assertEquals(0, opnum1, "All calls should return 0");
        }

        @Test
        @DisplayName("getOpnum should return 0 for parameterized constructor")
        void testGetOpnumWithParameterizedConstructor() throws Exception {
            // Given
            when(mockHandle.getMaxXmit()).thenReturn(2048);
            when(mockHandle.getMaxRecv()).thenReturn(2048);