when(mock.getSubject()).thenReturn(subject);
            doNothing().when(mock).login();
        })) {
            KerberosCredentials credentials = new KerberosCredentials(LOGIN_CONTEXT_NAME);
            assertNotNull(credentials.getSubject());
            assertEquals(subject, credentials.getSubject());
        }
    }

    /**
     * Test constructor when login fails.

        this.cachedSubject = null;
    }

    @Override
    public synchronized Subject getSubject() {
        if (this.cachedSubject != null) {
            return this.cachedSubject;
        }

        try {
            log.debug("Logging on");
            LoginContext lc;

            Subject ps = super.getSubject();

            if (this.configuration != null) {

     */
    public KerberosCredentials(String loginContextName) throws LoginException {
        LoginContext lc = new LoginContext(loginContextName);
        lc.login();
        this.subject = lc.getSubject();
    }

    /**
     * Retrieves all Kerberos keys from the authenticated subject.
     *
     * @return array of KerberosKey objects
     */
    public KerberosKey[] getKeys() {

    /**
     * Get the security subject associated with these credentials.
     * @return subject associated with the credentials
     */
    Subject getSubject();

    /**
     * Refresh the credentials.
     * @throws CIFSException if refresh fails
     */
    void refresh() throws CIFSException;

    }

    /**
     * Sets an object in the current request attributes.
     *
     * @param name The attribute name
     * @param value The attribute value
     */
    public static void setObject(final String name, final Object value) {
        LaRequestUtil.getOptionalRequest().ifPresent(req -> req.setAttribute(name, value));
    }

    /**
     * Gets an object from the current request attributes.
     *

                throws SmbException {
            // Not used within these tests
            throw new SmbException("not used in tests");
        }

        @Override
        public Subject getSubject() {
            return null; // not relevant for renew() behavior
        }

        @Override
        public void refresh() throws CIFSException {
            // no-op for tests
        }

        @Override