001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package examples.unix;
019
020import java.io.IOException;
021import org.apache.commons.net.bsd.RExecClient;
022
023import examples.util.IOUtil;
024
025/***
026 * This is an example program demonstrating how to use the RExecClient class.
027 * This program connects to an rexec server and requests that the
028 * given command be executed on the server.  It then reads input from stdin
029 * (this will be line buffered on most systems, so don't expect character
030 * at a time interactivity), passing it to the remote process and writes
031 * the process stdout and stderr to local stdout.
032 * <p>
033 * Example: java rexec myhost myusername mypassword "ps -aux"
034 * <p>
035 * Usage: rexec <hostname> <username> <password> <command>
036 ***/
037
038// This class requires the IOUtil support class!
039public final class rexec
040{
041
042    public static void main(String[] args)
043    {
044        String server, username, password, command;
045        RExecClient client;
046
047        if (args.length != 4)
048        {
049            System.err.println(
050                "Usage: rexec <hostname> <username> <password> <command>");
051            System.exit(1);
052            return ; // so compiler can do proper flow control analysis
053        }
054
055        client = new RExecClient();
056
057        server = args[0];
058        username = args[1];
059        password = args[2];
060        command = args[3];
061
062        try
063        {
064            client.connect(server);
065        }
066        catch (IOException e)
067        {
068            System.err.println("Could not connect to server.");
069            e.printStackTrace();
070            System.exit(1);
071        }
072
073        try
074        {
075            client.rexec(username, password, command);
076        }
077        catch (IOException e)
078        {
079            try
080            {
081                client.disconnect();
082            }
083            catch (IOException f)
084            {/* ignored */}
085            e.printStackTrace();
086            System.err.println("Could not execute command.");
087            System.exit(1);
088        }
089
090
091        IOUtil.readWrite(client.getInputStream(), client.getOutputStream(),
092                         System.in, System.out);
093
094        try
095        {
096            client.disconnect();
097        }
098        catch (IOException e)
099        {
100            e.printStackTrace();
101            System.exit(1);
102        }
103
104        System.exit(0);
105    }
106
107}
108