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1   /*
2    * Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4    *
5    * This code is free software; you can redistribute it and/or modify it
6    * under the terms of the GNU General Public License version 2 only, as
7    * published by the Free Software Foundation.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14   * version 2 for more details (a copy is included in the LICENSE file that
15   * accompanied this code).
16   *
17   * You should have received a copy of the GNU General Public License version
18   * 2 along with this work; if not, write to the Free Software Foundation,
19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  
26  /*
27   * Licensed Materials - Property of IBM
28   * RMI-IIOP v1.0
29   * Copyright IBM Corp. 1998 1999  All Rights Reserved
30   *
31   */
32  
33  package javax.rmi.CORBA;
34  
35  import org.omg.CORBA.ORB;
36  import org.omg.CORBA.INITIALIZE;
37  import org.omg.CORBA_2_3.portable.ObjectImpl;
38  
39  import java.io.IOException;
40  import java.rmi.RemoteException;
41  import java.io.File;
42  import java.io.FileInputStream;
43  import java.net.MalformedURLException ;
44  import java.security.AccessController;
45  import java.security.PrivilegedAction;
46  import java.util.Properties;
47  import java.rmi.server.RMIClassLoader;
48  
49  import com.sun.corba.se.impl.orbutil.GetPropertyAction;
50  
51  
52  /**
53   * Base class from which all RMI-IIOP stubs must inherit.
54   */
55  public abstract class Stub extends ObjectImpl
56      implements java.io.Serializable {
57  
58      private static final long serialVersionUID = 1087775603798577179L;
59  
60      // This can only be set at object construction time (no sync necessary).
61      private transient StubDelegate stubDelegate = null;
62      private static Class stubDelegateClass = null;
63      private static final String StubClassKey = "javax.rmi.CORBA.StubClass";
64  
65      static {
66          Object stubDelegateInstance = createDelegate(StubClassKey);
67          if (stubDelegateInstance != null)
68              stubDelegateClass = stubDelegateInstance.getClass();
69      }
70  
71  
72      /**
73       * Returns a hash code value for the object which is the same for all stubs
74       * that represent the same remote object.
75       * @return the hash code value.
76       */
77      public int hashCode() {
78  
79          if (stubDelegate == null) {
80              setDefaultDelegate();
81          }
82  
83          if (stubDelegate != null) {
84              return stubDelegate.hashCode(this);
85          }
86  
87          return 0;
88      }
89  
90      /**
91       * Compares two stubs for equality. Returns <code>true</code> when used to compare stubs
92       * that represent the same remote object, and <code>false</code> otherwise.
93       * @param obj the reference object with which to compare.
94       * @return <code>true</code> if this object is the same as the <code>obj</code>
95       *          argument; <code>false</code> otherwise.
96       */
97      public boolean equals(java.lang.Object obj) {
98  
99          if (stubDelegate == null) {
100             setDefaultDelegate();
101         }
102 
103         if (stubDelegate != null) {
104             return stubDelegate.equals(this, obj);
105         }
106 
107         return false;
108     }
109 
110     /**
111      * Returns a string representation of this stub. Returns the same string
112      * for all stubs that represent the same remote object.
113      * @return a string representation of this stub.
114      */
115     public String toString() {
116 
117 
118         if (stubDelegate == null) {
119             setDefaultDelegate();
120         }
121 
122         String ior;
123         if (stubDelegate != null) {
124             ior = stubDelegate.toString(this);
125             if (ior == null) {
126                 return super.toString();
127             } else {
128                 return ior;
129             }
130         }
131         return super.toString();
132     }
133 
134     /**
135      * Connects this stub to an ORB. Required after the stub is deserialized
136      * but not after it is demarshalled by an ORB stream. If an unconnected
137      * stub is passed to an ORB stream for marshalling, it is implicitly
138      * connected to that ORB. Application code should not call this method
139      * directly, but should call the portable wrapper method
140      * {@link javax.rmi.PortableRemoteObject#connect}.
