Java InetAddress Check isPublicIp(InetAddress addr)

Description

See if given address is public or not

License

Open Source License

Parameter

Parameter	Description
addr	target address

Return

true : public address

Declaration

public static boolean isPublicIp(InetAddress addr) 

Method Source Code

//package com.java2s;
/*// ww  w  . j a v  a2  s  .  c o m
 License:
    
 blueprint-sdk is licensed under the terms of Eclipse Public License(EPL) v1.0
 (http://www.eclipse.org/legal/epl-v10.html)
    
    
 Distribution:
    
 Repository - https://github.com/lempel/blueprint-sdk.git
 Blog - http://lempel.egloos.com
 */

import java.net.*;

public class Main {
    /**
     * See if given address is public or not
     *
     * @param addr target address
     * @return true : public address
     */
    public static boolean isPublicIp(InetAddress addr) {
        return !(isPrivateIp(addr) || isLoopbackIp(addr));
    }

    /**
     * See if given address is private or not
     *
     * @param addr target address
     * @return true : private network
     */
    public static boolean isPrivateIp(InetAddress addr) {
        boolean result = false;

        if (addr instanceof Inet4Address) {
            result = isPrivateIp((Inet4Address) addr);
        } else if (addr instanceof Inet6Address) {
            result = isPrivateIp((Inet6Address) addr);
        }

        return result;
    }

    /**
     * See if given address is private or not
     *
     * @param addr IPv4 address
     * @return true : private network
     */
    public static boolean isPrivateIp(Inet4Address addr) {
        boolean result = false;

        byte[] address = addr.getAddress();

        if (address[0] == 10) {
            // 10.*.*.*
            result = true;
        } else if ((address[0] & 0x000000ff) == 0xa9 && (address[1] & 0x000000ff) == 0xfe) {
            // 169.254.*.*
            result = true;
        } else if ((address[0] & 0x000000ff) == 0xac
                && ((address[1] & 0x000000ff) >= 16 && (address[1] & 0x000000ff) <= 31)) {
            // 172.16.*.* ~ 172.31.*.*
            result = true;
        } else if ((address[0] & 0x000000ff) == 0xc0 && (address[1] & 0x000000ff) == 0xa8) {
            // 192.168.*.*
            result = true;
        }

        return result;
    }

    /**
     * See if given address is private or not
     *
     * @param addr IPv6 address
     * @return true : private network
     */
    public static boolean isPrivateIp(Inet6Address addr) {
        boolean result = false;

        byte[] address = addr.getAddress();

        if ((address[0] & 0x000000ff) == 0xfc && (address[1] & 0x000000ff) == 0x00) {
            result = true;
        } else if ((address[0] & 0x000000ff) == 0xfe && (address[1] & 0x000000ff) == 0x80) {
            result = true;
        }

        return result;
    }

    /**
     * See if given address is loopback or not
     *
     * @param addr target address
     * @return true : private network
     */
    public static boolean isLoopbackIp(InetAddress addr) {
        boolean result = false;

        if (addr instanceof Inet4Address) {
            result = isLoopbackIp((Inet4Address) addr);
        } else if (addr instanceof Inet6Address) {
            result = isLoopbackIp((Inet6Address) addr);
        }

        return result;
    }

    /**
     * See if given address is loopback or not
     *
     * @param addr IPv4 address
     * @return true : private network
     */
    public static boolean isLoopbackIp(Inet4Address addr) {
        boolean result = false;

        byte[] address = addr.getAddress();

        if ((address[0] & 0x000000ff) == 0x7f) {
            // 127.*.*.*
            result = true;
        }

        return result;
    }

    /**
     * See if given address is loopback or not
     *
     * @param addr IPv6 address
     * @return true : private network
     */
    public static boolean isLoopbackIp(Inet6Address addr) {
        boolean result = false;

        byte[] address = addr.getAddress();

        boolean allZero = true;
        for (byte abyte : address) {
            if (abyte != 0) {
                allZero = false;
                break;
            }
        }

        if (allZero && address[address.length - 1] == 1) {
            result = true;
        }

        return result;
    }
}

Related

1. isPrivateIp(InetAddress addr)
2. isPrivateIP(InetAddress ip)
3. isPrivateNetworkAddress(final InetAddress inetAddress)
4. isPrivateSubnet(InetAddress address)
5. isPublic(InetAddress inetAddress)
6. isPublicIP4Address(InetAddress localAddress)
7. isPubliclyRoutable(final InetAddress addrIP)
8. isReachable(final InetAddress inetAddress, final int timeout)
9. isReachable(InetAddress address, int port)