使用jsch和commons-pool2为sftp创建连接池

1、引入jsch和common-pool2包

以下为gradle的引入方式，使用maven的可切换为maven的xml引入方式。

implementation group: 'com.jcraft', name: 'jsch', version: "0.1.55"
implementation group: 'org.apache.commons', name: 'commons-pool2', version: "2.11.1"

2、创建SFTP操作对象，内部包含了各种操作方法

package cn.ac.iscas.dmo.db.sftp;

import cn.ac.iscas.dmo.db.api.util.StringUtils;
import cn.ac.iscas.dmo.db.filesystem.base.util.FsCommonUtils;
import cn.ac.iscas.dmo.db.sftp.pool.PoolProp;
import com.jcraft.jsch.*;

import java.io.*;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Iterator;
import java.util.Vector;

/**
 * @author zhuquanwen
 * @version 1.0
 * @date 2022/9/8 9:43
 * @since jdk11
 */
public class Sftp {
    private ChannelSftp channelSftp;
    private Session session;
    private String oriPath;

    public Sftp(PoolProp poolProp) {
        try {
            JSch jsch = new JSch();
            session = jsch.getSession(poolProp.getUsername(), poolProp.getHost(), poolProp.getPort());
            session.setPassword(poolProp.getPassword());
            session.setConfig("StrictHostKeyChecking", "no");
            session.connect(poolProp.getSessionConnectTimeout());
            Channel channel = session.openChannel("sftp");
            channel.connect(poolProp.getChannelConnectedTimeout());
            channelSftp = (ChannelSftp) channel;
            oriPath = channelSftp.pwd();
        } catch (Exception e) {
            e.printStackTrace();
            close();
        }
    }

    /**断开连接*/
    public void close() {
        if (channelSftp != null) {
            try {
                channelSftp.disconnect();
            } catch (Exception ignored) {
            }
        }
        if (session != null) {
            try {
                session.disconnect();
            } catch (Exception ignored) {
            }
        }
    }

    /**验证连接*/
    public boolean validate() {
        try {
            return session.isConnected() && channelSftp.isConnected() /*&&
                    !Objects.isNull(oriPath) && oriPath.equals(channelSftp.pwd())*/;
        } catch (Exception e) {
            return false;
        }
    }

    /**
     * 获取当前工作目录
     * */
    public String pwd() throws SftpException {
        return channelSftp.pwd();
    }

    /**获取当前文件的状态*/
    public SftpATTRS stat(String path) throws SftpException {
        return channelSftp.stat(path);
    }

    /**获取当前文件是否是文件夹*/
    public boolean isDir(String path) throws SftpException {
        return channelSftp.stat(path).isDir();
    }

    /**ls*/
    public Vector ls(String path) throws SftpException {
        return channelSftp.ls(path);
    }

    /**mkdir*/
    public void mkdir(String path) throws SftpException {
        channelSftp.mkdir(path);
    }

    /**mkdirs*/
    public void mkdirs(String path) throws SftpException {
        String[] paths = path.split("/");
        for (int i = 0; i < paths.length; i++) {
            StringBuilder pPath = new StringBuilder();
            for (int j = 0; j <= i; j++) {
                pPath.append("/").append(paths[j]);
            }
            String p = pPath.toString();
            p = p.replaceAll("//+", "/");
            if (exist(p)) {
                if (!isDir(p)) {
                    throw new RuntimeException(String.format("路径:[%s]不是路径", p));
                }
            } else {
                if (!"/".equals(p)) {
                    channelSftp.mkdir(p);
                }
            }
        }
    }

    /**touch*/
    public void touch(String path) throws SftpException {
        // todo 未找到类似touch的方式，暂时以上传一个空文件的方式实现
        String parentPath = path.substring(0, path.lastIndexOf("/"));
        if (StringUtils.isEmpty(parentPath)) {
            parentPath = "/";
        }
        String fileName = path.substring(path.lastIndexOf("/") + 1);
        //如果不存在，创建父目录
        mkdirs(parentPath);
        File tmpFile = null;
        try {
            Path tempFile = Files.createTempFile("tmp", "tmp");
            tmpFile = tempFile.toFile();
            try (FileInputStream fis = new FileInputStream(tmpFile)) {
                channelSftp.cd(parentPath);
                channelSftp.put(fis, fileName);
            }
        } catch (SftpException e1) {
            throw e1;
        } catch (Exception e) {
            throw new RuntimeException("创建文件出错", e);
        } finally {
            if (tmpFile != null) {
                tmpFile.delete();
            }
        }
    }

