// Happy path: default constructor creates an exception with no message/cause
    @Test
    @DisplayName("Default ctor: null message/cause and success status")
    void defaultConstructor_hasNullMessageAndCause_andDefaultStatus() {
        // Arrange & Act
        SMBSignatureValidationException ex = new SMBSignatureValidationException();

        // Assert

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