// Implementation for retain payload flag
                return false;
            }

            @Override
            public void retainPayload() {
                // Implementation for retaining payload
            }
        };

        // Test the concrete implementation
        concreteBlock.setMid(555L);
        assertEquals(555L, concreteBlock.getMid());

                // Implementation for retain payload flag
                return false;
            }

            @Override
            public void retainPayload() {
                // Implementation for retaining payload
            }
        };

        // Test async functionality
        assertFalse(concreteResponse.isAsync());

        // Test received status
        assertFalse(concreteResponse.isReceived());