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

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

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 * 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).

 *

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 *

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package java.rmi.registry;

import java.rmi.AccessException;

import java.rmi.AlreadyBoundException;

import java.rmi.NotBoundException;

import java.rmi.Remote;

import java.rmi.RemoteException;

/**

 * <code>Registry</code> is a remote interface to a simple remote

 * object registry that provides methods for storing and retrieving

 * remote object references bound with arbitrary string names.  The

 * <code>bind</code>, <code>unbind</code>, and <code>rebind</code>

 * methods are used to alter the name bindings in the registry, and

 * the <code>lookup</code> and <code>list</code> methods are used to

 * query the current name bindings.

 *

 * <p>In its typical usage, a <code>Registry</code> enables RMI client

 * bootstrapping: it provides a simple means for a client to obtain an

 * initial reference to a remote object.  Therefore, a registry's

 * remote object implementation is typically exported with a

 * well-known address, such as with a well-known {@link

 * java.rmi.server.ObjID#REGISTRY_ID ObjID} and TCP port number

 * (default is {@link #REGISTRY_PORT 1099}).

 *

 * <p>The {@link LocateRegistry} class provides a programmatic API for

 * constructing a bootstrap reference to a <code>Registry</code> at a

 * remote address (see the static <code>getRegistry</code> methods)

 * and for creating and exporting a <code>Registry</code> in the

 * current VM on a particular local address (see the static

 * <code>createRegistry</code> methods).

 *

 * <p>A <code>Registry</code> implementation may choose to restrict

 * access to some or all of its methods (for example, methods that

 * mutate the registry's bindings may be restricted to calls

 * originating from the local host).  If a <code>Registry</code>

 * method chooses to deny access for a given invocation, its

 * implementation may throw {@link java.rmi.AccessException}, which

 * (because it extends {@link java.rmi.RemoteException}) will be

 * wrapped in a {@link java.rmi.ServerException} when caught by a

 * remote client.

 *

 * <p>The names used for bindings in a <code>Registry</code> are pure

 * strings, not parsed.  A service which stores its remote reference

 * in a <code>Registry</code> may wish to use a package name as a

 * prefix in the name binding to reduce the likelihood of name

 * collisions in the registry.

 *

 * @author      Ann Wollrath

 * @author      Peter Jones

 * @since       1.1

 * @see         LocateRegistry

 */

public interface Registry extends Remote {

    /** Well known port for registry. */

    public static final int REGISTRY_PORT = 1099;

    /**

     * Returns the remote reference bound to the specified

     * <code>name</code> in this registry.

     *

     * @param   name the name for the remote reference to look up

     *

     * @return  a reference to a remote object

     *

     * @throws  NotBoundException if <code>name</code> is not currently bound

     *

     * @throws  RemoteException if remote communication with the

     * registry failed; if exception is a <code>ServerException</code>

     * containing an <code>AccessException</code>, then the registry

     * denies the caller access to perform this operation

     *

     * @throws  AccessException if this registry is local and it denies

     * the caller access to perform this operation

     *

     * @throws  NullPointerException if <code>name</code> is <code>null</code>

     */

    public Remote lookup(String name)

        throws RemoteException, NotBoundException, AccessException;

    /**

     * Binds a remote reference to the specified <code>name</code> in

     * this registry.

     *

     * @param   name the name to associate with the remote reference

     * @param   obj a reference to a remote object (usually a stub)

     *

     * @throws  AlreadyBoundException if <code>name</code> is already bound

     *

     * @throws  RemoteException if remote communication with the

     * registry failed; if exception is a <code>ServerException</code>

     * containing an <code>AccessException</code>, then the registry

     * denies the caller access to perform this operation (if

     * originating from a non-local host, for example)

     *

     * @throws  AccessException if this registry is local and it denies

     * the caller access to perform this operation

     *

     * @throws  NullPointerException if <code>name</code> is

     * <code>null</code>, or if <code>obj</code> is <code>null</code>

     */

    public void bind(String name, Remote obj)

        throws RemoteException, AlreadyBoundException, AccessException;

    /**

     * Removes the binding for the specified <code>name</code> in

     * this registry.

     *

     * @param   name the name of the binding to remove

     *

     * @throws  NotBoundException if <code>name</code> is not currently bound

     *

     * @throws  RemoteException if remote communication with the

     * registry failed; if exception is a <code>ServerException</code>

     * containing an <code>AccessException</code>, then the registry

     * denies the caller access to perform this operation (if

     * originating from a non-local host, for example)

     *

     * @throws  AccessException if this registry is local and it denies

     * the caller access to perform this operation

     *

     * @throws  NullPointerException if <code>name</code> is <code>null</code>

     */

    public void unbind(String name)

        throws RemoteException, NotBoundException, AccessException;

    /**

     * Replaces the binding for the specified <code>name</code> in

     * this registry with the supplied remote reference.  If there is

     * an existing binding for the specified <code>name</code>, it is

     * discarded.

     *

     * @param   name the name to associate with the remote reference

     * @param   obj a reference to a remote object (usually a stub)

     *

     * @throws  RemoteException if remote communication with the

     * registry failed; if exception is a <code>ServerException</code>

     * containing an <code>AccessException</code>, then the registry

     * denies the caller access to perform this operation (if

     * originating from a non-local host, for example)

     *

     * @throws  AccessException if this registry is local and it denies

     * the caller access to perform this operation

     *

     * @throws  NullPointerException if <code>name</code> is

     * <code>null</code>, or if <code>obj</code> is <code>null</code>

     */

    public void rebind(String name, Remote obj)

        throws RemoteException, AccessException;

    /**

     * Returns an array of the names bound in this registry.  The

     * array will contain a snapshot of the names bound in this

     * registry at the time of the given invocation of this method.

     *

     * @return  an array of the names bound in this registry

     *

     * @throws  RemoteException if remote communication with the

     * registry failed; if exception is a <code>ServerException</code>

     * containing an <code>AccessException</code>, then the registry

     * denies the caller access to perform this operation

     *

     * @throws  AccessException if this registry is local and it denies

     * the caller access to perform this operation

     */

    public String[] list() throws RemoteException, AccessException;

}