    /**
     * cp
     * 此实现需要该登录用户已被授权ssh功能
     * */
    public void cp(String src, String dest) {
        ChannelExec channelExec = null;
        StringBuilder runLog = new StringBuilder();
        StringBuilder errLog = new StringBuilder();
        try {
            String command = "cp -r " + src + " " + dest;
            Channel channel = session.openChannel("exec");
            channelExec = (ChannelExec) channel;
            channelExec.setCommand(command);
            channelExec.connect();
            // 获取标准输入流
            BufferedReader inputStreamReader = new BufferedReader(new InputStreamReader(channelExec.getInputStream()));
            // 获取标准错误输入流
            BufferedReader errInputStreamReader = new BufferedReader(new InputStreamReader(channelExec.getErrStream()));
            // 记录命令执行 log
            String line;
            while ((line = inputStreamReader.readLine()) != null) {
                runLog.append(line).append("\n");
            }
            //记录命令执行错误 log
            String errLine;
            while ((errLine = errInputStreamReader.readLine()) != null) {
                errLog.append(errLine).append("\n");
            }
            // 输出 shell 命令执行日志
            System.out.println("exitStatus=" + channelExec.getExitStatus() + ", openChannel.isClosed="
                    + channelExec.isClosed());
            System.out.println("命令执行完成，执行日志如下:");
            System.out.println(runLog);
            System.out.println("命令执行完成，执行错误日志如下:");
            System.out.println(errLog);
            if (errLog.length() > 0) {
                throw new RuntimeException(errLog.toString());
            }
        } catch (RuntimeException e) {
           throw e;
        } catch (Exception e) {
            throw new RuntimeException("复制文件出错", e);
        } finally {
            if (channelExec != null) {
                channelExec.disconnect();
            }
        }
    }

    /**
     * mv
     * 此实现需要该登录用户已被授权ssh功能
     * */
    public void mv(String src, String dest) {
        ChannelExec channelExec = null;
        StringBuilder runLog = new StringBuilder();
        StringBuilder errLog = new StringBuilder();
        try {
            String command = "mv " + src + " " + dest;
            Channel channel = session.openChannel("exec");
            channelExec = (ChannelExec) channel;
            channelExec.setCommand(command);
            channelExec.connect();
            // 获取标准输入流
            BufferedReader inputStreamReader = new BufferedReader(new InputStreamReader(channelExec.getInputStream()));
            // 获取标准错误输入流
            BufferedReader errInputStreamReader = new BufferedReader(new InputStreamReader(channelExec.getErrStream()));
            // 记录命令执行 log
            String line;
            while ((line = inputStreamReader.readLine()) != null) {
                runLog.append(line).append("\n");
            }
            //记录命令执行错误 log
            String errLine;
            while ((errLine = errInputStreamReader.readLine()) != null) {
                errLog.append(errLine).append("\n");
            }
            // 输出 shell 命令执行日志
            System.out.println("exitStatus=" + channelExec.getExitStatus() + ", openChannel.isClosed="
                    + channelExec.isClosed());
            System.out.println("命令执行完成，执行日志如下:");
            System.out.println(runLog);
            System.out.println("命令执行完成，执行错误日志如下:");
            System.out.println(errLog);
            if (errLog.length() > 0) {
                throw new RuntimeException(errLog.toString());
            }
        } catch (RuntimeException e) {
            throw e;
        } catch (Exception e) {
            throw new RuntimeException("移动文件出错", e);
        } finally {
            if (channelExec != null) {
                channelExec.disconnect();
            }
        }
    }