141      * @param orb the ORB to connect to.
142      * @exception RemoteException if the stub is already connected to a different
143      * ORB, or if the stub does not represent an exported remote or local object.
144      */
145     public void connect(ORB orb) throws RemoteException {
146 
147         if (stubDelegate == null) {
148             setDefaultDelegate();
149         }
150 
151         if (stubDelegate != null) {
152             stubDelegate.connect(this, orb);
153         }
154 
155     }
156 
157     /**
158      * Serialization method to restore the IOR state.
159      */
160     private void readObject(java.io.ObjectInputStream stream)
161         throws IOException, ClassNotFoundException {
162 
163         if (stubDelegate == null) {
164             setDefaultDelegate();
165         }
166 
167         if (stubDelegate != null) {
168             stubDelegate.readObject(this, stream);
169         }
170 
171     }
172 
173     /**
174      * Serialization method to save the IOR state.
175      * @serialData The length of the IOR type ID (int), followed by the IOR type ID
176      * (byte array encoded using ISO8859-1), followed by the number of IOR profiles
177      * (int), followed by the IOR profiles.  Each IOR profile is written as a
178      * profile tag (int), followed by the length of the profile data (int), followed
179      * by the profile data (byte array).
180      */
181     private void writeObject(java.io.ObjectOutputStream stream) throws IOException {
182 
183         if (stubDelegate == null) {
184             setDefaultDelegate();
185         }
186 
187         if (stubDelegate != null) {
188             stubDelegate.writeObject(this, stream);
189         }
190     }
191 
192     private void setDefaultDelegate() {
193         if (stubDelegateClass != null) {
194             try {
195                  stubDelegate = (javax.rmi.CORBA.StubDelegate) stubDelegateClass.newInstance();
196             } catch (Exception ex) {
197             // what kind of exception to throw
198             // delegate not set therefore it is null and will return default
199             // values
200             }
201         }
202     }
203 
204     // Same code as in PortableRemoteObject. Can not be shared because they
205     // are in different packages and the visibility needs to be package for
206     // security reasons. If you know a better solution how to share this code
207     // then remove it from PortableRemoteObject. Also in Util.java
208     private static Object createDelegate(String classKey) {
209         String className = (String)
210             AccessController.doPrivileged(new GetPropertyAction(classKey));
211         if (className == null) {
212             Properties props = getORBPropertiesFile();
213             if (props != null) {
214                 className = props.getProperty(classKey);
215             }
216         }
217 
218         if (className == null) {
219             return new com.sun.corba.se.impl.javax.rmi.CORBA.StubDelegateImpl();
220         }
221 
222         try {
223             return loadDelegateClass(className).newInstance();
224         } catch (ClassNotFoundException ex) {
225             INITIALIZE exc = new INITIALIZE( "Cannot instantiate " + className);
226             exc.initCause( ex ) ;
227             throw exc ;
228         } catch (Exception ex) {
229             INITIALIZE exc = new INITIALIZE( "Error while instantiating" + className);
230             exc.initCause( ex ) ;
231             throw exc ;
232         }
233 
234     }
235 
236     private static Class loadDelegateClass( String className )  throws ClassNotFoundException
237     {
238         try {
239             ClassLoader loader = Thread.currentThread().getContextClassLoader();
240             return Class.forName(className, false, loader);
241         } catch (ClassNotFoundException e) {
242             // ignore, then try RMIClassLoader
243         }
244 
245         try {
246             return RMIClassLoader.loadClass(className);
247         } catch (MalformedURLException e) {
248             String msg = "Could not load " + className + ": " + e.toString();
249             ClassNotFoundException exc = new ClassNotFoundException( msg ) ;
250             throw exc ;
251         }
252     }
253 
254     /**
255      * Load the orb.properties file.
256      */
257     private static Properties getORBPropertiesFile () {
258         return (Properties) AccessController.doPrivileged(new GetORBPropertiesFileAction());
259     }
260 
261 }