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/*
* Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package java.net;
/**
* This class represents a Network Interface address. In short it's an
* IP address, a subnet mask and a broadcast address when the address is
* an IPv4 one. An IP address and a network prefix length in the case
* of IPv6 address.
*
* @see java.net.NetworkInterface
* @since 1.6
*/
public class InterfaceAddress {
private InetAddress address = null;
private Inet4Address broadcast = null;
private short maskLength = 0;
/*
* Package private constructor. Can't be built directly, instances are
* obtained through the NetworkInterface class.
*/
InterfaceAddress() {
}
// BEGIN Android-added: Rewrote NetworkInterface on top of Libcore.io.
InterfaceAddress(InetAddress address, Inet4Address broadcast, InetAddress netmask) {
this.address = address;
this.broadcast = broadcast;
this.maskLength = countPrefixLength(netmask);
}
/**
* Counts the prefix length for the netmask address.
*
* A valid netmask address must start with a continuous sequence of 1, followed by a continuous
* sequence of 0.
*/
private short countPrefixLength(InetAddress netmask) {
short count = 0;
for (byte b : netmask.getAddress()) {
for (; b != 0; b <<= 1, ++count);
}
return count;
}
// END Android-added: Rewrote NetworkInterface on top of Libcore.io.
/**
* Returns an {@code InetAddress} for this address.
*
* @return the {@code InetAddress} for this address.
*/
public InetAddress getAddress() {
return address;
}
/**
* Returns an {@code InetAddress} for the broadcast address
* for this InterfaceAddress.
*
* Only IPv4 networks have broadcast address therefore, in the case
* of an IPv6 network, {@code null} will be returned.
*
* @return the {@code InetAddress} representing the broadcast
* address or {@code null} if there is no broadcast address.
*/
public InetAddress getBroadcast() {
return broadcast;
}
/**
* Returns the network prefix length for this address. This is also known
* as the subnet mask in the context of IPv4 addresses.
* Typical IPv4 values would be 8 (255.0.0.0), 16 (255.255.0.0)
* or 24 (255.255.255.0).
* Typical IPv6 values would be 128 (::1/128) or 10 (fe80::203:baff:fe27:1243/10)
*
* @return a {@code short} representing the prefix length for the
* subnet of that address.
*/
public short getNetworkPrefixLength() {
return maskLength;
}
/**
* Compares this object against the specified object.
* The result is {@code true} if and only if the argument is
* not {@code null} and it represents the same interface address as
* this object.
*
* Two instances of {@code InterfaceAddress} represent the same
* address if the InetAddress, the prefix length and the broadcast are
* the same for both.
*
* @param obj the object to compare against.
* @return {@code true} if the objects are the same;
* {@code false} otherwise.
* @see java.net.InterfaceAddress#hashCode()
*/
public boolean equals(Object obj) {
if (!(obj instanceof InterfaceAddress)) {
return false;
}
InterfaceAddress cmp = (InterfaceAddress) obj;
if ( !(address == null ? cmp.address == null : address.equals(cmp.address)) )
return false;
if ( !(broadcast == null ? cmp.broadcast == null : broadcast.equals(cmp.broadcast)) )
return false;
if (maskLength != cmp.maskLength)
return false;
return true;
}
/**
* Returns a hashcode for this Interface address.
*
* @return a hash code value for this Interface address.
*/
public int hashCode() {
return address.hashCode() + ((broadcast != null) ? broadcast.hashCode() : 0) + maskLength;
}
/**
* Converts this Interface address to a {@code String}. The
* string returned is of the form: InetAddress / prefix length [ broadcast address ].
*
* @return a string representation of this Interface address.
*/
public String toString() {
return address + "/" + maskLength + " [" + broadcast + "]";
}
}