1 /*
2 * Copyright 2012 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * https://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package io.netty.channel.socket;
17
18 import io.netty.util.NetUtil;
19
20 import java.net.Inet4Address;
21 import java.net.Inet6Address;
22 import java.net.InetAddress;
23
24 /**
25 * Internet Protocol (IP) families used by the {@link DatagramChannel}
26 */
27 public enum InternetProtocolFamily {
28 IPv4(Inet4Address.class, 1),
29 IPv6(Inet6Address.class, 2);
30
31 private final Class<? extends InetAddress> addressType;
32 private final int addressNumber;
33
34 InternetProtocolFamily(Class<? extends InetAddress> addressType, int addressNumber) {
35 this.addressType = addressType;
36 this.addressNumber = addressNumber;
37 }
38
39 /**
40 * Returns the address type of this protocol family.
41 */
42 public Class<? extends InetAddress> addressType() {
43 return addressType;
44 }
45
46 /**
47 * Returns the
48 * <a href="https://www.iana.org/assignments/address-family-numbers/address-family-numbers.xhtml">address number</a>
49 * of the family.
50 */
51 public int addressNumber() {
52 return addressNumber;
53 }
54
55 /**
56 * Returns the {@link InetAddress} that represent the {@code LOCALHOST} for the family.
57 */
58 public InetAddress localhost() {
59 switch (this) {
60 case IPv4:
61 return NetUtil.LOCALHOST4;
62 case IPv6:
63 return NetUtil.LOCALHOST6;
64 default:
65 throw new IllegalStateException("Unsupported family " + this);
66 }
67 }
68
69 /**
70 * Returns the {@link InternetProtocolFamily} for the given {@link InetAddress}.
71 */
72 public static InternetProtocolFamily of(InetAddress address) {
73 if (address instanceof Inet4Address) {
74 return IPv4;
75 }
76 if (address instanceof Inet6Address) {
77 return IPv6;
78 }
79 throw new IllegalArgumentException("address " + address + " not supported");
80 }
81 }