我正在尝试开发一个系统,其中有不同的节点运行在不同的系统或在同一系统的不同端口上。

现在,所有节点都创建了一个套接字,将目标IP作为称为引导节点的特殊节点的IP。然后,节点创建自己的ServerSocket并开始侦听连接。

引导节点维护一个节点列表,并在查询时返回它们。

现在我需要的是节点必须将其IP注册到引导节点。我尝试使用cli.getInetAddress()一旦客户端连接到引导节点的ServerSocket,但这不起作用。

我需要客户端注册其PPP IP,如果可用; 否则,局域网IP(如果可用); 否则,它必须注册127.0.0.1,假设它是同一台计算机。

使用代码:

System.out.println(Inet4Address.getLocalHost().getHostAddress());

or

System.out.println(InetAddress.getLocalHost().getHostAddress());

我的PPP连接IP地址是:117.204.44.192,但上面返回我192.168.1.2

EDIT

我正在使用以下代码:

Enumeration e = NetworkInterface.getNetworkInterfaces();
while(e.hasMoreElements())
{
    NetworkInterface n = (NetworkInterface) e.nextElement();
    Enumeration ee = n.getInetAddresses();
    while (ee.hasMoreElements())
    {
        InetAddress i = (InetAddress) ee.nextElement();
        System.out.println(i.getHostAddress());
    }
}

我能够获得所有网络接口相关的所有IP地址,但我如何区分它们?这是我得到的输出:

127.0.0.1
192.168.1.2
192.168.56.1
117.204.44.19

当前回答

使用InetAddress.getLocalHost()获取本地地址

import java.net.InetAddress;

try {
  InetAddress addr = InetAddress.getLocalHost();            
  System.out.println(addr.getHostAddress());
} catch (UnknownHostException e) {
}

其他回答

scala中的示例(在sbt文件中有用):

  import collection.JavaConverters._
  import java.net._

  def getIpAddress: String = {

    val enumeration = NetworkInterface.getNetworkInterfaces.asScala.toSeq

    val ipAddresses = enumeration.flatMap(p =>
      p.getInetAddresses.asScala.toSeq
    )

    val address = ipAddresses.find { address =>
      val host = address.getHostAddress
      host.contains(".") && !address.isLoopbackAddress
    }.getOrElse(InetAddress.getLocalHost)

    address.getHostAddress
  }

通常当我试图找到我的公共IP地址,如cmyip.com或www.iplocation.net,我使用这种方式:

public static String myPublicIp() {

    /*nslookup myip.opendns.com resolver1.opendns.com*/
    String ipAdressDns  = "";
    try {
        String command = "nslookup myip.opendns.com resolver1.opendns.com";
        Process proc = Runtime.getRuntime().exec(command);

        BufferedReader stdInput = new BufferedReader(new InputStreamReader(proc.getInputStream()));

        String s;
        while ((s = stdInput.readLine()) != null) {
            ipAdressDns  += s + "\n";
        }
    } catch (IOException e) {
        e.printStackTrace();
    }

    return ipAdressDns ;
}

一个相当简单的方法似乎很有效……

String getPublicIPv4() throws UnknownHostException, SocketException{
    Enumeration<NetworkInterface> e = NetworkInterface.getNetworkInterfaces();
    String ipToReturn = null;
    while(e.hasMoreElements())
    {
        NetworkInterface n = (NetworkInterface) e.nextElement();
        Enumeration<InetAddress> ee = n.getInetAddresses();
        while (ee.hasMoreElements())
        {
            InetAddress i = (InetAddress) ee.nextElement();
            String currentAddress = i.getHostAddress();
            logger.trace("IP address "+currentAddress+ " found");
            if(!i.isSiteLocalAddress()&&!i.isLoopbackAddress() && validate(currentAddress)){
                ipToReturn = currentAddress;    
            }else{
                System.out.println("Address not validated as public IPv4");
            }

        }
    }

    return ipToReturn;
}

private static final Pattern IPv4RegexPattern = Pattern.compile(
        "^(([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.){3}([01]?\\d\\d?|2[0-4]\\d|25[0-5])$");

public static boolean validate(final String ip) {
    return IPv4RegexPattern.matcher(ip).matches();
}

因为我的系统(像许多其他系统一样)有各种网络接口。inetaddress . getlocalhost()或Inet4Address.getLocalHost()只是返回一个我不需要的网络接口。 因此,我不得不使用这种幼稚的方法。

InetAddress[] allAddresses = Inet4Address.getAllByName("YourComputerHostName");
        InetAddress desiredAddress;
        //In order to find the desired Ip to be routed by other modules (WiFi adapter)
        for (InetAddress address :
                allAddresses) {
            if (address.getHostAddress().startsWith("192.168.2")) {
                desiredAddress = address;
            }
        }
// Use the desired address for whatever purpose.

只是要注意,在这种方法中,我已经知道我想要的IP地址在192.168.2子网中。

如果您的机器是网络的一部分,那么它将获取您的网络的IP地址

try {
    System.out.println(InetAddress.getLocalHost().getHostAddress());
} catch (UnknownHostException e) {
    e.printStackTrace();
}