java 获取本机ip 异常,使用Java获取本机IP出错 java.net.UnknownHostException

import java.net.InetAddress;

import java.net.NetworkInterface;

import java.net.UnknownHostException;

import java.util.Enumeration;

public class IP {

public static void main(String[] args) throws UnknownHostException {

System.out.println(getLocalHostExactAddress().getHostAddress());

}

public static InetAddress getLocalHostExactAddress() {

try {

InetAddress candidateAddress = null;

Enumeration networkInterfaces = NetworkInterface.getNetworkInterfaces();

while (networkInterfaces.hasMoreElements()) {

NetworkInterface iface = networkInterfaces.nextElement();

// 该网卡接口下的ip会有多个，也需要一个个的遍历，找到自己所需要的

for (Enumeration inetAddrs = iface.getInetAddresses(); inetAddrs.hasMoreElements(); ) {

InetAddress inetAddr = inetAddrs.nextElement();

// 排除loopback回环类型地址(不管是IPv4还是IPv6 只要是回环地址都会返回true)

if (!inetAddr.isLoopbackAddress()) {

if (inetAddr.isSiteLocalAddress()) {

// 如果是site-local地址，就是它了 就是我们要找的

// ~~~~~~~~~~~~~绝大部分情况下都会在此处返回你的ip地址值~~~~~~~~~~~~~

return inetAddr;

}

// 若不是site-local地址 那就记录下该地址当作候选

if (candidateAddress == null) {

candidateAddress = inetAddr;

}

}

}

}

// 如果出去loopback回环地之外无其它地址了，那就回退到原始方案吧

return candidateAddress == null ? InetAddress.getLocalHost() : candidateAddress;

} catch (Exception e) {

e.printStackTrace();

}

return null;

}

}