java - Java 的 IP 地址

Question

我如何获得用户的 IP 地址？

InetAddress ip;
try {

 ip = InetAddress.getLocalHost();
 System.out.println("Current IP address : " + ip.getHostAddress());

} catch (UnknownHostException e) {

e.printStackTrace();

 }

返回:127.0.0.1

我知道那不是我的 IP。这是我的本地 IP 地址。如何使用 java.. 获取用户 IP？

Answer 1

最短的方法是:

try {
InetAddress thisIp =InetAddress.getLocalHost();
System.out.println("IP:"+thisIp.getHostAddress());
}
catch(Exception e) {
e.printStackTrace();
}

但是 getLocalHost 文档说:

If there is a security manager, its checkConnect method is called with the local host name and -1 as its arguments to see if the operation is allowed. If the operation is not allowed, an InetAddress representing the loopback address is returned.

在某些情况下，InetAddress.getLocalHost() 不会查询您的接口(interface)，它只是返回常量 127.0.0.1(对于 IPv4))

我认为 NetworkInterface.getNetworkInterfaces 是您枚举所有可能性所需要的。这是一个不显示虚拟地址但适用于“主”接口(interface)的示例:

import java.net.*;
import java.util.*;

public class Test
{
    public static void main(String[] args)
        throws Exception // Just for simplicity
    {
        for (Enumeration<NetworkInterface> ifaces = 
               NetworkInterface.getNetworkInterfaces();
             ifaces.hasMoreElements(); )
        {
            NetworkInterface iface = ifaces.nextElement();
            System.out.println(iface.getName() + ":");
            for (Enumeration<InetAddress> addresses =
                   iface.getInetAddresses();
                 addresses.hasMoreElements(); )
            {
                InetAddress address = addresses.nextElement();
                System.out.println("  " + address);
            }
        }
    }
}

或者:

尝试使用这个(第一个输出应该是 PC 名称后的 IP):

    InetAddress[] localaddr;

    String computername = null;

    try {
        computername = InetAddress.getLocalHost().getHostName();//get pc name
    } catch (UnknownHostException ex) {
        ex.printStackTrace();
    }

    System.out.println(computername);

    try {
        localaddr = InetAddress.getAllByName(computername);
        for (int i = 0; i < localaddr.length; i++) {
            System.out.println("\n" + localaddr[i].getHostAddress());
        }
    } catch (UnknownHostException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

引用资料:

• IP Address not obtained in java
• http://www.roseindia.net/java/java-get-example/get-ip-address.shtml