/* * Copyright (c) 2002, 2005, 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;import java.io.IOException; /* * Package private implementation of InetAddressImpl for dual * IPv4/IPv6 stack. * <p> * If InetAddress.preferIPv6Address is true then anyLocalAddress(), * loopbackAddress(), and localHost() will return IPv6 addresses, * otherwise IPv4 addresses. * * @since 1.4 */ class Inet6AddressImpl implements InetAddressImpl {    public native String getLocalHostName() throws UnknownHostException;    public native InetAddress[]        lookupAllHostAddr(String hostname) throws UnknownHostException;    public native String getHostByAddr(byte[] addr) throws UnknownHostException;    private native boolean isReachable0(byte[] addr, int scope, int timeout, byte[] inf, int ttl, int if_scope) throws IOException;     public boolean isReachable(InetAddress addr, int timeout, NetworkInterface netif, int ttl) throws IOException {        byte[] ifaddr = null;        int scope = -1;        int netif_scope = -1;        if (netif != null) {            /*             * Let's make sure we bind to an address of the proper family.             * Which means same family as addr because at this point it could             * be either an IPv6 address or an IPv4 address (case of a dual             * stack system).             */            java.util.Enumeration it = netif.getInetAddresses();            InetAddress inetaddr = null;            while (it.hasMoreElements()) {                inetaddr = (InetAddress) it.nextElement();                if (inetaddr.getClass().isInstance(addr)) {                    ifaddr = inetaddr.getAddress();                    if (inetaddr instanceof Inet6Address) {                        netif_scope = ((Inet6Address) inetaddr).getScopeId();                    }                    break;                }            }            if (ifaddr == null) {                // Interface doesn't support the address family of                // the destination                return false;            }        }        if (addr instanceof Inet6Address)            scope = ((Inet6Address) addr).getScopeId();        return isReachable0(addr.getAddress(), scope, timeout, ifaddr, ttl, netif_scope);    }     public synchronized InetAddress anyLocalAddress() {        if (anyLocalAddress == null) {            if (InetAddress.preferIPv6Address) {                anyLocalAddress = new Inet6Address();                anyLocalAddress.hostName = "::";            } else {                anyLocalAddress = (new Inet4AddressImpl()).anyLocalAddress();            }        }        return anyLocalAddress;    }     public synchronized InetAddress loopbackAddress() {        if (loopbackAddress == null) {             if (InetAddress.preferIPv6Address) {                 byte[] loopback =                        {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,                         0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};                 loopbackAddress = new Inet6Address("localhost", loopback);             } else {                loopbackAddress = (new Inet4AddressImpl()).loopbackAddress();             }        }        return loopbackAddress;    }     private InetAddress      anyLocalAddress;    private InetAddress      loopbackAddress;}