java如何获取ip地址

在Java中，可以使用InetAddress类来获取IP地址。

以下是一些示例代码：

获取本机IP地址：

import java.net.InetAddress;public class Main {    public static void main(String[] args) {        try {            InetAddress localhost = InetAddress.getLocalHost();            System.out.println("本机IP地址: " + localhost.getHostAddress());        } catch (Exception e) {            e.printStackTrace();        }    }}

获取指定域名的IP地址：

import java.net.InetAddress;public class Main {    public static void main(String[] args) {        try {            InetAddress address = InetAddress.getByName("www.google.com");            System.out.println("www.google.com 的IP地址: " + address.getHostAddress());        } catch (Exception e) {            e.printStackTrace();        }    }}

注意：InetAddress.getLocalHost()方法可能返回本机的IPv6地址，而不是IPv4地址。如果需要获取IPv4地址，可以使用NetworkInterface类来获取本机的网络接口，然后从中获取IPv4地址。

例如：

import java.net.InetAddress;import java.net.NetworkInterface;import java.util.Enumeration;public class Main {    public static void main(String[] args) {        try {            Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();            while (interfaces.hasMoreElements()) {                NetworkInterface networkInterface = interfaces.nextElement();                Enumeration<InetAddress> addresses = networkInterface.getInetAddresses();                while (addresses.hasMoreElements()) {                    InetAddress address = addresses.nextElement();                    if (!address.isLoopbackAddress() && address.getHostAddress().indexOf(":") == -1) {                        System.out.println("本机IPv4地址: " + address.getHostAddress());                    }                }            }        } catch (Exception e) {            e.printStackTrace();        }    }}