| /* |
| * Copyright (C) 2009 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package java.net; |
| |
| /** |
| * Identifies one of a network interface's addresses. |
| * These are passed back from the JNI behind NetworkInterface.getNetworkInterfaces. |
| * Multiple addresses for the same interface are collected together on the Java side. |
| * |
| * @hide |
| * @since 1.6 |
| */ |
| public class InterfaceAddress { |
| /** |
| * The kernel's interface index for the network interface this address |
| * is currently assigned to. Values start at 1, because 0 means "unknown" |
| * or "any", depending on context. |
| */ |
| final int index; |
| |
| /** |
| * The network interface's name. "lo" or "eth0", for example. |
| */ |
| final String name; |
| |
| /** |
| * An IPv4 or IPv6 address. |
| */ |
| final InetAddress address; |
| |
| /** |
| * The IPv4 broadcast address, or null for IPv6. |
| */ |
| private final InetAddress broadcastAddress; |
| |
| private final short prefixLength; |
| |
| InterfaceAddress(int index, String name, InetAddress address, InetAddress mask) { |
| assert ((address instanceof Inet4Address) == (mask instanceof Inet4Address)); |
| this.index = index; |
| this.name = name; |
| this.address = address; |
| this.broadcastAddress = makeBroadcastAddress(address, mask); |
| this.prefixLength = countPrefixLength(mask); |
| } |
| |
| private static InetAddress makeBroadcastAddress(InetAddress address, InetAddress mask) { |
| if (!(address instanceof Inet4Address)) { |
| return null; |
| } |
| byte[] broadcast = new byte[4]; |
| byte[] maskBytes = mask.ipaddress; |
| byte[] addrBytes = address.ipaddress; |
| if (maskBytes[0] != 0) { |
| for (int i = 0; i < broadcast.length; ++i) { |
| broadcast[i] = (byte) (addrBytes[i] | ~maskBytes[i]); |
| } |
| } |
| return new Inet4Address(broadcast); |
| } |
| |
| private static short countPrefixLength(InetAddress mask) { |
| short count = 0; |
| for (byte b : mask.ipaddress) { |
| for (int i = 0; i < 8; ++i) { |
| if ((b & (1 << i)) != 0) { |
| ++count; |
| } |
| } |
| } |
| return count; |
| } |
| |
| /** |
| * Tests whether this object is equal to another one. Returns true if |
| * the address, broadcast address and prefix length are all equal. |
| * |
| * @param obj the object to be compared. |
| * @return true if 'obj' is equal to this InterfaceAddress, false otherwise. |
| */ |
| @Override |
| public boolean equals(Object obj) { |
| if (obj == this){ |
| return true; |
| } |
| if (!(obj instanceof InterfaceAddress)) { |
| return false; |
| } |
| InterfaceAddress rhs = (InterfaceAddress) obj; |
| return ((address == null) ? rhs.address == null : address.equals(rhs.address)) && |
| (rhs.prefixLength == prefixLength) && |
| ((broadcastAddress == null) ? rhs.broadcastAddress == null : broadcastAddress.equals(rhs.broadcastAddress)); |
| } |
| |
| @Override |
| public int hashCode() { |
| int hashCode = address == null ? 0 : -address.hashCode(); |
| hashCode += broadcastAddress == null ? 0 : broadcastAddress.hashCode(); |
| hashCode += prefixLength; |
| return hashCode; |
| } |
| |
| /** |
| * Returns a string representation for this interface address. |
| * The string is of the form: InetAddress / prefix length [ broadcast address ]. |
| * |
| * @return a string representation of this interface address. |
| */ |
| @Override |
| public String toString() { |
| return address + "/" + prefixLength + " [" + broadcastAddress + "]"; |
| } |
| |
| /** |
| * Returns the InetAddress for this address. |
| */ |
| public InetAddress getAddress() { |
| return address; |
| } |
| |
| /** |
| * Returns the subnet-directed broadcast address if this is an IPv4 interface, null otherwise. |
| */ |
| public InetAddress getBroadcast() { |
| return broadcastAddress; |
| } |
| |
| /** |
| * Returns the network prefix length in bits. |
| * (In IPv4 parlance, this is known as the subnet mask, |
| * but this method applies to IPv6 addresses too.) |
| */ |
| public short getNetworkPrefixLength() { |
| return prefixLength; |
| } |
| } |