1/*
2 * Copyright (c) 1996, 2001, 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
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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
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19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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24 */
25package java.rmi.registry;
26
27import java.rmi.AccessException;
28import java.rmi.AlreadyBoundException;
29import java.rmi.NotBoundException;
30import java.rmi.Remote;
31import java.rmi.RemoteException;
32
33/**
34 * <code>Registry</code> is a remote interface to a simple remote
35 * object registry that provides methods for storing and retrieving
36 * remote object references bound with arbitrary string names.  The
37 * <code>bind</code>, <code>unbind</code>, and <code>rebind</code>
38 * methods are used to alter the name bindings in the registry, and
39 * the <code>lookup</code> and <code>list</code> methods are used to
40 * query the current name bindings.
41 *
42 * <p>In its typical usage, a <code>Registry</code> enables RMI client
43 * bootstrapping: it provides a simple means for a client to obtain an
44 * initial reference to a remote object.  Therefore, a registry's
45 * remote object implementation is typically exported with a
46 * well-known address, such as with a well-known {@link
47 * java.rmi.server.ObjID#REGISTRY_ID ObjID} and TCP port number
48 * (default is {@link #REGISTRY_PORT 1099}).
49 *
50 * <p>The {@link LocateRegistry} class provides a programmatic API for
51 * constructing a bootstrap reference to a <code>Registry</code> at a
52 * remote address (see the static <code>getRegistry</code> methods)
53 * and for creating and exporting a <code>Registry</code> in the
54 * current VM on a particular local address (see the static
55 * <code>createRegistry</code> methods).
56 *
57 * <p>A <code>Registry</code> implementation may choose to restrict
58 * access to some or all of its methods (for example, methods that
59 * mutate the registry's bindings may be restricted to calls
60 * originating from the local host).  If a <code>Registry</code>
61 * method chooses to deny access for a given invocation, its
62 * implementation may throw {@link java.rmi.AccessException}, which
63 * (because it extends {@link java.rmi.RemoteException}) will be
64 * wrapped in a {@link java.rmi.ServerException} when caught by a
65 * remote client.
66 *
67 * <p>The names used for bindings in a <code>Registry</code> are pure
68 * strings, not parsed.  A service which stores its remote reference
69 * in a <code>Registry</code> may wish to use a package name as a
70 * prefix in the name binding to reduce the likelihood of name
71 * collisions in the registry.
72 *
73 * @author      Ann Wollrath
74 * @author      Peter Jones
75 * @since       1.1
76 * @see         LocateRegistry
77 */
78public interface Registry extends Remote {
79
80    /** Well known port for registry. */
81    public static final int REGISTRY_PORT = 1099;
82
83    /**
84     * Returns the remote reference bound to the specified
85     * <code>name</code> in this registry.
86     *
87     * @param   name the name for the remote reference to look up
88     *
89     * @return  a reference to a remote object
90     *
91     * @throws  NotBoundException if <code>name</code> is not currently bound
92     *
93     * @throws  RemoteException if remote communication with the
94     * registry failed; if exception is a <code>ServerException</code>
95     * containing an <code>AccessException</code>, then the registry
96     * denies the caller access to perform this operation
97     *
98     * @throws  AccessException if this registry is local and it denies
99     * the caller access to perform this operation
100     *
101     * @throws  NullPointerException if <code>name</code> is <code>null</code>
102     */
103    public Remote lookup(String name)
104        throws RemoteException, NotBoundException, AccessException;
105
106    /**
107     * Binds a remote reference to the specified <code>name</code> in
108     * this registry.
109     *
110     * @param   name the name to associate with the remote reference
111     * @param   obj a reference to a remote object (usually a stub)
112     *
113     * @throws  AlreadyBoundException if <code>name</code> is already bound
114     *
115     * @throws  RemoteException if remote communication with the
116     * registry failed; if exception is a <code>ServerException</code>
117     * containing an <code>AccessException</code>, then the registry
118     * denies the caller access to perform this operation (if
119     * originating from a non-local host, for example)
120     *
121     * @throws  AccessException if this registry is local and it denies
122     * the caller access to perform this operation
123     *
124     * @throws  NullPointerException if <code>name</code> is
125     * <code>null</code>, or if <code>obj</code> is <code>null</code>
126     */
127    public void bind(String name, Remote obj)
128        throws RemoteException, AlreadyBoundException, AccessException;
129
130    /**
131     * Removes the binding for the specified <code>name</code> in
132     * this registry.
133     *
134     * @param   name the name of the binding to remove
135     *
136     * @throws  NotBoundException if <code>name</code> is not currently bound
137     *
138     * @throws  RemoteException if remote communication with the
139     * registry failed; if exception is a <code>ServerException</code>
140     * containing an <code>AccessException</code>, then the registry
141     * denies the caller access to perform this operation (if
142     * originating from a non-local host, for example)
143     *
144     * @throws  AccessException if this registry is local and it denies
145     * the caller access to perform this operation
146     *
147     * @throws  NullPointerException if <code>name</code> is <code>null</code>
148     */
149    public void unbind(String name)
150        throws RemoteException, NotBoundException, AccessException;
151
152    /**
153     * Replaces the binding for the specified <code>name</code> in
154     * this registry with the supplied remote reference.  If there is
155     * an existing binding for the specified <code>name</code>, it is
156     * discarded.
157     *
158     * @param   name the name to associate with the remote reference
159     * @param   obj a reference to a remote object (usually a stub)
160     *
161     * @throws  RemoteException if remote communication with the
162     * registry failed; if exception is a <code>ServerException</code>
163     * containing an <code>AccessException</code>, then the registry
164     * denies the caller access to perform this operation (if
165     * originating from a non-local host, for example)
166     *
167     * @throws  AccessException if this registry is local and it denies
168     * the caller access to perform this operation
169     *
170     * @throws  NullPointerException if <code>name</code> is
171     * <code>null</code>, or if <code>obj</code> is <code>null</code>
172     */
173    public void rebind(String name, Remote obj)
174        throws RemoteException, AccessException;
175
176    /**
177     * Returns an array of the names bound in this registry.  The
178     * array will contain a snapshot of the names bound in this
179     * registry at the time of the given invocation of this method.
180     *
181     * @return  an array of the names bound in this registry
182     *
183     * @throws  RemoteException if remote communication with the
184     * registry failed; if exception is a <code>ServerException</code>
185     * containing an <code>AccessException</code>, then the registry
186     * denies the caller access to perform this operation
187     *
188     * @throws  AccessException if this registry is local and it denies
189     * the caller access to perform this operation
190     */
191    public String[] list() throws RemoteException, AccessException;
192}
193