通过Java实现bash命令过程解析

import ch.ethz.ssh2.Connection;
import ch.ethz.ssh2.Session;
import ch.ethz.ssh2.StreamGobbler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;


public class BashUtil {

  private Logger logger = LoggerFactory.getLogger(BashUtil.class);

  private String hostname;

  private String username;

  private String password;

  private int port;

  private Connection conn;

  private BashUtil() {
  }

  public BashUtil(String hostname, String username, String password) {
    this(hostname, username, password, 22);
  }

  public BashUtil(String hostname, String username, String password, Integer port) {
    this.hostname = hostname;
    this.username = username;
    this.password = password;
    if (port == null) {
      port = 22;
    } else {
      this.port = port;
    }
  }

  /**
   * 创建连接并认证
   * @return
   */
  public Boolean connection() {
    try {
      conn = new Connection(hostname, port);
      conn.connect();
      boolean isAuthenticated = conn.authenticateWithPassword(username, password);
      return isAuthenticated;
    } catch (Exception e) {
      e.printStackTrace();
      return false;
    }
  }

  /**
   * 关闭连接
   */
  public void close() {
    try {
      conn.close();
      conn = null;
    } catch (Exception e) {
      e.printStackTrace();
    }
  }

  /**
   * 执行shell命令
   * @param command
   * @return
   */
  public List<String> command(String command) {
    if (conn == null && !connection()) {
      logger.error("Authentication failed.");
      return null;
    }
    List<String> result = new ArrayList<String>();
    try {
      Session sess = conn.openSession();
      sess.execCommand(command);
      InputStream stdout = new StreamGobbler(sess.getStdout());
      InputStream stderr = new StreamGobbler(sess.getStderr());
      BufferedReader br_out = new BufferedReader(new InputStreamReader(stdout, "utf-8"));
      BufferedReader br_err = new BufferedReader(new InputStreamReader(stderr, "utf-8"));
      StringBuffer sb_err = new StringBuffer();
      String line = null;
      while ((line = br_out.readLine()) != null) {
        result.add(line.trim());
      }
      while ((line = br_err.readLine()) != null) {
        sb_err.append(line + "\n");
      }
      if (isNotEmpty(sb_err.toString())) {
        logger.error(sb_err.toString());
        return null;
      }
      return result;
    } catch (Exception e) {
      e.printStackTrace();
    }
    return null;
  }


  private static boolean isEmpty(String content) {
    if (content == null) {
      return true;
    } else {
      return "".equals(content.trim()) || "null".equalsIgnoreCase(content.trim());
    }
  }

  private static boolean isNotEmpty(String content) {
    return !isEmpty(content);
  }

  public static void main(String[] args){
    String hostname = "192.168.123.234";  // 此处根据实际情况，换成自己需要访问的主机IP
    String userName = "root";
    String password = "password";
    Integer port = 22;
    String command = "cd /home/miracle&&pwd&&ls&&cat luna.txt";

    BashUtil bashUtil = new BashUtil(hostname, userName, password, port);
    List<String> resultList = bashUtil.command(command);
    StringBuffer result = new StringBuffer("");
    resultList.forEach(str -> result.append(str + "\n"));

    System.out.println("执行的结果如下: \n" + result.toString());
  }
}

执行的结果如下: 
/home/miracle
luna.txt
Hello, I'm SshUtil.
Nice to meet you.^_^

<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-api -->
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-api</artifactId>
      <version>1.7.21</version>
    </dependency>


    <!-- ssh -->
    <dependency>
      <groupId>ch.ethz.ganymed</groupId>
      <artifactId>ganymed-ssh2</artifactId>
      <version>262</version>
    </dependency>