ssh2远程连接linux服务器

做东西的时候遇到了需要远程连接我们的服务器，首先想到的当然是ssh2协议，在查资料的时候将常见的几种jar包都试了个遍，首先说知名的ganymed-ssh2.jar 包，接下来我们在述说jsch-0.1.53.jar,最后，在谈一下我们使用的trilead-ssh2-build13.jar.

ganymed-ssh2.jar :

        这个包是纯java代码写得，使用的实例代码如下，

package com.hemin.test;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Scanner;

import ch.ethz.ssh2.Connection;
import ch.ethz.ssh2.Session;
import ch.ethz.ssh2.StreamGobbler;
public class SshTest

{

    public static void main(String[] args)

    {

       String hostname = "you ip adress";

       String username = "root";

       String password = "root";
       
       boolean  flag = true;
       
       Scanner in = new Scanner(System.in);
       
       try{
           Connection conn = new Connection(hostname);
           conn.connect();
           boolean isAuthenticated = conn.authenticateWithPassword(username, password);
           if (isAuthenticated == false)
              throw new IOException("Authentication failed.");
           Session sess = conn.openSession();

    	   for(int i = 0;i<100;i++){
    		   sess.execCommand(in.nextLine());
    		   System.out.println("Result::");
               InputStream stdout = new StreamGobbler(sess.getStdout());
               BufferedReader br = new BufferedReader(new InputStreamReader(stdout));
               while (true)
               {
                  String line = br.readLine();
                  if (line == null)
                      break;
                  System.out.println(line);
                  sess.close();
                  conn.close();
               }
    	   } 

          
           
           //System.out.println("ExitCode: " + sess.getExitStatus());
          

       }
       catch (IOException e)
       {
           e.printStackTrace(System.err);
           System.exit(2);
       }
    }
}

在使用的过程中，我们需要通过他来提交spark指令，出现的问题就是指令提交上去之后，spark的任务一直运行，停不下来，因此，只能选择放弃。不得不说，这个包确实很好用，可以使用多线程而实现防putty这个知名软件。有兴趣的可以试试这个。

----------------------------------------------------------------------------

jsch-0.1.53.jar

这个包也是纯jiava的ssh2包，示例代码和上述大同小异，直接上程序

package com.hemin.test;

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

import com.jcraft.jsch.ChannelExec;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.JSchException;
import com.jcraft.jsch.Session;

public class sshhelp {
  
  public static String exec(String host,String user,String psw,int port,String command){
    String result="";
    Session session =null;
    ChannelExec openChannel =null;
    try {
      JSch jsch=new JSch();
      session = jsch.getSession(user, host, port);
      Properties config = new Properties();
      config.put("StrictHostKeyChecking", "no");
      session.setConfig(config);
      session.setPassword(psw);
      session.connect();
      openChannel = (ChannelExec) session.openChannel("exec");
      openChannel.setCommand(command);
      int exitStatus = openChannel.getExitStatus();
      System.out.println(exitStatus);
      openChannel.connect();  
            InputStream in = openChannel.getInputStream();  
            BufferedReader reader = new BufferedReader(new InputStreamReader(in));  
            String buf = null;
            while ((buf = reader.readLine()) != null) {
            	result+= new String(buf.getBytes("gbk"),"UTF-8")+"    
\r\n";  
            }  
    } catch (JSchException | IOException e) {
      result+=e.getMessage();
    }finally{
      if(openChannel!=null&&!openChannel.isClosed()){
        openChannel.disconnect();
      }
      if(session!=null&&session.isConnected()){
        session.disconnect();
      }
    }
    return result;
  }
  
  
  
  public static void main(String args[]){
    String exec = exec("you ip add", "root", "root", 22, "sleep 20;ls;");
    System.out.println(exec);	
  }
}

这个包的问题就是线程不能中断，程序一直在运行，那样的话，我们的任务就无法提交上去，因此也选择了放弃这个包，

----------------------------------------------------------------------

最后，我们选择了trilead-ssh2-build13.jar.

这个包虽然不是最好的，但是是最合适的，功能简单，一条命令，不能读取linux的环境变量，但是，完全符合我们的需要

实例代码如下：

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

import com.trilead.ssh2.Connection;
import com.trilead.ssh2.Session;
import com.trilead.ssh2.StreamGobbler;

/**
 * This example shows how to consume stdout/stderr output
 * using two StreamGobblers. This is simpler to program
 * than the state machine approach (see SingleThreadStdoutStderr.java),
 * but you cannot control the amount of memory that is
 * consumed by your application (i.e., in case the other
 * side sends you lots of data).
 * 
 * @author Christian Plattner, [email protected]
 * @version $Id: StdoutAndStderr.java,v 1.2 2007/10/15 12:49:57 cplattne Exp $
 */
public class StdoutAndStderr
{
	public static void main(String[] args)
	{
		String hostname = "you ip addr";
		String username = "root";
		String password = "root";
		String a=("cd; );

		try
		{
			/* Create a connection instance */

			Connection conn = new Connection(hostname);

			/* Now connect */

			conn.connect();

			/* Authenticate */

			boolean isAuthenticated = conn.authenticateWithPassword(username, password);

			if (isAuthenticated == false)
				throw new IOException("Authentication failed.");

			/* Create a session */

			Session sess = conn.openSession();

//			sess.execCommand("echo \"Text on STDOUT\"; echo \"Text on STDERR\" >&2");
			sess.execCommand(a);
			InputStream stdout = new StreamGobbler(sess.getStdout());
			InputStream stderr = new StreamGobbler(sess.getStderr());

			BufferedReader stdoutReader = new BufferedReader(new InputStreamReader(stdout));
			BufferedReader stderrReader = new BufferedReader(new InputStreamReader(stderr));

			//System.out.println("Here is the output from stdout:");

			while (true)
			{
				String line = stdoutReader.readLine();
				if (line == null)
					break;
				System.out.println(line);
			}

			//System.out.println("Here is the output from stderr:");

			while (true)
			{
				String line = stderrReader.readLine();
				if (line == null)
					break;
				System.out.println(line);
			}

			/* Close this session */

			sess.close();

			/* Close the connection */

			conn.close();

		}
		catch (IOException e)
		{
			e.printStackTrace(System.err);
			System.exit(2);
		}
	}
}