    /**
     * 删除文件
     * */
    @SuppressWarnings("unchecked")
    public void rm(String realPath, boolean r) throws SftpException {
        if (isDir(realPath)) {
            // 文件夹，递归
            Vector vector = ls(realPath);
            if (vector.size() <= 0) {
                // 没有子文件或文件夹，直接删除
                channelSftp.rmdir(realPath);
            } else {
                // 如果有子文件或文件夹，通过r参数判定是否能删除
                if (!r) {
                    throw new RuntimeException(String.format("路径:[%s]中存在子文件或文件夹，无法删除", realPath));
                }
                // 递归
                Iterator<ChannelSftp.LsEntry> iterator = vector.iterator();
                while (iterator.hasNext()) {
                    ChannelSftp.LsEntry lsEntry = iterator.next();
                    String filename = lsEntry.getFilename();
                    if (!".".equals(filename) && !"..".equals(filename)) {
                        rm(FsCommonUtils.optimizationPath(realPath + "/" + filename), r);
                    }
                }
                channelSftp.rmdir(realPath);
            }
        } else {
            // 非文件夹直接删除
            channelSftp.rm(realPath);
        }
    }

    /**
     * 查看当前路径或文件否存在
     * */
    public boolean exist(String path) throws SftpException {
        boolean flag = true;
        if ("/".equals(path)) {
            return true;
        }
        try {
            channelSftp.stat(path);
        } catch (SftpException e) {
            if (e.getMessage() != null && e.getMessage().contains("No such file")) {
                flag = false;
            } else {
                throw e;
            }
        }
        return flag;
    }

    /**
     * 上传文件
     * */
    public void uploadFile(String realPath, InputStream is, boolean append) throws SftpException {
        channelSftp.put(is, realPath, append ? ChannelSftp.APPEND : ChannelSftp.OVERWRITE);
    }

    /**
     * 下载文件
     * */
    public void downloadFile(String path, OutputStream os) throws SftpException {
        channelSftp.get(path, os);
    }

    public ChannelSftp getChannelSftp() {
        return channelSftp;
    }

}

3、连接池属性对象

package cn.ac.iscas.dmo.db.sftp.pool;

import lombok.Data;

/**
 * @author zhuquanwen
 * @version 1.0
 * @date 2022/9/8 9:57
 * @since jdk11
 */
@Data
public class PoolProp {
    /**
     * 池中最小的连接数，只有当 timeBetweenEvictionRuns 为正时才有效
     */
    private int minIdle = 0;

    /**
     * 池中最大的空闲连接数，为负值时表示无限
     */
    private int maxIdle = 8;

    /**
     * 池可以产生的最大对象数，为负值时表示无限
     */
    private int maxActive = 16;

    /**
     * 当池耗尽时，阻塞的最长时间，为负值时无限等待
     */
    private long maxWait = -1;

    /**
     * 从池中取出对象是是否检测可用
     */
    private boolean testOnBorrow = true;

    /**
     * 将对象返还给池时检测是否可用
     */
    private boolean testOnReturn = false;

    /**
     * 检查连接池对象是否可用
     */
    private boolean testWhileIdle = true;

    /**
     * 距离上次空闲线程检测完成多久后再次执行
     */
    private long timeBetweenEvictionRuns = 300000L;


    /**
     * 用户名
     */
    private String username;

    /**
     * 主机
     */
    private String host;

    /**
     * 端口
     */
    private int port;

    /**
     * 密码
     */
    private String password;

    /**
     * session连接超时时间
     */
    private int sessionConnectTimeout = 2000;

    /**
     * sftp-channel连接超时时间
     */
    private int channelConnectedTimeout = 2000;

}

4、连接池

package cn.ac.iscas.dmo.db.sftp.pool;

import cn.ac.iscas.dmo.db.sftp.Sftp;
import org.apache.commons.pool2.BasePooledObjectFactory;
import org.apache.commons.pool2.ObjectPool;
import org.apache.commons.pool2.PooledObject;
import org.apache.commons.pool2.impl.DefaultPooledObject;
import org.apache.commons.pool2.impl.GenericObjectPool;
import org.apache.commons.pool2.impl.GenericObjectPoolConfig;

import java.time.Duration;

/**
 * sftp连接池
 *
 * @author zhuquanwen
 * @version 1.0
 * @date 2022/9/8 9:59
 * @since jdk11
 */
public class SftpPool implements ObjectPool<Sftp> {
    private final GenericObjectPool<Sftp> pool;

    public SftpPool(PoolProp poolProp) {
        pool = new GenericObjectPool<>(new SftpFactory(poolProp), getConfig(poolProp));
    }

