SSH Exec (Execute Command Line)

Shows how to execute a command on an SSH server and retrieve the command output.

Download Chilkat Java Library

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    //  Important: It is helpful to send the contents of the
    //  ssh.LastErrorText property when requesting support.

    CkSsh ssh = new CkSsh();

    //  Any string automatically begins a fully-functional 30-day trial.
    boolean success;
    success = ssh.UnlockComponent("Anything for 30-day trial");
    if (success != true) {
        System.out.println(ssh.lastErrorText());
        return;
    }

    //  Connect to an SSH server:
    String hostname;
    int port;

    //  Hostname may be an IP address or hostname:
    hostname = "192.168.1.108";
    port = 22;

    success = ssh.Connect(hostname,port);
    if (success != true) {
        System.out.println(ssh.lastErrorText());
        return;
    }

    //  Wait a max of 5 seconds when reading responses..
    ssh.put_IdleTimeoutMs(5000);

    //  Authenticate using login/password:
    success = ssh.AuthenticatePw("myLogin","myPassword");
    if (success != true) {
        System.out.println(ssh.lastErrorText());
        return;
    }

    //  Open a session channel.  (It is possible to have multiple
    //  session channels open simultaneously.)
    int channelNum;
    channelNum = ssh.OpenSessionChannel();
    if (channelNum < 0) {
        System.out.println(ssh.lastErrorText());
        return;
    }

    //  The SendReqExec method starts a command on the remote
    //  server.   The syntax of the command string depends on the
    //  default shell used on the remote server to run the command.
    //  On Windows systems it is CMD.EXE.  On UNIX/Linux
    //  systems the user's default shell is typically defined in /etc/password.

    //  Here are some examples of command lines for <b>Windows SSH servers</b>:

    //  Get a directory listing:
    String cmd1;
    cmd1 = "dir";

    //  Do a nameserver lookup:
    String cmd2;
    cmd2 = "nslookup chilkatsoft.com";

    //  List a specific directory.  Given that the shell is CMD.EXE, backslashes must
    //  be used:
    String cmd3;
    cmd3 = "dir \\temp";

    //  Execute a sequence of commands.  The syntax for CMD.EXE may be found
    //  here: http://technet.microsoft.com/en-us/library/bb490880.aspx.  Notice how the commands
    //  are separated by "##" and the entire command must be enclosed in quotes:
    String cmd4;
    cmd4 = "\"cd \\temp&&dir\"";

    //  Here are two examples of command lines for <b>Linux/UNIX SSH servers</b>:

    //  Get a directory listing:
    String cmd5;
    cmd5 = "ls -l /tmp";

    //  Run a series of commands (syntax may depend on your default shell):
    String cmd6;
    cmd6 = "cd /etc; ls -la";

    //  Request a directory listing on the remote server:
    //  If your server is Linux/UNIX, change the string from "dir" to "ls"
    success = ssh.SendReqExec(channelNum,"dir");
    if (success != true) {
        System.out.println(ssh.lastErrorText());
        return;
    }

    //  Read whatever output may already be available on the
    //  SSH connection.  ChannelReadAndPoll returns the number of bytes
    //  that are available in the channel's internal buffer that
    //  are ready to be "picked up" by calling GetReceivedText
    //  or GetReceivedData.
    //  A return value of -1 indicates failure.
    //  A return value of -2 indicates a failure via timeout.

    //  The ChannelReadAndPoll method waits
    //  for data to arrive on the connection usingi the IdleTimeoutMs
    //  property setting.  Once the first data arrives, it continues
    //  reading but instead uses the pollTimeoutMs passed in the 2nd argument:
    //  A return value of -2 indicates a timeout where no data is received.
    int n;
    int pollTimeoutMs;
    pollTimeoutMs = 2000;
    n = ssh.ChannelReadAndPoll(channelNum,pollTimeoutMs);
    if (n < 0) {
        System.out.println(ssh.lastErrorText());
        return;
    }

    //  Close the channel:
    success = ssh.ChannelSendClose(channelNum);
    if (success != true) {
        System.out.println(ssh.lastErrorText());
        return;
    }

    //  Perhaps we did not receive all of the commands output.
    //  To make sure,  call ChannelReceiveToClose to accumulate any remaining
    //  output until the server's corresponding "channel close" is received.
    success = ssh.ChannelReceiveToClose(channelNum);
    if (success != true) {
        System.out.println(ssh.lastErrorText());
        return;
    }

    //  Let's pickup the accumulated output of the command:
    String cmdOutput;
    cmdOutput = ssh.getReceivedText(channelNum,"ansi");
    if (cmdOutput == null ) {
        System.out.println(ssh.lastErrorText());
        return;
    }

    //  Display the remote shell's command output:
    System.out.println(cmdOutput);

    //  Disconnect
    ssh.Disconnect();
  }
}