duke@1: /*
ohair@240:  * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
duke@1:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@1:  *
duke@1:  * This code is free software; you can redistribute it and/or modify it
duke@1:  * under the terms of the GNU General Public License version 2 only, as
ohair@158:  * published by the Free Software Foundation.  Oracle designates this
duke@1:  * particular file as subject to the "Classpath" exception as provided
ohair@158:  * by Oracle in the LICENSE file that accompanied this code.
duke@1:  *
duke@1:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@1:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@1:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@1:  * version 2 for more details (a copy is included in the LICENSE file that
duke@1:  * accompanied this code).
duke@1:  *
duke@1:  * You should have received a copy of the GNU General Public License version
duke@1:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@1:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@1:  *
ohair@158:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
ohair@158:  * or visit www.oracle.com if you need additional information or have any
ohair@158:  * questions.
duke@1:  */
duke@1: /*
duke@1:  * Licensed Materials - Property of IBM
duke@1:  * RMI-IIOP v1.0
duke@1:  * Copyright IBM Corp. 1998 1999  All Rights Reserved
duke@1:  *
duke@1:  */
duke@1: 
duke@1: package javax.rmi;
duke@1: 
duke@1: import java.lang.reflect.Method ;
duke@1: 
duke@1: import org.omg.CORBA.INITIALIZE;
duke@1: import javax.rmi.CORBA.Util;
duke@1: 
duke@1: import java.rmi.RemoteException;
duke@1: import java.rmi.NoSuchObjectException;
duke@1: import java.rmi.Remote;
duke@1: import java.io.File;
duke@1: import java.io.FileInputStream;
duke@1: import java.util.Properties;
duke@1: import java.net.MalformedURLException ;
duke@1: import java.security.AccessController;
duke@1: import java.security.PrivilegedAction;
duke@1: import java.rmi.server.RMIClassLoader;
duke@1: 
duke@1: import com.sun.corba.se.impl.orbutil.GetPropertyAction;
duke@1: 
duke@1: /**
duke@1:  * Server implementation objects may either inherit from
duke@1:  * javax.rmi.PortableRemoteObject or they may implement a remote interface
duke@1:  * and then use the exportObject method to register themselves as a server object.
duke@1:  * The toStub method takes a server implementation and returns a stub that
duke@1:  * can be used to access that server object.
duke@1:  * The connect method makes a Remote object ready for remote communication.
duke@1:  * The unexportObject method is used to deregister a server object, allowing it to become
duke@1:  * available for garbage collection.
duke@1:  * The narrow method takes an object reference or abstract interface type and
duke@1:  * attempts to narrow it to conform to
duke@1:  * the given interface. If the operation is successful the result will be an
duke@1:  * object of the specified type, otherwise an exception will be thrown.
duke@1:  */
duke@1: public class PortableRemoteObject {
duke@1: 
alanb@533:     private static final javax.rmi.CORBA.PortableRemoteObjectDelegate proDelegate;
duke@1: 
duke@1:     private static final String PortableRemoteObjectClassKey =
duke@1:             "javax.rmi.CORBA.PortableRemoteObjectClass";
duke@1: 
duke@1:     static {
duke@1:         proDelegate = (javax.rmi.CORBA.PortableRemoteObjectDelegate)
alanb@533:             createDelegate(PortableRemoteObjectClassKey);
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * Initializes the object by calling <code>exportObject(this)</code>.
duke@1:      * @exception RemoteException if export fails.
duke@1:      */
duke@1:     protected PortableRemoteObject() throws RemoteException {
duke@1:         if (proDelegate != null) {
duke@1:             PortableRemoteObject.exportObject((Remote)this);
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * Makes a server object ready to receive remote calls. Note
duke@1:      * that subclasses of PortableRemoteObject do not need to call this
duke@1:      * method, as it is called by the constructor.
duke@1:      * @param obj the server object to export.
duke@1:      * @exception RemoteException if export fails.
