1 /* 2 * Copyright (C) 2009 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 17 package java.net; 18 19 /** 20 * Identifies one of a network interface's addresses. 21 * These are passed back from the JNI behind NetworkInterface.getNetworkInterfaces. 22 * Multiple addresses for the same interface are collected together on the Java side. 23 * 24 * @since 1.6 25 */ 26 public class InterfaceAddress { 27 /** 28 * An IPv4 or IPv6 address. 29 */ 30 private final InetAddress address; 31 32 /** 33 * The IPv4 broadcast address, or null for IPv6. 34 */ 35 private final InetAddress broadcastAddress; 36 37 private final short prefixLength; 38 39 /** 40 * For IPv4. 41 */ InterfaceAddress(Inet4Address address, Inet4Address broadcastAddress, Inet4Address mask)42 InterfaceAddress(Inet4Address address, Inet4Address broadcastAddress, Inet4Address mask) { 43 this.address = address; 44 this.broadcastAddress = broadcastAddress; 45 this.prefixLength = countPrefixLength(mask); 46 } 47 48 /** 49 * For IPv6. 50 */ InterfaceAddress(Inet6Address address, short prefixLength)51 InterfaceAddress(Inet6Address address, short prefixLength) { 52 this.address = address; 53 this.broadcastAddress = null; 54 this.prefixLength = prefixLength; 55 } 56 countPrefixLength(Inet4Address mask)57 private static short countPrefixLength(Inet4Address mask) { 58 short count = 0; 59 for (byte b : mask.ipaddress) { 60 for (int i = 0; i < 8; ++i) { 61 if ((b & (1 << i)) != 0) { 62 ++count; 63 } 64 } 65 } 66 return count; 67 } 68 69 /** 70 * Tests whether this object is equal to another one. Returns true if 71 * the address, broadcast address and prefix length are all equal. 72 * 73 * @param obj the object to be compared. 74 * @return true if 'obj' is equal to this InterfaceAddress, false otherwise. 75 */ 76 @Override equals(Object obj)77 public boolean equals(Object obj) { 78 if (obj == this){ 79 return true; 80 } 81 if (!(obj instanceof InterfaceAddress)) { 82 return false; 83 } 84 InterfaceAddress rhs = (InterfaceAddress) obj; 85 return ((address == null) ? rhs.address == null : address.equals(rhs.address)) && 86 (rhs.prefixLength == prefixLength) && 87 ((broadcastAddress == null) ? rhs.broadcastAddress == null : broadcastAddress.equals(rhs.broadcastAddress)); 88 } 89 90 @Override hashCode()91 public int hashCode() { 92 int hashCode = address == null ? 0 : -address.hashCode(); 93 hashCode += broadcastAddress == null ? 0 : broadcastAddress.hashCode(); 94 hashCode += prefixLength; 95 return hashCode; 96 } 97 98 /** 99 * Returns a string containing this interface's address, prefix length, and broadcast address. 100 * For example: {@code "/172.18.103.112/23 [/172.18.103.255]"} or 101 * {@code "/0:0:0:0:0:0:0:1%1/128 [null]"}. 102 */ toString()103 @Override public String toString() { 104 return address + "/" + prefixLength + " [" + broadcastAddress + "]"; 105 } 106 107 /** 108 * Returns the InetAddress for this address. 109 */ getAddress()110 public InetAddress getAddress() { 111 return address; 112 } 113 114 /** 115 * Returns the subnet-directed broadcast address if this is an IPv4 interface, null otherwise. 116 */ getBroadcast()117 public InetAddress getBroadcast() { 118 return broadcastAddress; 119 } 120 121 /** 122 * Returns the network prefix length in bits. 123 * (In IPv4 parlance, this is known as the subnet mask, 124 * but this method applies to IPv6 addresses too.) 125 */ getNetworkPrefixLength()126 public short getNetworkPrefixLength() { 127 return prefixLength; 128 } 129 } 130