}

    @Test
    public void test_multipleInstances() {
        // Test creating multiple instances
        SsoLoginException exception1 = new SsoLoginException("Error 1");
        SsoLoginException exception2 = new SsoLoginException("Error 2");
        SsoLoginException exception3 = new SsoLoginException("Error 3", new RuntimeException());

        assertNotSame(exception1, exception2);

import org.codelibs.fess.app.web.base.login.FessLoginAssist.LoginCredentialResolver;
import org.codelibs.fess.app.web.base.login.SpnegoCredential;
import org.codelibs.fess.exception.SsoLoginException;
import org.codelibs.fess.mylasta.action.FessUserBean;
import org.codelibs.fess.mylasta.direction.FessConfig;
import org.codelibs.fess.sso.SsoAuthenticator;
import org.codelibs.fess.sso.SsoResponseType;

            if (StringUtils.isEmpty(nonce) || !nonce.equals(stateData.getNonce())) {
                throw new SsoLoginException("could not validate nonce");
            }
        } catch (final SsoLoginException e) {
            throw e;
        } catch (final Exception e) {
            throw new SsoLoginException("could not validate nonce", e);
        }
    }

    /**
     * Obtains an access token using a refresh token.