jjava Apache ssh断线重连

你可以使用 Apache Commons Net 库来实现 SSH 断线重连。具体步骤如下：

1. 在 Maven 项目中添加 Apache Commons Net 依赖：

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

2. 创建 SSH 连接：

import org.apache.commons.net.util.TrustManagerUtils;
import org.apache.commons.net.util.SubnetUtils;
import org.apache.commons.net.util.SubnetUtils.SubnetInfo;
import org.apache.commons.net.util.SSLContextUtils;

import java.io.IOException;
import java.net.SocketException;
import java.util.Arrays;

import org.apache.commons.net.SocketClient;
import org.apache.commons.net.ftp.FTP;
import org.apache.commons.net.ftp.FTPReply;
import org.apache.commons.net.ftp.FTPSClient;
import org.apache.commons.net.imap.IMAPClient;
import org.apache.commons.net.imap.IMAPSClient;
import org.apache.commons.net.nntp.NNTPClient;
import org.apache.commons.net.nntp.NNTPSClient;
import org.apache.commons.net.smtp.SMTPClient;
import org.apache.commons.net.smtp.SMTPSClient;
import org.apache.commons.net.telnet.TelnetClient;
import org.apache.commons.net.telnet.TelnetOption;
import org.apache.commons.net.tftp.TFTP;
import org.apache.commons.net.tftp.TFTPClient;
import org.apache.commons.net.util.KeyManagerUtils;

public class SSHConnection {

    private static final int SSH_PORT = 22;

    private final String host;
    private final int port;
    private final String username;
    private final String password;

    private SSHConnection(String host, int port, String username, String password) {
        this.host = host;
        this.port = port;
        this.username = username;
        this.password = password;
    }

    public static SSHConnection create(String host, int port, String username, String password) {
        return new SSHConnection(host, port, username, password);
    }

    public boolean connect() {
        try {
            SSHClient sshClient = new SSHClient();
            sshClient.addHostKeyVerifier(new PromiscuousVerifier());
            sshClient.connect(host, port);
            sshClient.authPassword(username, password);
            sshClient.startSession();
            return true;
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
    }

    // 断线重连方法
    public boolean reconnect() {
        try {
            SSHClient sshClient = new SSHClient();
            sshClient.addHostKeyVerifier(new PromiscuousVerifier());
            sshClient.connect(host, port);
            sshClient.authPassword(username, password);
            sshClient.startSession();
            return true;
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
    }

    public void disconnect() {
        sshClient.disconnect();
    }

}

3. 创建一个自定义的 HostKeyVerifier 类，用于验证 SSH 服务器的密钥：

import net.schmizz.sshj.transport.verification.HostKeyVerifier;

public class PromiscuousVerifier implements HostKeyVerifier {

    @Override
    public boolean verify(String arg0, int arg1, PublicKey arg2) {
        return true;
    }

    @Override
    public boolean verify(String arg0, int arg1, PublicKey arg2, boolean arg3) {
        return true;
    }

}

4. 在需要使用 SSH 连接的地方，调用 `connect()` 方法连接服务器，如果连接失败，则调用 `reconnect()` 方法进行重连。

public static void main(String[] args) {
    SSHConnection sshConnection = SSHConnection.create("192.168.0.1", SSH_PORT, "username", "password");
    if (!sshConnection.connect()) {
        System.out.println("连接失败，尝试重连...");
        if (!sshConnection.reconnect()) {
            System.out.println("重连失败！");
        }
    } else {
        System.out.println("连接成功！");
        sshConnection.disconnect();
    }
}

此外，还可以使用线程来实现 SSH 断线重连，如下：

public static void main(String[] args) {
    SSHConnection sshConnection = SSHConnection.create("192.168.0.1", SSH_PORT, "username", "password");
    Thread thread = new Thread(() -> {
        while (true) {
            if (!sshConnection.connect()) {
                System.out.println("连接失败，尝试重连...");
                if (!sshConnection.reconnect()) {
                    System.out.println("重连失败！");
                    break;
                }
            } else {
                System.out.println("连接成功！");
                sshConnection.disconnect();
                break;
            }
        }
    });
    thread.start();
}