Get headers of non-Java windows in Java

Question

Window.getWindows(); 

Does not get all open windows, only java. Is there any way to get all windows opened by the operating system. I am creating a java taskbar.

Answer 1

There is no solution using the Java kernel, but the problem can be solved using JNI or, for an easier time, JNA. As noted in the comments, no solution (which I know) will be platform independent.

For example, this demo program uses JNA to list all Windows with a title on the Windows platform, but will also include windows that are not top-level windows or even visible windows:

 import java.util.ArrayList; import java.util.List; import com.sun.jna.Native; import com.sun.jna.Pointer; import com.sun.jna.win32.StdCallLibrary; public class EnumAllWindowNames { static interface User32 extends StdCallLibrary { User32 INSTANCE = (User32) Native.loadLibrary("user32", User32.class); interface WNDENUMPROC extends StdCallCallback { boolean callback(Pointer hWnd, Pointer arg); } boolean EnumWindows(WNDENUMPROC lpEnumFunc, Pointer userData); int GetWindowTextA(Pointer hWnd, byte[] lpString, int nMaxCount); Pointer GetWindow(Pointer hWnd, int uCmd); } public static List<String> getAllWindowNames() { final List<String> windowNames = new ArrayList<String>(); final User32 user32 = User32.INSTANCE; user32 .EnumWindows(new User32.WNDENUMPROC() { @Override public boolean callback(Pointer hWnd, Pointer arg) { byte[] windowText = new byte[512]; user32.GetWindowTextA(hWnd, windowText, 512); String wText = Native.toString(windowText).trim(); if (!wText.isEmpty()) { windowNames.add(wText); } return true; } }, null); return windowNames; } public static void main(String[] args) { List<String> winNameList = getAllWindowNames(); for (String winName : winNameList) { System.out.println(winName); } } }