1 /*

     2  * Copyright (c) 2009, 2012, 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 package com.sun.jmx.remote.internal;

    27 

    28 import java.util.Properties;

    29 import java.io.IOException;

    30 import java.rmi.Remote;

    31 import java.rmi.NoSuchObjectException;

    32 

    33 import java.security.AccessController;

    34 import java.security.PrivilegedAction;

    35 

    36 /**

    37  * A helper class for RMI-IIOP and CORBA APIs.

    38  */

    39 

    40 public final class IIOPHelper {

    41     private IIOPHelper() { }

    42 

    43     // loads IIOPProxy implementation class if available

    44     private static final String IMPL_CLASS =

    45         "com.sun.jmx.remote.protocol.iiop.IIOPProxyImpl";

    46     private static final IIOPProxy proxy =

    47         AccessController.doPrivileged(new PrivilegedAction<IIOPProxy>() {

    48             public IIOPProxy run() {

    49                 try {

    50                     Class<?> c = Class.forName(IMPL_CLASS, true,

    51                                                IIOPHelper.class.getClassLoader());

    52                     return (IIOPProxy)c.newInstance();

    53                 } catch (ClassNotFoundException cnf) {

    54                     return null;

    55                 } catch (InstantiationException e) {

    56                     throw new AssertionError(e);

    57                 } catch (IllegalAccessException e) {

    58                     throw new AssertionError(e);

    59                 }

    60             }});

    61 

    62     /**

    63      * Returns true if RMI-IIOP and CORBA is available.

    64      */

    65     public static boolean isAvailable() {

    66         return proxy != null;

    67     }

    68 

    69     private static void ensureAvailable() {

    70         if (proxy == null)

    71             throw new AssertionError("Should not here");

    72     }

    73 

    74     /**

    75      * Returns true if the given object is a Stub.

    76      */

    77     public static boolean isStub(Object obj) {

    78         return (proxy == null) ? false : proxy.isStub(obj);

    79     }

    80 

    81     /**

    82      * Returns the Delegate to which the given Stub delegates.

    83      */

    84     public static Object getDelegate(Object stub) {

    85         ensureAvailable();

    86         return proxy.getDelegate(stub);

    87     }

    88 

    89     /**

    90      * Sets the Delegate for a given Stub.

    91      */

    92     public static void setDelegate(Object stub, Object delegate) {

    93         ensureAvailable();

    94         proxy.setDelegate(stub, delegate);

    95     }

    96 

    97     /**

    98      * Returns the ORB associated with the given stub

    99      *

   100      * @throws  UnsupportedOperationException

   101      *          if the object does not support the operation that

   102      *          was invoked

   103      */

   104     public static Object getOrb(Object stub) {

   105         ensureAvailable();

   106         return proxy.getOrb(stub);

   107     }

   108 

   109     /**

   110      * Connects the Stub to the given ORB.

   111      */

   112     public static void connect(Object stub, Object orb)

   113         throws IOException

   114     {

   115         if (proxy == null)

   116             throw new IOException("Connection to ORB failed, RMI/IIOP not available");

   117         proxy.connect(stub, orb);

   118     }

   119 

   120     /**

   121      * Returns true if the given object is an ORB.

   122      */

   123     public static boolean isOrb(Object obj) {

   124         return (proxy == null) ? false : proxy.isOrb(obj);

   125     }

   126 

   127     /**

   128      * Creates, and returns, a new ORB instance.

   129      */

   130     public static Object createOrb(String[] args, Properties props)

   131         throws IOException

   132     {

   133         if (proxy == null)

   134             throw new IOException("ORB initialization failed, RMI/IIOP not available");

   135         return proxy.createOrb(args, props);

   136     }

   137 

   138     /**

   139      * Converts a string, produced by the object_to_string method, back

   140      * to a CORBA object reference.

   141      */

   142     public static Object stringToObject(Object orb, String str) {

   143         ensureAvailable();

   144         return proxy.stringToObject(orb, str);

   145     }

   146 

   147     /**

   148      * Converts the given CORBA object reference to a string.

   149      */

   150     public static String objectToString(Object orb, Object obj) {

   151         ensureAvailable();

   152         return proxy.objectToString(orb, obj);

   153     }

   154 

   155     /**

   156      * Checks to ensure that an object of a remote or abstract interface

   157      * type can be cast to a desired type.

   158      */

   159     public static <T> T narrow(Object narrowFrom, Class<T> narrowTo) {

   160         ensureAvailable();

   161         return proxy.narrow(narrowFrom, narrowTo);

   162     }

   163 

   164     /**

   165      * Makes a server object ready to receive remote calls

   166      */

   167     public static void exportObject(Remote obj) throws IOException {

   168         if (proxy == null)

   169             throw new IOException("RMI object cannot be exported, RMI/IIOP not available");

   170         proxy.exportObject(obj);

   171     }

   172 

   173     /**

   174      * Deregisters a server object from the runtime.

   175      */

   176     public static void unexportObject(Remote obj) throws IOException {

   177         if (proxy == null)

   178             throw new NoSuchObjectException("Object not exported");

   179         proxy.unexportObject(obj);

   180     }

   181 

   182     /**

   183      * Returns a stub for the given server object.

   184      */

   185     public static Remote toStub(Remote obj) throws IOException {

   186         if (proxy == null)

   187             throw new NoSuchObjectException("Object not exported");

   188         return proxy.toStub(obj);

   189     }

   190 }