import ch.ethz.ssh2.Connection;
import ch.ethz.ssh2.Session;
import ch.ethz.ssh2.StreamGobbler;
import lombok.extern.slf4j.Slf4j;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

/**
 * 登录ssh
 * @param ip
 * @param username
 * @param password
 * @return
 */
public static Connection login(String ip, String username, String password) {
    boolean flag = false;
    Connection connection = null;
    try {
        connection = new Connection(ip);
        connection.connect();// 连接
        flag = connection.authenticateWithPassword(username, password);// 认证
        if (flag) {
            System.out.println("================" + ip + " 登录成功==================");
            return connection;
        }
    } catch (Exception e) {
        log.info("=========登录失败=========" + e);
        if (connection != null)
            connection.close();
        connection = null;
    }
    return connection;
}

/**
 * 远程执行shll脚本或者命令
 *
 * @param cmd 即将执行的命令
 * @return 命令执行完后返回的结果值
 */
public static String execmd(Connection connection, String cmd) {
    String result = "";
    try {
        if (connection != null) {
            Session session = connection.openSession();// 打开一个会话
            session.execCommand(cmd);// 执行命令
            result = processStdout(session.getStdout());
            System.out.println(result);
            // 如果为得到标准输出为空，说明脚本执行出错了
          /*  if (!StringUtils.isEmpty(result)) {
                System.out.println("得到标准输出为空,链接conn:" + connection + ",执行的命令：" + cmd);
                result = processStdout(session.getStderr(), DEFAULTCHART);
            } else {
                System.out.println("执行命令成功,链接conn:" + connection + ",执行的命令：" + cmd);
            }*/
            /*connection.close();
            session.close();*/
        }
    } catch (Exception e) {
        log.info("执行命令失败,链接conn:" + connection + ",执行的命令：" + cmd + "  " + e);
        //     e.printStackTrace();
    }
    return result;
}

/**
 * 解析脚本执行返回的结果集
 *
 * @param in 输入流对象
 * @return 以纯文本的格式返回
 */
private static String processStdout(InputStream in) {
    InputStream stdout = new StreamGobbler(in);
    StringBuffer buffer = new StringBuffer();
    try {
        BufferedReader br = new BufferedReader(new InputStreamReader(stdout, StandardCharsets.UTF_8));
        String line = null;
        while ((line = br.readLine()) != null) {
            buffer.append(line).append("\n");
            //   System.out.println(line);
        }
        br.close();
    } catch (IOException e) {
        log.info("解析脚本出错：" + e.getMessage());
        //   e.printStackTrace();
    }
    return buffer.toString();
}