}
public void openSession(final String userName, final List<String> roles) {
IsisContext.closeSession();
final LogonFixture logonFixture = new LogonFixture(userName, roles);
final AuthenticationRequestLogonFixture authRequest = new AuthenticationRequestLogonFixture(logonFixture);
final AuthenticationSession authSession = getAuthenticationManager().authenticate(authRequest);
IsisContext.openSession(authSession);
}