src/share/classes/javax/rmi/PortableRemoteObject.java

Wed, 26 Feb 2014 14:43:56 -0800

author
katleman
date
Wed, 26 Feb 2014 14:43:56 -0800
changeset 589
abe5b0157c36
parent 553
5ca1b4c282b8
child 748
6845b95cba6b
permissions
-rw-r--r--

Added tag jdk8u20-b03 for changeset 9059a1c85704

     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  * Licensed Materials - Property of IBM
    27  * RMI-IIOP v1.0
    28  * Copyright IBM Corp. 1998 1999  All Rights Reserved
    29  *
    30  */
    32 package javax.rmi;
    34 import java.lang.reflect.Method ;
    36 import org.omg.CORBA.INITIALIZE;
    37 import javax.rmi.CORBA.Util;
    39 import java.rmi.RemoteException;
    40 import java.rmi.NoSuchObjectException;
    41 import java.rmi.Remote;
    42 import java.io.File;
    43 import java.io.FileInputStream;
    44 import java.util.Properties;
    45 import java.net.MalformedURLException ;
    46 import java.security.AccessController;
    47 import java.security.PrivilegedAction;
    48 import java.rmi.server.RMIClassLoader;
    50 import com.sun.corba.se.impl.orbutil.GetPropertyAction;
    52 /**
    53  * Server implementation objects may either inherit from
    54  * javax.rmi.PortableRemoteObject or they may implement a remote interface
    55  * and then use the exportObject method to register themselves as a server object.
    56  * The toStub method takes a server implementation and returns a stub that
    57  * can be used to access that server object.
    58  * The connect method makes a Remote object ready for remote communication.
    59  * The unexportObject method is used to deregister a server object, allowing it to become
    60  * available for garbage collection.
    61  * The narrow method takes an object reference or abstract interface type and
    62  * attempts to narrow it to conform to
    63  * the given interface. If the operation is successful the result will be an
    64  * object of the specified type, otherwise an exception will be thrown.
    65  */
    66 public class PortableRemoteObject {
    68     private static final javax.rmi.CORBA.PortableRemoteObjectDelegate proDelegate;
    70     private static final String PortableRemoteObjectClassKey =
    71             "javax.rmi.CORBA.PortableRemoteObjectClass";
    73     static {
    74         proDelegate = (javax.rmi.CORBA.PortableRemoteObjectDelegate)
    75             createDelegate(PortableRemoteObjectClassKey);
    76     }
    78     /**
    79      * Initializes the object by calling <code>exportObject(this)</code>.
    80      * @exception RemoteException if export fails.
    81      */
    82     protected PortableRemoteObject() throws RemoteException {
    83         if (proDelegate != null) {
    84             PortableRemoteObject.exportObject((Remote)this);
    85         }
    86     }
    88     /**
    89      * Makes a server object ready to receive remote calls. Note
    90      * that subclasses of PortableRemoteObject do not need to call this
    91      * method, as it is called by the constructor.
    92      * @param obj the server object to export.
    93      * @exception RemoteException if export fails.
    94      */
    95     public static void exportObject(Remote obj)
    96         throws RemoteException {
    98         // Let the delegate do everything, including error handling.
    99         if (proDelegate != null) {
   100             proDelegate.exportObject(obj);
   101         }
   102     }
   104     /**
   105      * Returns a stub for the given server object.
   106      * @param obj the server object for which a stub is required. Must either be a subclass
   107      * of PortableRemoteObject or have been previously the target of a call to
   108      * {@link #exportObject}.
   109      * @return the most derived stub for the object.
   110      * @exception NoSuchObjectException if a stub cannot be located for the given server object.
   111      */
   112     public static Remote toStub (Remote obj)
   113         throws NoSuchObjectException {
   115         if (proDelegate != null) {
   116             return proDelegate.toStub(obj);
   117         }
   118         return null;
   119     }
   121     /**
   122      * Deregisters a server object from the runtime, allowing the object to become
   123      * available for garbage collection.
   124      * @param obj the object to unexport.
   125      * @exception NoSuchObjectException if the remote object is not
   126      * currently exported.
   127      */
   128     public static void unexportObject(Remote obj)
   129         throws NoSuchObjectException {
   131         if (proDelegate != null) {
   132             proDelegate.unexportObject(obj);
   133         }
   135     }
   137     /**
   138      * Checks to ensure that an object of a remote or abstract interface type
   139      * can be cast to a desired type.
   140      * @param narrowFrom the object to check.
   141      * @param narrowTo the desired type.
   142      * @return an object which can be cast to the desired type.
   143      * @throws ClassCastException if narrowFrom cannot be cast to narrowTo.
   144      */
   145     public static java.lang.Object narrow ( java.lang.Object narrowFrom,
   146                                             java.lang.Class narrowTo)
   147         throws ClassCastException {
   149         if (proDelegate != null) {
   150             return proDelegate.narrow(narrowFrom, narrowTo);
   151         }
   152         return null;
   154     }
