KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > examples > rshell


1 /*
2  * Copyright 2001-2005 The Apache Software Foundation
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 package examples;
17
18 import java.io.IOException JavaDoc;
19 import org.apache.commons.net.bsd.RCommandClient;
20
21 /***
22  * This is an example program demonstrating how to use the RCommandClient
23  * class. This program connects to an rshell daemon and requests that the
24  * given command be executed on the server. It then reads input from stdin
25  * (this will be line buffered on most systems, so don't expect character
26  * at a time interactivity), passing it to the remote process and writes
27  * the process stdout and stderr to local stdout.
28  * <p>
29  * On Unix systems you will not be able to use the rshell capability
30  * unless the process runs as root since only root can bind port addresses
31  * lower than 1024.
32  * <p>
33  * Example: java rshell myhost localusername remoteusername "ps -aux"
34  * <p>
35  * Usage: rshell <hostname> <localuser> <remoteuser> <command>
36  * <p>
37  ***/
38
39 // This class requires the IOUtil support class!
40 public final class rshell
41 {
42
43     public static final void main(String JavaDoc[] args)
44     {
45         String JavaDoc server, localuser, remoteuser, command;
46         RCommandClient client;
47
48         if (args.length != 4)
49         {
50             System.err.println(
51                 "Usage: rshell <hostname> <localuser> <remoteuser> <command>");
52             System.exit(1);
53             return ; // so compiler can do proper flow control analysis
54 }
55
56         client = new RCommandClient();
57
58         server = args[0];
59         localuser = args[1];
60         remoteuser = args[2];
61         command = args[3];
62
63         try
64         {
65             client.connect(server);
66         }
67         catch (IOException JavaDoc 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.rcommand(localuser, remoteuser, command);
77         }
78         catch (IOException JavaDoc e)
79         {
80             try
81             {
82                 client.disconnect();
83             }
84             catch (IOException JavaDoc 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 JavaDoc e)
100         {
101             e.printStackTrace();
102             System.exit(1);
103         }
104
105         System.exit(0);
106     }
107
108 }
109
110
Popular Tags