How to get Windows username in Java?

Question

So what I am trying to do is let my Java find the user's name that windows is logged in with, so when I would say such a method, it would return the users name, like I use it in the User called Noah, java would return "Noah" and if I were on the user Amanda, Java would return "Amanda". How would I do this?

Answer 1

Lookup the system property "user.name".

String username = System.getProperty("user.name");

• System Properties
• System.getProperty

Demonstration: Main.java

public class Main {
   public static void main(String[] args) {
      System.out.println(System.getProperty("user.name"));
   }
}

Output:

c:\dev\src\misc>javac Main.java

c:\dev\src\misc>java Main
rgettman

c:\dev\src\misc>

Answer 2

Try:

String userName = System.getProperty("user.name");

or

String userName = new com.sun.security.auth.module.NTSystem().getName()

Answer 3

Two ways

1. System.getProperty("user.name");

2. System.getenv("USERNAME");

Both are good for any OS

Answer 4

NTSystem.getName() also returns SYSTEM when the app runs on a windows service. There is no means to get the username with NTSystem when the app is running on a windows service