duke@1:      */
duke@1:     public static void exportObject(Remote obj)
duke@1:         throws RemoteException {
duke@1: 
duke@1:         // Let the delegate do everything, including error handling.
duke@1:         if (proDelegate != null) {
duke@1:             proDelegate.exportObject(obj);
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * Returns a stub for the given server object.
duke@1:      * @param obj the server object for which a stub is required. Must either be a subclass
duke@1:      * of PortableRemoteObject or have been previously the target of a call to
duke@1:      * {@link #exportObject}.
duke@1:      * @return the most derived stub for the object.
duke@1:      * @exception NoSuchObjectException if a stub cannot be located for the given server object.
duke@1:      */
duke@1:     public static Remote toStub (Remote obj)
duke@1:         throws NoSuchObjectException {
duke@1: 
duke@1:         if (proDelegate != null) {
duke@1:             return proDelegate.toStub(obj);
duke@1:         }
duke@1:         return null;
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * Deregisters a server object from the runtime, allowing the object to become
duke@1:      * available for garbage collection.
duke@1:      * @param obj the object to unexport.
duke@1:      * @exception NoSuchObjectException if the remote object is not
duke@1:      * currently exported.
duke@1:      */
duke@1:     public static void unexportObject(Remote obj)
duke@1:         throws NoSuchObjectException {
duke@1: 
duke@1:         if (proDelegate != null) {
duke@1:             proDelegate.unexportObject(obj);
duke@1:         }
duke@1: 
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * Checks to ensure that an object of a remote or abstract interface type
duke@1:      * can be cast to a desired type.
duke@1:      * @param narrowFrom the object to check.
duke@1:      * @param narrowTo the desired type.
duke@1:      * @return an object which can be cast to the desired type.
duke@1:      * @throws ClassCastException if narrowFrom cannot be cast to narrowTo.
duke@1:      */
duke@1:     public static java.lang.Object narrow ( java.lang.Object narrowFrom,
duke@1:                                             java.lang.Class narrowTo)
duke@1:         throws ClassCastException {
duke@1: 
duke@1:         if (proDelegate != null) {
duke@1:             return proDelegate.narrow(narrowFrom, narrowTo);
duke@1:         }
duke@1:         return null;
duke@1: 
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * Makes a Remote object ready for remote communication. This normally
duke@1:      * happens implicitly when the object is sent or received as an argument
duke@1:      * on a remote method call, but in some circumstances it is useful to
duke@1:      * perform this action by making an explicit call.  See the
andrew@135:      * {@link javax.rmi.CORBA.Stub#connect} method for more information.
duke@1:      * @param target the object to connect.
duke@1:      * @param source a previously connected object.
duke@1:      * @throws RemoteException if <code>source</code> is not connected
duke@1:      * or if <code>target</code> is already connected to a different ORB than
duke@1:      * <code>source</code>.
duke@1:      */
duke@1:     public static void connect (Remote target, Remote source)
duke@1:         throws RemoteException {
duke@1: 
duke@1:         if (proDelegate != null) {
duke@1:             proDelegate.connect(target, source);
duke@1:         }
duke@1: 
duke@1:     }
duke@1: 
duke@1:     // Same code as in javax.rmi.CORBA.Util. Can not be shared because they
duke@1:     // are in different packages and the visibility needs to be package for
duke@1:     // security reasons. If you know a better solution how to share this code
duke@1:     // then remove it from here.