    @Override
    public void addObject() throws Exception {
        pool.addObject();
    }

    @Override
    public Sftp borrowObject() throws Exception {
        return pool.borrowObject();
    }

    @Override
    public void clear() {
        pool.clear();
    }

    @Override
    public void close() {
        pool.close();
    }

    @Override
    public int getNumActive() {
        return pool.getNumActive();
    }

    @Override
    public int getNumIdle() {
        return pool.getNumIdle();
    }

    @Override
    public void invalidateObject(Sftp obj) throws Exception {
        pool.invalidateObject(obj);
    }

    @Override
    public void returnObject(Sftp obj) {
        pool.returnObject(obj);
    }

    private static class SftpFactory extends BasePooledObjectFactory<Sftp> {

        private final PoolProp poolProp;

        public SftpFactory(PoolProp poolProp) {
            this.poolProp = poolProp;
        }

        @Override
        public Sftp create() {
            return new Sftp(poolProp);
        }

        @Override
        public PooledObject<Sftp> wrap(Sftp sftp) {
            return new DefaultPooledObject<>(sftp);
        }

        @Override
        public boolean validateObject(PooledObject<Sftp> p) {
            return p.getObject().validate();
        }

        @Override
        public void destroyObject(PooledObject<Sftp> p) {
            p.getObject().close();
        }
    }

    private GenericObjectPoolConfig<Sftp> getConfig(PoolProp poolProp) {
        if (poolProp == null) {
            poolProp = new PoolProp();
        }
        GenericObjectPoolConfig<Sftp> config = new GenericObjectPoolConfig<>();
        config.setMinIdle(poolProp.getMinIdle());
        config.setMaxIdle(poolProp.getMaxIdle());
        config.setMaxTotal(poolProp.getMaxActive());
        config.setMaxWait(Duration.ofMillis(poolProp.getMaxWait()));
        config.setTestOnBorrow(poolProp.isTestOnBorrow());
        config.setTestOnReturn(poolProp.isTestOnReturn());
        config.setTestWhileIdle(poolProp.isTestWhileIdle());
        config.setTimeBetweenEvictionRuns(Duration.ofMillis(poolProp.getTimeBetweenEvictionRuns()));
        return config;
    }

}

5、使用连接池

 PoolProp poolProp = new PoolProp();
//todo 连接池信息先用默认的，这里只设置用户名、密码等信息
poolProp.setUsername("root");
poolProp.setHost("125.2.2.2");
poolProp.setPort(22);
poolProp.setPassword("***");
SftpPool sftpPool = new SftpPool(poolProp);
Sftp sftp = null;
try {
	sftp = sftpPool.borrowObject();
	boolean res = sftp.exist("/root");
} finally {
	sftpPool.returnObject(sftp);
}

6、附几个工具类

package cn.ac.iscas.dmo.db.api.util;

import java.util.Objects;

/**
 * @author zhuquanwen
 * @version 1.0
 * @date 2022/3/8 8:52
 * @since jdk11
 */
public class StringUtils {
    private StringUtils() {
    }

    public static boolean isEmpty(Object str) {
        return (str == null || "".equals(str));
    }

    public static boolean isNotEmpty(Object str) {
        return !isEmpty(str);
    }

    public static String substringAfter(final String str, final String separator) {
        if (isEmpty(str)) {
            return str;
        }
        if (separator == null) {
            return "";
        }
        final int pos = str.indexOf(separator);
        if (pos == -1) {
            return "";
        }
        return str.substring(pos + separator.length());
    }

    public static String trySubstringBetween(final String str, final String open, final String close) {
        final int start = str.indexOf(open);
        if (start != -1) {
            final int end = str.indexOf(close, start + open.length());
            if (end != -1) {
                return str.substring(start + open.length(), end);
            }
        }
        return str;
    }

    public static boolean equalsAny(final CharSequence string, final CharSequence... searchStrings) {
        if (!Objects.isNull(searchStrings)) {
            for (final CharSequence next : searchStrings) {
                if (Objects.equals(string, next)) {
                    return true;
                }
            }
        }
        return false;
    }

