Java8实现FTP及SFTP文件上传下载

下面是关于“Java8实现FTP及SFTP文件上传下载”的完整攻略。

一、FTP文件上传下载

1.1 准备工作

在开始前，需要引入以下的Maven依赖：

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

1.2 FTP文件上传

下面是FTP文件上传的主要代码：

public static boolean uploadFile(String host, int port, String username, String password, String basePath, String filePath, String filename, InputStream inputStream) {
    boolean result = false;
    FTPClient ftpClient = new FTPClient();
    ftpClient.setControlEncoding("UTF-8");
    try {
        ftpClient.connect(host, port); // 连接FTP服务器
        ftpClient.login(username, password); // 登录FTP服务器
        if (!FTPReply.isPositiveCompletion(ftpClient.getReplyCode())) {
            ftpClient.disconnect();
            return result;
        }
        ftpClient.changeWorkingDirectory(basePath);
        ftpClient.setFileType(FTPClient.BINARY_FILE_TYPE);
        ftpClient.storeFile((filename), inputStream);
        inputStream.close();
        ftpClient.logout();
        result = true;
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        if (ftpClient.isConnected()) {
            try {
                ftpClient.disconnect();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    return result;
}

示例1：上传本地文件到FTP服务器

public static void main(String[] args) throws FileNotFoundException {
    FileInputStream fis = new FileInputStream(new File("D:\\temp\\test.txt"));
    boolean result = uploadFile("10.10.10.100", 21, "username", "password", "/data/files", "test", "test.txt", fis);
    System.out.println(result);
}

1.3 FTP文件下载

下面是FTP文件下载的主要代码：

public static boolean downloadFile(String host, int port, String username, String password, String remotePath, String fileName, String localPath) {
    boolean result = false;
    FTPClient ftpClient = new FTPClient();
    ftpClient.setControlEncoding("UTF-8");
    try {
        ftpClient.connect(host, port); // 连接FTP服务器
        ftpClient.login(username, password); // 登录FTP服务器
        if (!FTPReply.isPositiveCompletion(ftpClient.getReplyCode())) {
            ftpClient.disconnect();
            return result;
        }
        ftpClient.changeWorkingDirectory(remotePath);// 转移到FTP服务器目录
        FTPFile[] fs = ftpClient.listFiles();
        for (FTPFile ff : fs) {
            if (ff.getName().equals(fileName)) {
                File localFile = new File(localPath + "/" + ff.getName());
                OutputStream os = new FileOutputStream(localFile);
                ftpClient.retrieveFile(ff.getName(), os);
                os.close();
            }
        }
        ftpClient.logout();
        result = true;
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        if (ftpClient.isConnected()) {
            try {
                ftpClient.disconnect();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    return result;
}

示例2：从FTP服务器下载文件到本地

public static void main(String[] args) {
    boolean result = downloadFile("10.10.10.100", 21, "username", "password", "/data/files", "test.txt", "D:\\temp\\download");
    System.out.println(result);
}

二、SFTP文件上传下载

2.1 准备工作

在开始前，需要引入以下的Maven依赖：

<dependency>
    <groupId>com.jcraft</groupId>
    <artifactId>jsch</artifactId>
    <version>0.1.54</version>
</dependency>

2.2 SFTP文件上传

下面是SFTP文件上传的主要代码：

public static boolean uploadFile(String host, int port, String username, String password, String basePath, String filePath, String filename, InputStream inputStream) {
    Session session = null;
    Channel channel = null;
    boolean result = false;
    try {
        JSch jsch = new JSch(); // 创建JSch对象
        session = jsch.getSession(username, host, port); // 根据用户名、主机ip和端口号获取session对象
        session.setPassword(password); // 设置密码
        session.setConfig("StrictHostKeyChecking", "no");
        session.connect(); // 通过Session建立连接
        channel = session.openChannel("sftp"); // 打开SFTP通道
        channel.connect();
        ChannelSftp sftp = (ChannelSftp) channel;
        try {
            sftp.cd(basePath);
        } catch (SftpException e) {
            sftp.mkdir(basePath);
            sftp.cd(basePath);
        }
        sftp.put(inputStream, filename); // 上传文件
        inputStream.close();
        result = true;
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if (session != null) {
            session.disconnect();
        }
        if (channel != null) {
            channel.disconnect();
        }
    }
    return result;
}

示例3：上传本地文件到SFTP服务器

public static void main(String[] args) throws FileNotFoundException {
    FileInputStream fis = new FileInputStream(new File("D:\\temp\\test.txt"));
    boolean result = uploadFile("10.10.10.100", 22, "username", "password", "/data/files", "test", "test.txt", fis);
    System.out.println(result);
}

2.3 SFTP文件下载

下面是SFTP文件下载的主要代码：

public static boolean downloadFile(String host, int port, String username, String password, String remotePath, String fileName, String localPath) {
    Session session = null;
    Channel channel = null;
    boolean result = false;
    try {
        JSch jsch = new JSch(); // 创建JSch对象
        session = jsch.getSession(username, host, port); // 根据用户名、主机ip和端口号获取session对象
        session.setPassword(password); // 设置密码
        session.setConfig("StrictHostKeyChecking", "no");
        session.connect(); // 通过Session建立连接
        channel = session.openChannel("sftp"); // 打开SFTP通道
        channel.connect();
        ChannelSftp sftp = (ChannelSftp) channel;
        sftp.cd(remotePath);
        sftp.get(fileName, localPath); // 下载文件
        result = true;
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if (session != null) {
            session.disconnect();
        }
        if (channel != null) {
            channel.disconnect();
        }
    }
    return result;
}

示例4：从SFTP服务器下载文件到本地

public static void main(String[] args) {
    boolean result = downloadFile("10.10.10.100", 22, "username", "password", "/data/files/test", "test.txt", "D:\\temp\\download");
    System.out.println(result);
}

以上就是Java8实现FTP及SFTP文件上传下载的完整攻略。