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 * Copyright (c) 1996, 2003, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package java.rmi.registry;

import java.rmi.RemoteException;

import java.rmi.server.ObjID;

import java.rmi.server.RMIClientSocketFactory;

import java.rmi.server.RMIServerSocketFactory;

import java.rmi.server.RemoteRef;

import java.rmi.server.UnicastRemoteObject;

import sun.rmi.registry.RegistryImpl;

import sun.rmi.server.UnicastRef2;

import sun.rmi.server.UnicastRef;

import sun.rmi.server.Util;

import sun.rmi.transport.LiveRef;

import sun.rmi.transport.tcp.TCPEndpoint;

/**

 * <code>LocateRegistry</code> is used to obtain a reference to a bootstrap

 * remote object registry on a particular host (including the local host), or

 * to create a remote object registry that accepts calls on a specific port.

 *

 * <p> Note that a <code>getRegistry</code> call does not actually make a

 * connection to the remote host.  It simply creates a local reference to

 * the remote registry and will succeed even if no registry is running on

 * the remote host.  Therefore, a subsequent method invocation to a remote

 * registry returned as a result of this method may fail.

 *

 * @author  Ann Wollrath

 * @author  Peter Jones

 * @since   1.1

 * @see     java.rmi.registry.Registry

 */

public final class LocateRegistry {

    /**

     * Private constructor to disable public construction.

     */

    private LocateRegistry() {}

    /**

     * Returns a reference to the remote object <code>Registry</code> for

     * the local host on the default registry port of 1099.

     *

     * @return reference (a stub) to the remote object registry

     * @exception RemoteException if the reference could not be created

     * @since 1.1

     */

    public static Registry getRegistry()

        throws RemoteException

    {

        return getRegistry(null, Registry.REGISTRY_PORT);

    }

    /**

     * Returns a reference to the remote object <code>Registry</code> for

     * the local host on the specified <code>port</code>.

     *

     * @param port port on which the registry accepts requests

     * @return reference (a stub) to the remote object registry

     * @exception RemoteException if the reference could not be created

     * @since 1.1

     */

    public static Registry getRegistry(int port)

        throws RemoteException

    {

        return getRegistry(null, port);

    }

    /**

     * Returns a reference to the remote object <code>Registry</code> on the

     * specified <code>host</code> on the default registry port of 1099.  If

     * <code>host</code> is <code>null</code>, the local host is used.

     *

     * @param host host for the remote registry

     * @return reference (a stub) to the remote object registry

     * @exception RemoteException if the reference could not be created

     * @since 1.1

     */

    public static Registry getRegistry(String host)

        throws RemoteException

    {

        return getRegistry(host, Registry.REGISTRY_PORT);

    }

    /**

     * Returns a reference to the remote object <code>Registry</code> on the

     * specified <code>host</code> and <code>port</code>. If <code>host</code>

     * is <code>null</code>, the local host is used.

     *

     * @param host host for the remote registry

     * @param port port on which the registry accepts requests

     * @return reference (a stub) to the remote object registry

     * @exception RemoteException if the reference could not be created

     * @since 1.1

     */

    public static Registry getRegistry(String host, int port)

        throws RemoteException

    {

        return getRegistry(host, port, null);

    }

    /**

     * Returns a locally created remote reference to the remote object

     * <code>Registry</code> on the specified <code>host</code> and

     * <code>port</code>.  Communication with this remote registry will

     * use the supplied <code>RMIClientSocketFactory</code> <code>csf</code>

     * to create <code>Socket</code> connections to the registry on the

     * remote <code>host</code> and <code>port</code>.

     *

     * @param host host for the remote registry

     * @param port port on which the registry accepts requests

     * @param csf  client-side <code>Socket</code> factory used to

     *      make connections to the registry.  If <code>csf</code>

     *      is null, then the default client-side <code>Socket</code>

     *      factory will be used in the registry stub.

