assertEquals(expectedSize, size);
        verify(negotiationResponse).getTransactionBufferSize();
    }

    @Test
    @DisplayName("Test getTransactionBufferSize returns zero")
    void testGetTransactionBufferSizeZero() {
        // Arrange
        when(negotiationResponse.getTransactionBufferSize()).thenReturn(0);

        // Act
        int size = negotiationResponse.getTransactionBufferSize();

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