Java获取ip地址的几种方法

以下内容介绍下java获取ip地址的几种思路。

１、直接利用java.net.InetAddress类获取，不过这种方法只在windows环境下有效，在linux环境下只能获取localhost地址（即/etc/hosts文件内容）

　　代码如下：　

     import java.net.InetAddress;
/**

      * This method works well in windows system.

      * In Linux system it returns 127.0.0.1 the content of the hosts file.

      */

     public static void getIpAddressInWindows() {

         try {

             InetAddress address = InetAddress.getLocalHost();

             System.out.println("Host Name: " + address.getHostName());

             System.out.println("Host Address: " + address.getHostAddress());
} catch (UnknownHostException e) {

             e.printStackTrace();

         }

     } 

２、可以在linux下正常工作的方法，代码如下：

    /**

     * This method is used to get all ip addresses from the network interfaces.

     * network interfaces: eth0, wlan0, l0, vmnet1, vmnet8

     */

    public static void getAllIpAddress() {

        try {

            //get all network interface

            Enumeration<NetworkInterface> allNetworkInterfaces =

                    NetworkInterface.getNetworkInterfaces();

            NetworkInterface networkInterface = null;
//check if there are more than one network interface

            while (allNetworkInterfaces.hasMoreElements()) {

                //get next network interface

                networkInterface = allNetworkInterfaces.nextElement();

                //output interface's name

                System.out.println("network interface: " +

                        networkInterface.getDisplayName());
//get all ip address that bound to this network interface

                Enumeration<InetAddress> allInetAddress =

                        networkInterface.getInetAddresses();
InetAddress ipAddress = null;
//check if there are more than one ip addresses

                //band to one network interface

                while (allInetAddress.hasMoreElements()) {

                    //get next ip address

                    ipAddress = allInetAddress.nextElement();

                    if (ipAddress != null && ipAddress instanceof Inet4Address) {

                        System.out.println("ip address: " +

                                ipAddress.getHostAddress());

                    }

                }

            }
} catch (SocketException e) {

            e.printStackTrace();

        }

    }//end method getAllIpAddress
                            

上边这种方法有些不足之处，它会输出所有的网卡上的ip地址，有时候我们只需一个或几个单独的网卡ip即可，可以通过如下方法获得：　　　　

       /**

      * This method is used to get ip address by network interface's name.

      * @param networkInterfaceName network interface's name

      * @return return true if get ip address successfully,

      * otherwise return false.

      */

     public static boolean getIpAddrByName(String networkInterfaceName) {

         try {

 　　　　　　　 //get network interface by name

             NetworkInterface networkInterface =

                     NetworkInterface.getByName(networkInterfaceName);

             if (networkInterface == null) {

                 return false;

             }

             System.out.println("network interface: " +

                     networkInterface.getDisplayName());
InetAddress ipAddress = null;

             //get all ip addresses band to this interface

             Enumeration<InetAddress> addresses = networkInterface.getInetAddresses();
while (addresses.hasMoreElements()) {

                 ipAddress = addresses.nextElement();
if (ipAddress != null && ipAddress instanceof Inet4Address) {

                     System.out.println("ip address: " +

                             ipAddress.getHostAddress());

                 }

             }

         } catch (SocketException e) {

             e.printStackTrace();

         }
return true;

     }// end method getIpAddrByName