src/java/examples/rexec.java

package examples;

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import java.io.IOException;
import org.apache.commons.net.bsd.RExecClient;

/***
 * This is an example program demonstrating how to use the RExecClient class.
 * This program connects to an rexec server and requests that the
 * given command be executed on the server.  It then reads input from stdin
 * (this will be line buffered on most systems, so don't expect character
 * at a time interactivity), passing it to the remote process and writes
 * the process stdout and stderr to local stdout.
 * <p>
 * Example: java rexec myhost myusername mypassword "ps -aux"
 * <p>
 * Usage: rexec <hostname> <username> <password> <command>
 * <p>
 ***/

// This class requires the IOUtil support class!
public final class rexec
{

    public static final void main(String[] args)
    {
        String server, username, password, command;
        RExecClient client;

        if (args.length != 4)
        {
            System.err.println(
                "Usage: rexec <hostname> <username> <password> <command>");
            System.exit(1);
            return ; // so compiler can do proper flow control analysis
        }

        client = new RExecClient();

        server = args[0];
        username = args[1];
        password = args[2];
        command = args[3];

        try
        {
            client.connect(server);
        }
        catch (IOException e)
        {
            System.err.println("Could not connect to server.");
            e.printStackTrace();
            System.exit(1);
        }

        try
        {
            client.rexec(username, password, command);
        }
        catch (IOException e)
        {
            try
            {
                client.disconnect();
            }
            catch (IOException f)
            {}
            e.printStackTrace();
            System.err.println("Could not execute command.");
            System.exit(1);
        }


        IOUtil.readWrite(client.getInputStream(), client.getOutputStream(),
                         System.in, System.out);

        try
        {
            client.disconnect();
        }
        catch (IOException e)
        {
            e.printStackTrace();
            System.exit(1);
        }

        System.exit(0);
    }

}