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 org.apache.commons.net.examples.unix;
019
020import java.io.IOException;
021
022import org.apache.commons.net.bsd.RExecClient;
023import org.apache.commons.net.examples.util.IOUtil;
024
025/**
026 * 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
027 * 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),
028 * passing it to the remote process and writes the process stdout and stderr to local stdout.
029 * <p>
030 * Example: java rexec myhost myusername mypassword "ps -aux"
031 * <p>
032 * Usage: rexec <hostname> <username> <password> <command>
033 */
034
035// This class requires the IOUtil support class!
036public final class rexec {
037
038    public static void main(final String[] args) {
039        final String server;
040        final String username;
041        final String password;
042        final String command;
043        final RExecClient client;
044
045        if (args.length != 4) {
046            System.err.println("Usage: rexec <hostname> <username> <password> <command>");
047            System.exit(1);
048            return; // so compiler can do proper flow control analysis
049        }
050
051        client = new RExecClient();
052
053        server = args[0];
054        username = args[1];
055        password = args[2];
056        command = args[3];
057
058        try {
059            client.connect(server);
060        } catch (final IOException e) {
061            System.err.println("Could not connect to server.");
062            e.printStackTrace();
063            System.exit(1);
064        }
065
066        try {
067            client.rexec(username, password, command);
068        } catch (final IOException e) {
069            try {
070                client.disconnect();
071            } catch (final IOException f) {
072                /* ignored */}
073            e.printStackTrace();
074            System.err.println("Could not execute command.");
075            System.exit(1);
076        }
077
078        IOUtil.readWrite(client.getInputStream(), client.getOutputStream(), System.in, System.out);
079
080        try {
081            client.disconnect();
082        } catch (final IOException e) {
083            e.printStackTrace();
084            System.exit(1);
085        }
086
087        System.exit(0);
088    }
089
090}