Question

I’d like to know how I can code a Java program that knows which Windows application is in focus. I can have many windows open but I want to know the one that’s being used (like Google Chrome right now as I’m typing this).

I don’t need to change anything in the window or application, just need to know its name.

Answer 1

I’m afraid there’s no java api for that. JVM does not know anything about the windows it does not manage. You’ll probably have to use JNI and call this function

[DllImport("user32.dll")]
static extern IntPtr GetForegroundWindow();

MSDN link

PS. THere is a GetWindowText function that you might want to use if you need to grab the title of the window.

This post has JNI examples that might be helpful for you.