1 /*
2 * Copyright (c) 2019, 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 java.net;
27
28 import java.io.ObjectStreamException;
29 import java.io.Serializable;
30 import java.net.SocketAddress;
31 import java.nio.channels.SocketChannel;
32 import java.nio.file.FileSystem;
33 import java.nio.file.FileSystems;
34 import java.nio.file.InvalidPathException;
35 import java.nio.file.Path;
36
37 /**
38 * A <a href="package-summary.html#unixdomain">Unix domain</a> socket address.
39 * A Unix domain socket address encapsulates a file-system path that Unix domain sockets
40 * bind or connect to.
41 *
42 * <p> An <a id="unnamed"></a><i>unnamed</i> {@code UnixDomainSocketAddress} has
43 * an empty path. The local address of a {@link SocketChannel} to a Unix domain socket
44 * that is <i>automatically</i> or <i>implicitly</i> bound will be unnamed.
45 *
46 * <p> {@link Path} objects used to create instances of this class must be obtained
47 * from the {@linkplain FileSystems#getDefault system-default} file system.
48 *
49 * @see java.nio.channels.SocketChannel
50 * @see java.nio.channels.ServerSocketChannel
51 * @since 16
52 */
53 public final class UnixDomainSocketAddress extends SocketAddress {
54 @java.io.Serial
55 static final long serialVersionUID = 92902496589351288L;
56
57 private final transient Path path;
58
59 /**
60 * A serial proxy for all {@link UnixDomainSocketAddress} instances.
61 * It captures the file path name and reconstructs using the public static
62 * {@link #of(String) factory}.
63 *
64 * @serial include
65 */
66 private static final class Ser implements Serializable {
67 @java.io.Serial
68 static final long serialVersionUID = -7955684448513979814L;
69
70 /**
71 * The path name.
72 * @serial
73 */
74 private final String pathname;
75
76 Ser(String pathname) {
77 this.pathname = pathname;
78 }
79
80 /**
81 * Creates a {@link UnixDomainSocketAddress} instance, by an invocation
82 * of the {@link #of(String) factory} method passing the path name.
83 * @return a UnixDomainSocketAddress
84 */
85 @java.io.Serial
86 private Object readResolve() {
87 return UnixDomainSocketAddress.of(pathname);
88 }
89 }
90
91 /**
92 * Returns a
93 * <a href="{@docRoot}/serialized-form.html#java.net.UnixDomainSocketAddress.Ser">
94 * Ser</a> containing the path name of this instance.
95 *
96 * @return a {@link Ser}
97 * representing the path name of this instance
98 */
99 @java.io.Serial
100 private Object writeReplace() throws ObjectStreamException {
101 return new Ser(path.toString());
102 }
103
104 /**
105 * Throws InvalidObjectException, always.
106 * @param s the stream
107 * @throws java.io.InvalidObjectException always
108 */
109 @java.io.Serial
110 private void readObject(java.io.ObjectInputStream s)
111 throws java.io.InvalidObjectException
112 {
113 throw new java.io.InvalidObjectException("Proxy required");
114 }
115
116 /**
117 * Throws InvalidObjectException, always.
118 * @throws java.io.InvalidObjectException always
119 */
120 @java.io.Serial
121 private void readObjectNoData()
122 throws java.io.InvalidObjectException
123 {
124 throw new java.io.InvalidObjectException("Proxy required");
125 }
126
127 private UnixDomainSocketAddress(Path path) {
128 FileSystem fs = path.getFileSystem();
129 if (fs != FileSystems.getDefault()) {
130 throw new IllegalArgumentException();
131 }
132 if (fs.getClass().getModule() != Object.class.getModule()) {
133 throw new IllegalArgumentException();
134 }
135 this.path = path;
136 }
137
138 /**
139 * Create a UnixDomainSocketAddress from the given path string.
140 *
141 * @param pathname
142 * The path string, which can be empty
143 *
144 * @return A UnixDomainSocketAddress
145 *
146 * @throws InvalidPathException
147 * If the path cannot be converted to a Path
148 *
149 * @throws NullPointerException if pathname is {@code null}
150 */
151 public static UnixDomainSocketAddress of(String pathname) {
152 return of(Path.of(pathname));
153 }
154
155 /**
156 * Create a UnixDomainSocketAddress for the given path.
157 *
158 * @param path
159 * The path to the socket, which can be empty
160 *
161 * @return A UnixDomainSocketAddress
162 *
163 * @throws IllegalArgumentException
164 * If the path is not associated with the default file system
165 *
166 * @throws NullPointerException if path is {@code null}
167 */
168 public static UnixDomainSocketAddress of(Path path) {
169 return new UnixDomainSocketAddress(path);
170 }
171
172 /**
173 * Return this address's path.
174 *
175 * @return this address's path
176 */
177 public Path getPath() {
178 return path;
179 }
180
181 /**
182 * Returns the hash code of this {@code UnixDomainSocketAddress}
183 */
184 @Override
185 public int hashCode() {
186 return path.hashCode();
187 }
188
189 /**
190 * Compares this address with another object.
191 *
192 * @return true if the path fields are equal
193 */
194 @Override
195 public boolean equals(Object o) {
196 if (!(o instanceof UnixDomainSocketAddress))
197 return false;
198 UnixDomainSocketAddress that = (UnixDomainSocketAddress)o;
199 return this.path.equals(that.path);
200 }
201
202 /**
203 * Returns a string representation of this {@code UnixDomainSocketAddress}.
204 *
205 * @return this address's path which may be empty for an unnamed address
206 */
207 @Override
208 public String toString() {
209 return path.toString();
210 }
211 }