Java获取IPv4地址

关于这一点link https://stackoverflow.com/questions/8083479/java-getting-my-ip-address使用提供的代码来生成 IP 地址。

String ip;
    try {
       Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();
        while (interfaces.hasMoreElements()) {
            NetworkInterface iface = interfaces.nextElement();
            // filters out 127.0.0.1 and inactive interfaces
            if (iface.isLoopback() || !iface.isUp())
                continue;

            Enumeration<InetAddress> addresses = iface.getInetAddresses();
            while(addresses.hasMoreElements()) {
                InetAddress addr = addresses.nextElement();
                ip = addr.getHostAddress();
                System.out.println(iface.getDisplayName() + " " + ip);
            }
        }
    } catch (SocketException e) {
        throw new RuntimeException(e);
    }

我已经实现了获取 IP 地址的确切代码，但它同时提供了 IPv4 和 IPv6 地址。以下是产生的值。

Qualcomm Atheros AR5BWB222 Wireless Network Adapter 192.168.1.5
Qualcomm Atheros AR5BWB222 Wireless Network Adapter fe80:0:0:0:a874:xxxx:xxxx:9150%wlan0

（IPv6 地址经过编辑）

有什么方法可以让我只能获取 IPv4 值而不是两者都获取吗？

您可以检查该类型addr对象来查看它是否是一个Inet4Address or an Inet6Address实例。

例如：

String ip;
try {
    Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();
    while (interfaces.hasMoreElements()) {
        NetworkInterface iface = interfaces.nextElement();
        // filters out 127.0.0.1 and inactive interfaces
        if (iface.isLoopback() || !iface.isUp())
            continue;

        Enumeration<InetAddress> addresses = iface.getInetAddresses();
        while(addresses.hasMoreElements()) {
            InetAddress addr = addresses.nextElement();

            // *EDIT*
            if (addr instanceof Inet6Address) continue;

            ip = addr.getHostAddress();
            System.out.println(iface.getDisplayName() + " " + ip);
        }
    }
} catch (SocketException e) {
    throw new RuntimeException(e);
}