alanb@533:     private static Object createDelegate(String classKey) {
duke@1:         String className = (String)
duke@1:             AccessController.doPrivileged(new GetPropertyAction(classKey));
duke@1:         if (className == null) {
duke@1:             Properties props = getORBPropertiesFile();
duke@1:             if (props != null) {
duke@1:                 className = props.getProperty(classKey);
duke@1:             }
duke@1:         }
duke@1:         if (className == null) {
alanb@533:             return new com.sun.corba.se.impl.javax.rmi.PortableRemoteObject();
duke@1:         }
duke@1: 
duke@1:         try {
duke@1:             return (Object) loadDelegateClass(className).newInstance();
duke@1:         } catch (ClassNotFoundException ex) {
duke@1:             INITIALIZE exc = new INITIALIZE( "Cannot instantiate " + className);
duke@1:             exc.initCause( ex ) ;
duke@1:             throw exc ;
duke@1:         } catch (Exception ex) {
duke@1:             INITIALIZE exc = new INITIALIZE( "Error while instantiating" + className);
duke@1:             exc.initCause( ex ) ;
duke@1:             throw exc ;
duke@1:         }
duke@1: 
duke@1:     }
duke@1: 
duke@1:     private static Class loadDelegateClass( String className )  throws ClassNotFoundException
duke@1:     {
duke@1:         try {
duke@1:             ClassLoader loader = Thread.currentThread().getContextClassLoader();
duke@1:             return Class.forName(className, false, loader);
duke@1:         } catch (ClassNotFoundException e) {
duke@1:             // ignore, then try RMIClassLoader
duke@1:         }
duke@1: 
duke@1:         try {
duke@1:             return RMIClassLoader.loadClass(className);
duke@1:         } catch (MalformedURLException e) {
duke@1:             String msg = "Could not load " + className + ": " + e.toString();
duke@1:             ClassNotFoundException exc = new ClassNotFoundException( msg ) ;
duke@1:             throw exc ;
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * Load the orb.properties file.
duke@1:      */
duke@1:     private static Properties getORBPropertiesFile () {
duke@1:         return (Properties) AccessController.doPrivileged(new GetORBPropertiesFileAction());
duke@1:     }
duke@1: }
duke@1: 
duke@1: class GetORBPropertiesFileAction implements PrivilegedAction {
duke@1:     private boolean debug = false ;
duke@1: 
duke@1:     public GetORBPropertiesFileAction () {
duke@1:     }
duke@1: 
duke@1:     private String getSystemProperty(final String name) {
duke@1:         // This will not throw a SecurityException because this
duke@1:         // class was loaded from rt.jar using the bootstrap classloader.
duke@1:         String propValue = (String) AccessController.doPrivileged(
duke@1:             new PrivilegedAction() {
duke@1:                 public java.lang.Object run() {
duke@1:                     return System.getProperty(name);
duke@1:                 }
duke@1:             }
duke@1:         );
duke@1: 
duke@1:         return propValue;
duke@1:     }
duke@1: 
duke@1:     private void getPropertiesFromFile( Properties props, String fileName )
duke@1:     {
duke@1:         try {
duke@1:             File file = new File( fileName ) ;
duke@1:             if (!file.exists())
duke@1:                 return ;
duke@1: 
duke@1:             FileInputStream in = new FileInputStream( file ) ;
duke@1: 
duke@1:             try {
duke@1:                 props.load( in ) ;
duke@1:             } finally {
duke@1:                 in.close() ;
duke@1:             }
duke@1:         } catch (Exception exc) {
duke@1:             if (debug)
duke@1:                 System.out.println( "ORB properties file " + fileName +
duke@1:                     " not found: " + exc) ;
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     public Object run()
duke@1:     {
duke@1:         Properties defaults = new Properties() ;
duke@1: 
duke@1:         String javaHome = getSystemProperty( "java.home" ) ;
duke@1:         String fileName = javaHome + File.separator + "lib" + File.separator +
duke@1:             "orb.properties" ;
duke@1: 
duke@1:         getPropertiesFromFile( defaults, fileName ) ;
duke@1: 
duke@1:         Properties results = new Properties( defaults ) ;
duke@1: 
duke@1:         String userHome = getSystemProperty( "user.home" ) ;
duke@1:         fileName = userHome + File.separator + "orb.properties" ;
duke@1: 
duke@1:         getPropertiesFromFile( results, fileName ) ;
duke@1:         return results ;
duke@1:     }
duke@1: }