byte[] payload = new byte[] { 1, 2, 3, 4, 5 };

            assertNull(testBlock.getRawPayload());
            assertFalse(testBlock.isRetainPayload());

            testBlock.retainPayload();
            assertTrue(testBlock.isRetainPayload());

            testBlock.setRawPayload(payload);
            assertArrayEquals(payload, testBlock.getRawPayload());
        }
    }

    @Nested

     */
    public final int getCreditCharge() {
        return this.creditCharge;
    }

    @Override
    public void retainPayload() {
        this.retainPayload = true;
    }

    @Override
    public boolean isRetainPayload() {
        return this.retainPayload;
    }

    @Override
    public byte[] getRawPayload() {
        return this.rawPayload;
    }

    @Override

     */
    @Override
    public boolean isRetainPayload() {
        return this.retainPayload;
    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.util.transport.Response#retainPayload()
     */
    @Override
    public void retainPayload() {
        this.retainPayload = true;
    }

    /**
     * {@inheritDoc}
     *

        }

        @Override
        public void reset() {
        }

        // Message interface methods (from jcifs.util.transport.Message)
        @Override
        public void retainPayload() {
        }

        @Override
        public boolean isRetainPayload() {
            return false;
        }

        @Override
        public byte[] getRawPayload() {

            public boolean isRetainPayload() {
                // Implementation for retain payload flag
                return false;
            }

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

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

            public boolean isRetainPayload() {
                // Implementation for retain payload flag
                return false;
            }

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

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

        @Test
        @DisplayName("Should retain payload when requested")
        void testRetainPayload() {
            assertFalse(testMessage.isRetainPayload());
            testMessage.retainPayload();
            assertTrue(testMessage.isRetainPayload());
        }

        @Test
        @DisplayName("Should get and set raw payload")
        void testRawPayload() {