Java. InetAddress.getLocalHost returns strange IP

问题

I'm don't understand, why code below prints 0.0.9.229 instead 127.0.0.1. Can anybody tell me, hot to fix that?

String ha = InetAddress.getLocalHost().getHostAddress();
System.out.println(ha);

UPD: Code running on Ubuntu

/etc/hosts

127.0.0.1       localhost
127.0.1.1       2533

回答1:

InetAddress.getLocalHost() doesn't do what most people think that it does. It actually returns the hostname of the machine, and the IP address associated with that hostname. This may be the address used to connect to the outside world. It may not. It just depends on how you have your system configured.

On my windowsbox it gets the machine name and the external ip address. On my linux box it returns hostname and 127.0.0.1 because I have it set so in /etc/hosts

回答2:

The problem is that my hostname will consists only of numbers and could not be resolved. I change my /etc/hostname with characters at first position and problem has solved.

回答3:

Use NetworkInterface to enumerate network interfaces; InetAddress.getLocalHost() always returns loopback.If you want to get all IP's associated with your machine use NetworkInterface then you will get 127.0.0.1 also.

 Enumeration<NetworkInterface> nInterfaces = NetworkInterface.getNetworkInterfaces();

    while (nInterfaces.hasMoreElements()) {
        Enumeration<InetAddress> inetAddresses = nInterfaces.nextElement().getInetAddresses();
        while (inetAddresses.hasMoreElements()) {
            String address = inetAddresses.nextElement().getHostAddress();
            System.out.println(address);
        }
    }

来源：https://stackoverflow.com/questions/18488809/java-inetaddress-getlocalhost-returns-strange-ip

标签

java

localhost

host

inetaddress