}

package cn.ac.iscas.dmo.db.filesystem.base.util;

import cn.ac.iscas.dmo.db.api.model.permission.AuthContext;
import cn.ac.iscas.dmo.db.api.model.permission.Datasource;
import cn.ac.iscas.dmo.db.api.model.permission.Permission;
import cn.ac.iscas.dmo.db.api.util.AuthContextHolder;

import java.math.BigDecimal;
import java.math.RoundingMode;
import java.util.*;

/**
 * @author zhuquanwen
 * @version 1.0
 * @date 2022/6/21 10:44
 * @since jdk11
 */
public class FsCommonUtils {
    private FsCommonUtils() {
    }

    /**
     * 一个KB的字节数
     */
    public static final long KB = 1024L;

    /**
     * 一个MB的字节数
     */
    public static final long MB = 1024 * 1024L;

    /**
     * 一个GB的字节数
     */
    public static final long GB = 1024 * 1024 * 1024L;

    /**
     * 一个TB的字节数
     */
    public static final long TB = 1024 * 1024 * 1024 * 1024L;

    /**
     * 用户目录
     */
    public static final String USER_SPACE_FORMATTER = "/dmo/users/namespace/%s";

    /**
     * URL匹配器
     */
    public static final UrlMatcher URL_MATCHER = new UrlMatcher();

    /**
     * 获取有权限的文件路径
     *
     * @param datasourceName 数据源名称
     * @return java.util.List<java.lang.String>
     * @date 2022/6/21
     * @since jdk11
     */
    public static List<String> getPathPermission(String datasourceName) {
        return Optional.ofNullable(AuthContextHolder.getContext())
                .map(AuthContext::getPermission)
                .map(Permission::getDatasources).flatMap(ds -> ds.stream().filter(d -> d.getName().equalsIgnoreCase(datasourceName)).findFirst())
                .map(Datasource::getFilePaths)
                .orElse(Collections.emptyList());
    }

    /**
     * 修改路径，将// 替换为/, \替换为/, \\替换为/，使得不同操作系统下的文件分割符统一成 / ,防止拼接时\ / 混用
     *
     * @param path 路径
     * @return java.lang.String 替换后的路径
     * @date 2022/6/21
     * @since jdk11
     */
    public static String optimizationPath(String path) {
        path = path.replaceAll("//+", "/")
                .replace("\\", "/")
                .replace("\\\\", "/");
        if (path.endsWith("/")) {
            path = path.substring(0, path.length() - 1);
        }
        return path;
    }

    /**
     * 格式化文件大小
     *
     * @param len 长度
     * @return java.lang.String
     * @date 2022/6/21
     * @since jdk11
     */
    public static String formatSize(long len) {
        if (len < KB) {
            return len + " B";
        } else if (len < MB) {
            return scale(len * 1.0 / KB, 2) + " KB";
        } else if (len < GB) {
            return scale(len * 1.0 / MB, 2) + " MB";
        } else if (len < TB) {
            return scale(len * 1.0 / GB, 2) + " GB";
        } else {
            return scale(len * 1.0 / TB, 2) + " TB";
        }
    }

    /**
     * 对效数取有效数字
     *
     * @param data  数据
     * @param scale 有效位数
     * @return double
     * @date 2022/6/21
     * @since jdk11
     */
    @SuppressWarnings("SameParameterValue")
    public static double scale(double data, int scale) {
        BigDecimal bg = new BigDecimal(data);
        return bg.setScale(scale, RoundingMode.HALF_UP).doubleValue();
    }

    /**
     * 格式化时间
     *
     * @param timeMillis 毫秒数
     * @return java.lang.String
     * @date 2022/6/21
     * @since jdk11
     */
    public static String formatTime(long timeMillis) {
        return DateSafeUtils.format(new Date(timeMillis), DateSafeUtils.PATTERN);
    }

    /**
     * 获取文件深度
     *
     * @param parentPath 路径
     * @return int
     * @date 2022/6/21
     * @since jdk11
     */
    public static int getLevel(String parentPath) {
        if (parentPath.endsWith("/")) {
            parentPath = parentPath.substring(0, parentPath.lastIndexOf("/"));
        }
        parentPath = optimizationPath(parentPath);
        if (Objects.equals("/", parentPath)) {
            return 1;
        }
        return parentPath.split("/").length;
    }

}

转自：
https://blog.csdn.net/u011943534/article/details/126846496