assertNull(ex.getMessage());
        assertSame(cause, ex.getCause());
        assertEquals(SMBProtocolDowngradeException.class.getName(), ex.toString());
    }

    @Test
    void assertThrows_capturesExceptionAndMessage() {
        // Arrange
        String msg = "downgrade not allowed";

        // Act & Assert - verify thrown type and message

Shinsuke Sugaya <******@****.***> 1755149504 +0900