public void handleRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/plain;charset=UTF-8");
final PrintWriter writer = response.getWriter();
AbstractGroups grps = groupsSupplier.determineGroups(request);
if(grps == null) {
writer.println("Did not determine any groups");
} else {
final StringBuilder sb = new StringBuilder();
grps.appendTestGroups(sb, '\n');
writer.print(sb.toString());
}
}