   156     /**
   157      * Makes a Remote object ready for remote communication. This normally
   158      * happens implicitly when the object is sent or received as an argument
   159      * on a remote method call, but in some circumstances it is useful to
   160      * perform this action by making an explicit call.  See the
   161      * {@link javax.rmi.CORBA.Stub#connect} method for more information.
   162      * @param target the object to connect.
   163      * @param source a previously connected object.
   164      * @throws RemoteException if <code>source</code> is not connected
   165      * or if <code>target</code> is already connected to a different ORB than
   166      * <code>source</code>.
   167      */
   168     public static void connect (Remote target, Remote source)
   169         throws RemoteException {
   171         if (proDelegate != null) {
   172             proDelegate.connect(target, source);
   173         }
   175     }
   177     // Same code as in javax.rmi.CORBA.Util. Can not be shared because they
   178     // are in different packages and the visibility needs to be package for
   179     // security reasons. If you know a better solution how to share this code
   180     // then remove it from here.
   181     private static Object createDelegate(String classKey) {
   182         String className = (String)
   183             AccessController.doPrivileged(new GetPropertyAction(classKey));
   184         if (className == null) {
   185             Properties props = getORBPropertiesFile();
   186             if (props != null) {
   187                 className = props.getProperty(classKey);
   188             }
   189         }
   190         if (className == null) {
   191             return new com.sun.corba.se.impl.javax.rmi.PortableRemoteObject();
   192         }
   194         try {
   195             return (Object) loadDelegateClass(className).newInstance();
   196         } catch (ClassNotFoundException ex) {
   197             INITIALIZE exc = new INITIALIZE( "Cannot instantiate " + className);
   198             exc.initCause( ex ) ;
   199             throw exc ;
   200         } catch (Exception ex) {
   201             INITIALIZE exc = new INITIALIZE( "Error while instantiating" + className);
   202             exc.initCause( ex ) ;
   203             throw exc ;
   204         }
   206     }
   208     private static Class loadDelegateClass( String className )  throws ClassNotFoundException
   209     {
   210         try {
   211             ClassLoader loader = Thread.currentThread().getContextClassLoader();
   212             return Class.forName(className, false, loader);
   213         } catch (ClassNotFoundException e) {
   214             // ignore, then try RMIClassLoader
   215         }
   217         try {
   218             return RMIClassLoader.loadClass(className);
   219         } catch (MalformedURLException e) {
   220             String msg = "Could not load " + className + ": " + e.toString();
   221             ClassNotFoundException exc = new ClassNotFoundException( msg ) ;
   222             throw exc ;
   223         }
   224     }
   226     /**
   227      * Load the orb.properties file.
   228      */
   229     private static Properties getORBPropertiesFile () {
   230         return (Properties) AccessController.doPrivileged(new GetORBPropertiesFileAction());
   231     }
   232 }
   234 class GetORBPropertiesFileAction implements PrivilegedAction {
   235     private boolean debug = false ;
   237     public GetORBPropertiesFileAction () {
   238     }
   240     private String getSystemProperty(final String name) {
   241         // This will not throw a SecurityException because this
   242         // class was loaded from rt.jar using the bootstrap classloader.
   243         String propValue = (String) AccessController.doPrivileged(
   244             new PrivilegedAction() {
   245                 public java.lang.Object run() {
   246                     return System.getProperty(name);
   247                 }
   248             }
   249         );
   251         return propValue;
   252     }
   254     private void getPropertiesFromFile( Properties props, String fileName )
   255     {
   256         try {
   257             File file = new File( fileName ) ;
   258             if (!file.exists())
   259                 return ;
   261             FileInputStream in = new FileInputStream( file ) ;
   263             try {
   264                 props.load( in ) ;
   265             } finally {
   266                 in.close() ;
   267             }
   268         } catch (Exception exc) {
   269             if (debug)
   270                 System.out.println( "ORB properties file " + fileName +
   271                     " not found: " + exc) ;
   272         }
   273     }
   275     public Object run()
   276     {
   277         Properties defaults = new Properties() ;
   279         String javaHome = getSystemProperty( "java.home" ) ;
   280         String fileName = javaHome + File.separator + "lib" + File.separator +
   281             "orb.properties" ;
   283         getPropertiesFromFile( defaults, fileName ) ;
   285         Properties results = new Properties( defaults ) ;
   287         String userHome = getSystemProperty( "user.home" ) ;
   288         fileName = userHome + File.separator + "orb.properties" ;
   290         getPropertiesFromFile( results, fileName ) ;
   291         return results ;
   292     }
   293 }

mercurial