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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  package examples;
19  
20  import java.io.IOException;
21  import org.apache.commons.net.bsd.RExecClient;
22  
23  /***
24   * This is an example program demonstrating how to use the RExecClient class.
25   * This program connects to an rexec server and requests that the
26   * given command be executed on the server.  It then reads input from stdin
27   * (this will be line buffered on most systems, so don't expect character
28   * at a time interactivity), passing it to the remote process and writes
29   * the process stdout and stderr to local stdout.
30   * <p>
31   * Example: java rexec myhost myusername mypassword "ps -aux"
32   * <p>
33   * Usage: rexec <hostname> <username> <password> <command>
34   * <p>
35   ***/
36  
37  // This class requires the IOUtil support class!
38  public final class rexec
39  {
40  
41      public static final void main(String[] args)
42      {
43          String server, username, password, command;
44          RExecClient client;
45  
46          if (args.length != 4)
47          {
48              System.err.println(
49                  "Usage: rexec <hostname> <username> <password> <command>");
50              System.exit(1);
51              return ; // so compiler can do proper flow control analysis
52          }
53  
54          client = new RExecClient();
55  
56          server = args[0];
57          username = args[1];
58          password = args[2];
59          command = args[3];
60  
61          try
62          {
63              client.connect(server);
64          }
65          catch (IOException e)
66          {
67              System.err.println("Could not connect to server.");
68              e.printStackTrace();
69              System.exit(1);
70          }
71  
72          try
73          {
74              client.rexec(username, password, command);
75          }
76          catch (IOException e)
77          {
78              try
79              {
80                  client.disconnect();
81              }
82              catch (IOException f)
83              {}
84              e.printStackTrace();
85              System.err.println("Could not execute command.");
86              System.exit(1);
87          }
88  
89  
90          IOUtil.readWrite(client.getInputStream(), client.getOutputStream(),
91                           System.in, System.out);
92  
93          try
94          {
95              client.disconnect();
96          }
97          catch (IOException e)
98          {
99              e.printStackTrace();
100             System.exit(1);
101         }
102 
103         System.exit(0);
104     }
105 
106 }
107