说明

java获取本机所有ip地址，用下面方法是最好的

从JDK1.4开始，Java提供了 NetworkInterface 类。这个类可以得到 本机所有的物理网络接口 和 虚拟机等软件利用本机的物理网络接口创建的逻辑网络接口 的信息

NetworkInterface 可以通过 getNetworkInterfaces 方法来枚举本机所有的网络接口

NetworkInterface 常用方法

getName方法

public String getName()

这个方法用来得到一个网络接口的名称。这个名称就是使用getByName 方法创建NetworkInterface 对象时使用的网络接口名，如eth0 、ppp0 等。

getDisplayName方法

public String getDisplayName()

这个方法可以得到更容易理解的网络接口名，也可以将这个网络接口名称为网络接口别名。在一些操作系统中（如Unix ），getDisplayName 方法和getName 方法的返回值相同，但在Windows 中getDisplayName 方法一般会返回一个更为友好的名字，如 Realtek RTL8139 Family PCI Fast Ethernet NIC 。

getInetAddresses方法

public Enumeration<InetAddress> getInetAddresses()

NetworkInterface 类可以通过getInetAddresse 方法以InetAddress 对象的形式返回和网络接口绑定的所有IP 地址。getInetAddresses 方法的定义如下：

代码

package top.malaoshi.net;

import java.net.*;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;

public class LocalIP {

    public static void main(String[] args) throws SocketException, UnknownHostException {
        try {
            List<String> ips = getIPs();
            for(String ip: ips) {
                System.out.println("本机IP:" + ip);
            }
            List<NetInfo> ipAndBroadcast = getNetInfo();
            for(NetInfo info : ipAndBroadcast){
                System.out.println(info.getIp()+"--"+info.getBroadcast()+"--"+info.getMask());
            }
        } catch (SocketException e) {
            throw new RuntimeException(e);
        }

    }

    public static List<String> getIPs() throws SocketException {
        List<String> ips = new ArrayList<>();
        Enumeration<NetworkInterface> allNetInterfaces = NetworkInterface.getNetworkInterfaces();

        while (allNetInterfaces.hasMoreElements()) {
            NetworkInterface netInterface = allNetInterfaces.nextElement();
            if (netInterface.isLoopback() || netInterface.isVirtual() || !netInterface.isUp()) {

            } else {
                Enumeration<InetAddress> addresses = netInterface.getInetAddresses();
                while (addresses.hasMoreElements()) {
                    InetAddress ip = addresses.nextElement();
                    if (ip != null && ip instanceof Inet4Address) {
                        ips.add( ip.getHostAddress() );
                    }
                }
            }
        }

        return ips;
    }

    /**
     * 获取ip、广播地址、子网掩码
     * @return
     * @throws SocketException
     */
    public static List<NetInfo> getNetInfo() throws SocketException {

        List<NetInfo> ret = new ArrayList<>();
        Enumeration<NetworkInterface> allNetInterfaces = NetworkInterface.getNetworkInterfaces();

        while (allNetInterfaces.hasMoreElements()) {
            NetworkInterface netInterface = allNetInterfaces.nextElement();
            if (netInterface.isLoopback() || netInterface.isVirtual() || !netInterface.isUp()) {

            } else {

                List<InterfaceAddress> list = netInterface.getInterfaceAddresses();
                for( InterfaceAddress interfaceAddress : list) {
                    InetAddress inetAddress = interfaceAddress.getAddress();
                    if (inetAddress != null && inetAddress instanceof Inet4Address) {
                        String ipAddress = inetAddress.getHostAddress();

                        InetAddress broadcast = interfaceAddress.getBroadcast();
                        String broadcastHostAddress = broadcast.getHostAddress();

                        String mask = parseMask(interfaceAddress.getNetworkPrefixLength());

                        NetInfo netInfo = new NetInfo(ipAddress,broadcastHostAddress,mask);
                        ret.add(netInfo);

                    }

                }
            }
        }

        return ret;
    }

    /**
     * 解析子网掩码
     * @param mask
     * @return
     */
    private static String parseMask(short mask){
        StringBuilder maskStr = new StringBuilder();
        int[] maskIp = new int[4];
        for (int i = 0; i < maskIp.length; i++) {
            maskIp[i] = (mask >= 8) ? 255 : (mask > 0 ? (mask & 0xff) : 0);
            mask -= 8;
            maskStr.append(maskIp[i]);
            if (i < maskIp.length - 1) {
                maskStr.append(".");
            }
        }
        return maskStr.toString();
    }

    public static class NetInfo {
        /**
         * ip地址
         */
        private String ip;
        /**
         * 广播地址
         */
        private String broadcast;
        /**
         * 子网掩码
         */
        private String mask;

        public NetInfo(String ip, String broadcast, String mask) {
            this.ip = ip;
            this.broadcast = broadcast;
            this.mask = mask;
        }

        @Override
        public String toString() {
            return "Info{" +
                    "ip='" + ip + '\'' +
                    ", broadcast='" + broadcast + '\'' +
                    ", mask='" + mask + '\'' +
                    '}';
        }

        public String getIp() {
            return ip;
        }

        public void setIp(String ip) {
            this.ip = ip;
        }

        public String getBroadcast() {
            return broadcast;
        }

        public void setBroadcast(String broadcast) {
            this.broadcast = broadcast;
        }

        public String getMask() {
            return mask;
        }

        public void setMask(String mask) {
            this.mask = mask;
        }
    }
}

参考：
https://blog.csdn.net/nianbingsihan/article/details/80265029