/** Returns the client window under the specified root subwindow. */
private static long findClientWindow(long window) {
if (XlibUtil.isTrueToplevelWindow(window)) {
return window;
}
Set<Long> children = XlibUtil.getChildWindows(window);
for (Long child : children) {
long win = findClientWindow(child);
if (win != 0) {
return win;
}
}
return 0;
}
