assertThrows(SmbException.class, () -> {
            validator.validateMessageSize(17 * 1024 * 1024, false);
        });
    }

    @Test
    public void testValidString() throws Exception {
        validator.validateString("normal string", 100, "test");
        validator.validateString(null, 100, "test"); // Null should be allowed
        // Should pass without exception
    }