * @author dcqq
 * @date 2024-04-03
 */
@Service
public class FileServiceImpl implements IFileService {

    public AjaxResult uploadFile(MultipartFile file, FileForm form) {
        try {
            String url = form.getUrl()+"/prod-api"+"/fileManager/upload";
            String dir=DateUtils.datePath();
            
            //获取文件后缀名
			String extension = FilenameUtils.getExtension(file.getOriginalFilename());
	        if (StringUtils.isEmpty(extension)) {
	            extension = MimeTypeUtils.getExtension(Objects.requireNonNull(file.getContentType()));
	        }

			//获取文件名+后缀
			String fileName = file.getOriginalFilename()+"."+extension;
			
            SftpUtils.upload(file.getBytes(), dir, fileName);
            
            AjaxResult ajax = AjaxResult.success();
			
			url=url+dir+fileName;

            ajax.put("url", url);
            ajax.put("newFileName", fileName);
            ajax.put("originalFilename", file.getOriginalFilename());
            return ajax;
        } catch (Exception e) {
            return AjaxResult.error(e.getMessage());
        }
    }

    @Override
    public void download(HttpServletRequest request, HttpServletResponse response) {
        try {
            String requestURI = URLDecoder.decode(request.getRequestURI(), StandardCharsets.UTF_8);
            // ContentType，即告诉客户端所发送的数据属于什么类型
            String ext = FileNameUtil.extName(requestURI);
            MediaTypeEnum mediaType = MediaTypeEnum.byCode(ext);
            response.setContentType(mediaType.getName());
            String ftpPath = StringUtils.substringAfter(requestURI, "/download/");
            ByteArrayOutputStream out = SftpUtils.download(ftpPath);
            response.getOutputStream().write(out.toByteArray());
            response.flushBuffer();
            CloseUtils.closeQuietly(out, response.getOutputStream());
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }
}

（3）相关代码

MediaTypeEnum

package com.dcqq.common.utils;

import lombok.Getter;
import org.springframework.http.MediaType;

import java.util.HashMap;
import java.util.Map;

/**
 * 媒体类型
 */
@Getter
public enum MediaTypeEnum {
    PNG("png", MediaType.IMAGE_PNG_VALUE),
    JPG("jpg", "image/jpg"),
    JPEG("jpeg", MediaType.IMAGE_JPEG_VALUE),
    PDF("pdf", MediaType.APPLICATION_PDF_VALUE),
    ZIP("zip", "application/zip"),
    DOCX("docx", MediaType.APPLICATION_OCTET_STREAM_VALUE),
    STREAM("other", MediaType.APPLICATION_OCTET_STREAM_VALUE),
    XML("xml", MediaType.APPLICATION_XML_VALUE),
    JSON("json", MediaType.APPLICATION_JSON_VALUE)
    ;
    private String code;
    private String name;

    private static Map<String, MediaTypeEnum> cacheEnum = new HashMap<>();

    static {
        for(MediaTypeEnum dictEnum:MediaTypeEnum.values()){
            cacheEnum.put(dictEnum.code, dictEnum);
        }
    }
    public static MediaTypeEnum byCode(String code){
        if(cacheEnum.containsKey(code)){
            return cacheEnum.get(code);
        }
        return STREAM;
    }

    MediaTypeEnum(String code, String name){
        this.code = code;
        this.name = name;
    }
}

ServerConfig

package com.dcqq.framework.config;

import javax.servlet.http.HttpServletRequest;

import org.springframework.stereotype.Component;
import com.dcqq.common.utils.ServletUtils;

/**
 * 服务相关配置
 *
 * @author ruoyi
 */
@Component
public class ServerConfig {
    /**
     * 获取完整的请求路径，包括：域名，端口，上下文访问路径
     *
     * @return 服务地址
     */
    public String getUrl() {
        HttpServletRequest request = ServletUtils.getRequest();
        return getDomain(request);
    }

    public static String getDomain(HttpServletRequest request) {
        StringBuffer url = request.getRequestURL();
        String contextPath = request.getServletContext().getContextPath();
        return url.delete(url.length() - request.getRequestURI().length(), url.length()).append(contextPath).toString();
    }
}

FileForm

package com.dcqq.form;

import io.swagger.annotations.ApiModelProperty;
import lombok.Data;

@Data
public class FileForm {
    @ApiModelProperty("请求路径")
    private String url;
}