CorbaORB


1   /*
2   * JBoss, Home of Professional Open Source
3   * Copyright 2005, JBoss Inc., and individual contributors as indicated
4   * by the @authors tag. See the copyright.txt in the distribution for a
5   * full listing of individual contributors.
6   *
7   * This is free software; you can redistribute it and/or modify it
8   * under the terms of the GNU Lesser General Public License as
9   * published by the Free Software Foundation; either version 2.1 of
10  * the License, or (at your option) any later version.
11  *
12  * This software is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with this software; if not, write to the Free
19  * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20  * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
21  */
22  package org.jboss.iiop;
23  
24  import javax.naming.InitialContext  ;
25  
26  import org.jboss.corba.ORBFactory;
27  import org.omg.CORBA.ORB  ;
28  
29  /**
30   * Singleton class to ensure that all code running in the JBoss VM uses the 
31   * same ORB instance. The CorbaORBService MBean calls CorbaORB.setInstance()
32   * at service creation time, after it creates an ORB instance. Code that runs
33   * both in the server VM and in client VM calls CorbaORB.getInstance() to get 
34   * an ORB.
35   *
36   * @author  <a HREF="mailto:reverbel@ime.usp.br">Francisco Reverbel</a>
37   * @version $Revision: 37459 $
38   */
39  public class CorbaORB
40  {
41     /** The ORB instance in this VM. */
42     private static ORB   instance;
43  
44     /** Enforce non-instantiability. */
45     private CorbaORB()
46     {
47     }
48     
49     /** 
50      * This method is called only by the CorbaORBService MBean, so it has
51      * package visibility. 
52      */
53     static void setInstance(ORB   orb)
54     {
55        if (instance == null)
56           instance = orb;
57        else
58           throw new RuntimeException  (CorbaORB.class.getName() 
59                                      + ".setInstance() called more than once");
60     }
61     
62     /**
63      * This method is called by classes that are used both at the server and at 
64      * the client side: the handle impl (org.jboss.proxy.ejb.HandleImplIIOP),
65      * the home handle impl (org.jboss.proxy.ejb.HomeHandleImplIIOP),
66      * and the home factory (org.jboss.proxy.ejb.IIOPHomeFactory).
67      * When called by code running in the same VM as the the JBoss server,
68      * getInstance() returns the ORB instance used by the CorbaORBService MBean 
69      * (which previously issued a setInstance() call). Otherwise getInstance() 
70      * returns an ORB instance obtained with an ORB.init() call.
71      */
72     public static ORB   getInstance() 
73     {
74        // No instance established, we must be on the client
75        // Use the orb consistent with java:comp/ORB (if any).
76        if (instance == null) 
77        {
78           try
79           {
80              InitialContext   ctx = new InitialContext  ();
81              ORB   orb = (ORB  ) ctx.lookup("java:comp/ORB");
82           }
83           catch (Exception   ignored)
84           {
85           }
86           if (instance == null)
87              instance = ORBFactory.getORB();
88        }
89        return instance;
90     }
91  }
92
A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame
Popular Tags