     * @return reference (a stub) to the remote registry

     * @exception RemoteException if the reference could not be created

     * @since 1.2

     */

    public static Registry getRegistry(String host, int port,

                                       RMIClientSocketFactory csf)

        throws RemoteException

    {

        Registry registry = null;

        if (port <= 0)

            port = Registry.REGISTRY_PORT;

        if (host == null || host.length() == 0) {

            // If host is blank (as returned by "file:" URL in 1.0.2 used in

            // java.rmi.Naming), try to convert to real local host name so

            // that the RegistryImpl's checkAccess will not fail.

            try {

                host = java.net.InetAddress.getLocalHost().getHostAddress();

            } catch (Exception e) {

                // If that failed, at least try "" (localhost) anyway...

                host = "";

            }

        }

        /*

         * Create a proxy for the registry with the given host, port, and

         * client socket factory.  If the supplied client socket factory is

         * null, then the ref type is a UnicastRef, otherwise the ref type

         * is a UnicastRef2.  If the property

         * java.rmi.server.ignoreStubClasses is true, then the proxy

         * returned is an instance of a dynamic proxy class that implements

         * the Registry interface; otherwise the proxy returned is an

         * instance of the pregenerated stub class for RegistryImpl.

         **/

        LiveRef liveRef =

            new LiveRef(new ObjID(ObjID.REGISTRY_ID),

                        new TCPEndpoint(host, port, csf, null),

                        false);

        RemoteRef ref =

            (csf == null) ? new UnicastRef(liveRef) : new UnicastRef2(liveRef);

        return (Registry) Util.createProxy(RegistryImpl.class, ref, false);

    }

    /**

     * Creates and exports a <code>Registry</code> instance on the local

     * host that accepts requests on the specified <code>port</code>.

     *

     * <p>The <code>Registry</code> instance is exported as if the static

     * {@link UnicastRemoteObject#exportObject(Remote,int)

     * UnicastRemoteObject.exportObject} method is invoked, passing the

     * <code>Registry</code> instance and the specified <code>port</code> as

     * arguments, except that the <code>Registry</code> instance is

     * exported with a well-known object identifier, an {@link ObjID}

     * instance constructed with the value {@link ObjID#REGISTRY_ID}.

     *

     * @param port the port on which the registry accepts requests

     * @return the registry

     * @exception RemoteException if the registry could not be exported

     * @since 1.1

     **/

    public static Registry createRegistry(int port) throws RemoteException {

        return new RegistryImpl(port);

    }

    /**

     * Creates and exports a <code>Registry</code> instance on the local

     * host that uses custom socket factories for communication with that

     * instance.  The registry that is created listens for incoming

     * requests on the given <code>port</code> using a

     * <code>ServerSocket</code> created from the supplied

     * <code>RMIServerSocketFactory</code>.

     *

     * <p>The <code>Registry</code> instance is exported as if

     * the static {@link

     * UnicastRemoteObject#exportObject(Remote,int,RMIClientSocketFactory,RMIServerSocketFactory)

     * UnicastRemoteObject.exportObject} method is invoked, passing the

     * <code>Registry</code> instance, the specified <code>port</code>, the

     * specified <code>RMIClientSocketFactory</code>, and the specified

     * <code>RMIServerSocketFactory</code> as arguments, except that the

     * <code>Registry</code> instance is exported with a well-known object

     * identifier, an {@link ObjID} instance constructed with the value

     * {@link ObjID#REGISTRY_ID}.

     *

     * @param port port on which the registry accepts requests

     * @param csf  client-side <code>Socket</code> factory used to

     *      make connections to the registry

     * @param ssf  server-side <code>ServerSocket</code> factory

     *      used to accept connections to the registry

     * @return the registry

     * @exception RemoteException if the registry could not be exported

     * @since 1.2

     **/

    public static Registry createRegistry(int port,

                                          RMIClientSocketFactory csf,

                                          RMIServerSocketFactory ssf)

        throws RemoteException

    {

        return new RegistryImpl(port, csf, ssf);

    }

}