获取本地IP工具类

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方式一：InetAddress工具类

public static String getLocalIP() {
    try {
        return InetAddress.getLocalHost().getHostAddress();
    } catch (UnknownHostException e) {
        throw new RuntimeException(e);
    }
}

存在问题： 如果在虚拟机或Docker容器上执行可能返回127.0.0.1；

方式二：使用网卡地址

/**
 * 直接根据第一个网卡地址作为其内网ipv4地址，避免返回 127.0.0.1
 *
 * @return
 */
public static String getLocalIpByNetcard() {
    try {
        for (Enumeration<NetworkInterface> e = NetworkInterface.getNetworkInterfaces(); e.hasMoreElements(); ) {
            NetworkInterface item = e.nextElement();
            for (InterfaceAddress address : item.getInterfaceAddresses()) {
                if (item.isLoopback() || !item.isUp()) {
                    continue;
                }
                if (address.getAddress() instanceof Inet4Address) {
                    Inet4Address inet4Address = (Inet4Address) address.getAddress();
                    return inet4Address.getHostAddress();
                }
            }
        }
        return InetAddress.getLocalHost().getHostAddress();
    } catch (SocketException | UnknownHostException e) {
        throw new RuntimeException(e);
    }
}

参考：

1. https://liuyueyi.github.io/hexblog/2018/07/09/170709-Java实现获取本机Ip工具类/