实用程序例程，检查InetAddress是否是IPv4映射的IPv6地址。

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//package com.nowjava;


public class Main {/** n  o  w  j  a  v  a . c o m 提 供 **/

    public static void main(String[] argv) throws Exception {

        byte[] addr = new byte[] { 34, 35, 36, 37, 37, 37, 67, 68, 69 };

        System.out.println(isIPv4MappedAddress(addr));

    }


    private static final int INADDR16SZ = 16;


    /**

     * Utility routine to check if the InetAddress is an

     * IPv4 mapped IPv6 address.

     *

     * @return a <code>boolean</code> indicating if the InetAddress is

     * an IPv4 mapped IPv6 address; or false if address is IPv4 address.

     */

    private static boolean isIPv4MappedAddress(byte[] addr) {

        if (addr.length < INADDR16SZ) {

            return false;

        }

        if ((addr[0] == 0x00) && (addr[1] == 0x00) && (addr[2] == 0x00)

                && (addr[3] == 0x00) && (addr[4] == 0x00)

                && (addr[5] == 0x00) && (