1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://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,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.net;
18
19import android.os.Parcel;
20import android.os.Parcelable;
21
22import java.net.Inet4Address;
23import java.net.InetAddress;
24import java.net.InterfaceAddress;
25import java.net.UnknownHostException;
26
27/**
28 * Identifies an address of a network link
29 * @hide
30 */
31public class LinkAddress implements Parcelable {
32    /**
33     * IPv4 or IPv6 address.
34     */
35    private final InetAddress address;
36
37    /**
38     * Network prefix length
39     */
40    private final int prefixLength;
41
42    public LinkAddress(InetAddress address, int prefixLength) {
43        if (address == null || prefixLength < 0 ||
44                ((address instanceof Inet4Address) && prefixLength > 32) ||
45                (prefixLength > 128)) {
46            throw new IllegalArgumentException("Bad LinkAddress params " + address +
47                    prefixLength);
48        }
49        this.address = address;
50        this.prefixLength = prefixLength;
51    }
52
53    public LinkAddress(InterfaceAddress interfaceAddress) {
54        this.address = interfaceAddress.getAddress();
55        this.prefixLength = interfaceAddress.getNetworkPrefixLength();
56    }
57
58    @Override
59    public String toString() {
60        return (address == null ? "" : (address.getHostAddress() + "/" + prefixLength));
61    }
62
63    /**
64     * Compares this {@code LinkAddress} instance against the specified address
65     * in {@code obj}. Two addresses are equal if their InetAddress and prefixLength
66     * are equal
67     *
68     * @param obj the object to be tested for equality.
69     * @return {@code true} if both objects are equal, {@code false} otherwise.
70     */
71    @Override
72    public boolean equals(Object obj) {
73        if (!(obj instanceof LinkAddress)) {
74            return false;
75        }
76        LinkAddress linkAddress = (LinkAddress) obj;
77        return this.address.equals(linkAddress.address) &&
78            this.prefixLength == linkAddress.prefixLength;
79    }
80
81    @Override
82    /*
83     * generate hashcode based on significant fields
84     */
85    public int hashCode() {
86        return ((null == address) ? 0 : address.hashCode()) + prefixLength;
87    }
88
89    /**
90     * Returns the InetAddress for this address.
91     */
92    public InetAddress getAddress() {
93        return address;
94    }
95
96    /**
97     * Get network prefix length
98     */
99    public int getNetworkPrefixLength() {
100        return prefixLength;
101    }
102
103    /**
104     * Implement the Parcelable interface
105     * @hide
106     */
107    public int describeContents() {
108        return 0;
109    }
110
111    /**
112     * Implement the Parcelable interface.
113     * @hide
114     */
115    public void writeToParcel(Parcel dest, int flags) {
116        if (address != null) {
117            dest.writeByte((byte)1);
118            dest.writeByteArray(address.getAddress());
119            dest.writeInt(prefixLength);
120        } else {
121            dest.writeByte((byte)0);
122        }
123    }
124
125    /**
126     * Implement the Parcelable interface.
127     * @hide
128     */
129    public static final Creator<LinkAddress> CREATOR =
130        new Creator<LinkAddress>() {
131            public LinkAddress createFromParcel(Parcel in) {
132                InetAddress address = null;
133                int prefixLength = 0;
134                if (in.readByte() == 1) {
135                    try {
136                        address = InetAddress.getByAddress(in.createByteArray());
137                        prefixLength = in.readInt();
138                    } catch (UnknownHostException e) { }
139                }
140                return new LinkAddress(address, prefixLength);
141            }
142
143            public LinkAddress[] newArray(int size) {
144                return new LinkAddress[size];
145            }
146        };
147}
148