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