如何使用Java显示和存储系统的公共IP地址

Question

I am trying to display and store the Public IP address of a system. I used the following code for the same. ie, I have imported following two statements :

 import java.net.InetAddress;
 import java.net.UnknownHostException;

  try {
        InetAddress iAddress = InetAddress.getLocalHost();            
        String currentIp = iAddress.getHostAddress();
        System.out.println("Current System's IP address is : " +currentIp); 
        } catch (UnknownHostException e) {
              System.out.println("Catch block executed. So IP address is not displayed");
            }

It is displaying the output as :

 "Current System's IP address is : 192.168.1.5"

But my system's public IP address (as checked in https://www.whatismyip.com/ ) is :

 115.107.244.81

So how should I fetch and display the public IP address from .JAVA file?

Answer 1

https://www.whatismyip.com -> which will display the public ip address which will be known to the outside world. If you restart your system then you can see different ip address. Eventhough if you are having a static ip address the website won't show your machine ip address.

Java code output shows your system ip address which will be used for inter communication and that is your actual system ip address. you can verify that in shell/command prompt.

Answer 2

if your are using net from local area network then it always start with 192. something ..

Try to connect with other mode of net connection they it will show the public ip address. Command to get ip address is ipconfig in command prompt in Windows.

Answer 3

ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.currentRequestAttributes();
            HttpServletRequest servletRequest = attributes.getRequest();
            ipAddress = String.valueOf(servletRequest.getSession().getAttribute("clientAddress"));