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 myuser 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
040        if (args.length != 4) {
041            System.err.println("Usage: rexec <hostname> <user> <password> <command>");
042            System.exit(1);
043            return; // so compiler can do proper flow control analysis
044        }
045
046        final RExecClient client = new RExecClient();
047        final String server = args[0];
048        final String user = args[1];
049        final String password = args[2];
050        final String command = args[3];
051
052        try {
053            client.connect(server);
054        } catch (final IOException e) {
055            System.err.println("Could not connect to server.");
056            e.printStackTrace();
057            System.exit(1);
058        }
059
060        try {
061            client.rexec(user, password, command);
062        } catch (final IOException e) {
063            try {
064                client.disconnect();
065            } catch (final IOException f) {
066                /* ignored */
067            }
068            e.printStackTrace();
069            System.err.println("Could not execute command.");
070            System.exit(1);
071        }
072
073        IOUtil.readWrite(client.getInputStream(), client.getOutputStream(), System.in, System.out);
074
075        try {
076            client.disconnect();
077        } catch (final IOException e) {
078            e.printStackTrace();
079            System.exit(1);
080        }
081
082        System.exit(0);
083    }
084
085}