SftpUtil：FTP操作工具类（上传、下载）

SftpUtil 主要用于FTP的上传下载操作，支持ftp、sftp两种

依赖的jar包：com.jcraft:jsch:0.1.54 org.apache.commons:commons-lang3:3.4 commons-net:commons-net:3.3

public class SftpUtil {

    private SftpUtil(){}

    public static void uploadSftpFile(String ftpHost, int ftpPort, String ftpUserName, String remoteFilepath, String localFilePath, String privateKey) throws JSchException, SftpException  {
        Session session = getSftpSession(ftpHost, ftpPort, ftpUserName, null, privateKey);
        uploadSftpFile(remoteFilepath, localFilePath, session);
    }

    public static void uploadSftpFile(int ftpPort, String ftpHost, String ftpUserName, String remoteFilepath, String localFilePath, String password) throws JSchException, SftpException {
        Session session = getSftpSession(ftpHost, ftpPort, ftpUserName, password, null);
        uploadSftpFile(remoteFilepath, localFilePath, session);
    }

    private static void uploadSftpFile(String remoteFilepath, String localFilePath, Session session) throws JSchException, SftpException {
        Channel channel = session.openChannel("sftp");
        channel.connect();
        ChannelSftp chSftp = (ChannelSftp) channel;

        try {
            chSftp.put(localFilePath, remoteFilepath);
        } finally {
            chSftp.quit();
            channel.disconnect();
            session.disconnect();
        }
    }

    public static void uploadFtpFile(int ftpPort, String ftpHost, String ftpUserName, String remoteFilepath, String localFilePath, String password) throws JSchException, SftpException, IOException {
        FTPClient ftpClient = null;
        InputStream in = null;
        try {
            ftpClient = getFtpClient(ftpHost, ftpPort, ftpUserName, password);
            ftpClient.setControlEncoding("UTF-8"); // 中文支持  
            ftpClient.setFileType(FTPClient.BINARY_FILE_TYPE);  
            ftpClient.enterLocalPassiveMode();
            in = new FileInputStream(localFilePath);
            boolean storeFile = ftpClient.storeFile(remoteFilepath, in);
            if(!storeFile) {
                in.close();
                ftpClient.disconnect();
                throw new PosloanException("-999", "upload failed!");
            }
        } finally {
            if(in != null) in.close();
            if(ftpClient != null)
                ftpClient.disconnect();
        }

    }

    /**
     * 通过sftp下载文件数据
     * @param ftpHost
     * @param ftpUserName
     * @param ftpPort
     * @param remoteFile
     * @param localFilePath
     * @throws JSchException
     * @throws SftpException
     */
    public static void downloadSftpFile(String ftpHost, int ftpPort, String ftpUserName, String remoteFilepath, String localFilePath, String privateKey) throws JSchException, SftpException {
        Session session = getSftpSession(ftpHost, ftpPort, ftpUserName, null, privateKey);
        downloadSftpFile(remoteFilepath, localFilePath, session);
    }

    public static void downloadSftpFile(int ftpPort, String ftpHost, String ftpUserName, String remoteFilepath, String localFilePath, String password) throws JSchException, SftpException {
        Session session = getSftpSession(ftpHost, ftpPort, ftpUserName, password, null);
        downloadSftpFile(remoteFilepath, localFilePath, session);
    }
    /**
     * 通过ftp下载文件数据
     * @param ftpPort
     * @param ftpHost
     * @param ftpUserName
     * @param remoteFilepath
     * @param localFilePath
     * @param password
     * @throws JSchException
     * @throws SftpException
     * @throws IOException
     */
    public static void downloadFtpFile(int ftpPort, String ftpHost, String ftpUserName, String remoteFilepath, String localFilePath, String password) throws JSchException, SftpException, IOException, PosloanException {
        FTPClient ftpClient = null;
        OutputStream out = null;
        try {
            ftpClient = getFtpClient(ftpHost, ftpPort, ftpUserName, password);
            FTPFile[] listFiles = ftpClient.listFiles(remoteFilepath);
            if(listFiles.length == 0) {
                throw new PosloanException("", String.format("下载文件不存在，文件路径：%s", remoteFilepath));
            }
            out =new FileOutputStream(localFilePath);
            ftpClient.setFileType(FTP.BINARY_FILE_TYPE);

            ftpClient.retrieveFile(remoteFilepath, out);
        } finally {
            if(out != null) out.close();
            if(ftpClient != null) ftpClient.disconnect();
        }
    }
    /**
     * 下载文件
     * */
    private static void downloadSftpFile(String remoteFilepath, String localFilePath, Session session) throws JSchException, SftpException {
        Channel channel = session.openChannel("sftp");
        channel.connect();
        ChannelSftp chSftp = (ChannelSftp) channel;

        try {
            if (remoteFilepath.startsWith("/")) {
                chSftp.cd("/");
            }
            chSftp.get(remoteFilepath, localFilePath);
        } finally {
            chSftp.quit();
            channel.disconnect();
            session.disconnect();
        }
    }
    /**
     * 获取sftp连接session
     * */
    private static Session getSftpSession(String ftpHost, int ftpPort, String ftpUserName, String password, String privateKey) throws JSchException {
        JSch jsch = new JSch();
        if(StringUtils.isNotBlank(privateKey)) {
            jsch.addIdentity(privateKey);
        }
        Session session = jsch.getSession(ftpUserName, ftpHost, ftpPort);
        session.setTimeout(100000);
        if(StringUtils.isNotBlank(password)) {
            session.setPassword(password);
        }

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

        return session;
    }

    /**
     * 获取ftp客服端
     */
    private static FTPClient getFtpClient(String ftpHost, int ftpPort, String ftpUserName, String password) throws IOException {
        FTPClient ftpClient = new FTPClient();
        ftpClient.connect(ftpHost,ftpPort);
        ftpClient.login(ftpUserName, password);
        int reply = ftpClient.getReplyCode();
        ftpClient.setDataTimeout(60000);
        if (!FTPReply.isPositiveCompletion(reply)) {
            ftpClient.disconnect();
            throw new PosloanException("-999", "FTP server refuse connect！");
        }
        return ftpClient;
    }    
}