boolean result = chain.changePassword(null, "password");

        assertFalse(result);
        assertEquals(1, chain.changePasswordCalls.size());
        assertNull(chain.changePasswordCalls.get(0).getKey());
        assertEquals("password", chain.changePasswordCalls.get(0).getValue());
    }

    // Test changePassword with null password
    @Test
    public void test_changePassword_nullPassword() {

        final String username = fessConfig.getFesenUsername();
        final String password = fessConfig.getFesenPassword();
        if (StringUtil.isNotBlank(username) && StringUtil.isNotBlank(password)) {
            builder.put(Constants.FESEN_USERNAME, username);
            builder.put(Constants.FESEN_PASSWORD, password);
        }
        final String authorities = fessConfig.getFesenHttpSslCertificateAuthorities();

/**
 * @author FreeGen
 */
public class UserBhv extends BsUserBhv {

    private static final String ROLES = "roles";
    private static final String GROUPS = "groups";
    private static final String PASSWORD = "password";
    private static final String NAME = "name";

    private String indexName = null;

    @Override
    protected String asEsIndex() {
        if (indexName == null) {

            }, validationErrorLambda);
        });
    }

    /**
     * Adds a password validation error message to the messages object based on the error key.
     *
     * @param messages the FessMessages object to add the error to
     * @param errorKey the error key identifying the type of password validation error
     */

        assertEquals("\\2a\\29\\28uid=\\2a\\29\\29\\28|\\28uid=\\2a", LdapUtil.escapeValue("*)(uid=*))(|(uid=*"));

        // Test complex injection: admin)(&(password=*))
        assertEquals("admin\\29\\28&\\28password=\\2a\\29\\29", LdapUtil.escapeValue("admin)(&(password=*))"));
    }

    @Test
    public void test_escapeValue_allSpecialCharsInSequence() {
        assertEquals("\\5c\\2a\\28\\29\\00", LdapUtil.escapeValue("\\*()\0"));

        TermQueryBuilder builder = regTermQ("password", password);
        if (opLambda != null) {
            opLambda.callback(builder);
        }
    }

    public void setPassword_NotEqual(String password) {
        setPassword_NotTerm(password, null);
    }

    public void setPassword_NotTerm(String password) {
        setPassword_NotTerm(password, null);

        ComponentUtil.getLdapManager().delete(user);
    }

    @Override
    public boolean changePassword(final String username, final String password) {
        final boolean changed = ComponentUtil.getLdapManager().changePassword(username, password);
        return !changed || ComponentUtil.getFessConfig().isLdapAdminSyncPassword();
    }

    @Override
    public User load(final User user) {

            final String username = userCredential.getUser();
            final String password = userCredential.getPassword();
            if (!fessConfig.isAdminUser(username)) {
                final OptionalEntity<FessUser> ldapUser = ComponentUtil.getLdapManager().login(username, password);
                if (ldapUser.isPresent()) {
                    return ldapUser;
                }
            }

        private final String password;

        public TestLoginCredential(String username, String password) {
            this.username = username;
            this.password = password;
        }

        public String getUsername() {
            return username;
        }

        public String getPassword() {
            return password;
        }
    }

     * Authenticates a user with the specified username and password against LDAP.
     *
     * @param username the username for authentication
     * @param password the password for authentication
     * @return an optional containing the authenticated user if successful, empty otherwise
     */
    public OptionalEntity<FessUser> login(final String username, final String password) {
        // Add defensive null/blank checks