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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.unix;
19  
20  import java.io.IOException;
21  import org.apache.commons.net.bsd.RExecClient;
22  
23  import examples.util.IOUtil;
24  
25  /***
26   * This is an example program demonstrating how to use the RExecClient class.
27   * This program connects to an rexec server and requests that the
28   * given command be executed on the server.  It then reads input from stdin
29   * (this will be line buffered on most systems, so don't expect character
30   * at a time interactivity), passing it to the remote process and writes
31   * the process stdout and stderr to local stdout.
32   * <p>
33   * Example: java rexec myhost myusername mypassword "ps -aux"
34   * <p>
35   * Usage: rexec <hostname> <username> <password> <command>
36   * <p>
37   ***/
38  
39  // This class requires the IOUtil support class!
40  public final class rexec
41  {
42  
43      public static void main(String[] args)
44      {
45          String server, username, password, command;
46          RExecClient client;
47  
48          if (args.length != 4)
49          {
50              System.err.println(
51                  "Usage: rexec <hostname> <username> <password> <command>");
52              System.exit(1);
53              return ; // so compiler can do proper flow control analysis
54          }
55  
56          client = new RExecClient();
57  
58          server = args[0];
59          username = args[1];
60          password = args[2];
61          command = args[3];
62  
63          try
64          {
65              client.connect(server);
66          }
67          catch (IOException e)
68          {
69              System.err.println("Could not connect to server.");
70              e.printStackTrace();
71              System.exit(1);
72          }
73  
74          try
75          {
76              client.rexec(username, password, command);
77          }
78          catch (IOException e)
79          {
80              try
81              {
82                  client.disconnect();
83              }
84              catch (IOException f)
85              {}
86              e.printStackTrace();
87              System.err.println("Could not execute command.");
88              System.exit(1);
89          }
90  
91  
92          IOUtil.readWrite(client.getInputStream(), client.getOutputStream(),
93                           System.in, System.out);
94  
95          try
96          {
97              client.disconnect();
98          }
99          catch (IOException e)
100         {
101             e.printStackTrace();
102             System.exit(1);
103         }
104 
105         System.exit(0);
106     }
107 
108 }
109