// Initially, rawPayload should be null
        assertNull(message.getRawPayload(), "rawPayload should be null initially");

        // Set a new payload and verify
        byte[] payload1 = "test_payload_1".getBytes();
        message.setRawPayload(payload1);
        assertArrayEquals(payload1, message.getRawPayload(), "getRawPayload should return the set payload");

        // Set another payload and verify

            this.retainPayload = true;
        }

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

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

        @Override
        public void setRawPayload(byte[] rawPayload) {
            this.rawPayload = rawPayload;
        }
    }

    /**

     */
    boolean isRetainPayload();

    /**
     * Gets the raw payload of the message.
     *
     * @return the raw response message
     */
    byte[] getRawPayload();

    /**
     * Sets the raw payload of the message.
     *
     * @param rawPayload the raw message payload to set
     */
    void setRawPayload(byte[] rawPayload);

            this.retainPayload = retainPayload;
        }

        @Override
        public void setRawPayload(byte[] payload) {
            this.rawPayload = payload;
        }

        public byte[] getRawPayload() {
            return rawPayload;
        }

        // Helper method to set credit since parent's setter is final
        public void setCreditForTest(int credit) {
            setCredit(credit);
        }

        public void retainPayload() {
        }

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

        @Override
        public byte[] getRawPayload() {
            return null;
        }

        @Override
        public void setRawPayload(byte[] rawPayload) {
        }
    }

            return true; // Default to successful verification
        }

        public void setRetainPayload(boolean retain) {
            this.retainPayload = retain;
        }

        public byte[] getRawPayload() {
            return rawPayload;
        }

        // Expose headerStart for testing
        public int getHeaderStart() {
            return headerStart;
        }
    }

    /**

            @Override
            public void setRawPayload(byte[] rawPayload) {
                // Implementation for raw payload
            }

            @Override
            public byte[] getRawPayload() {
                // Implementation for getting raw payload
                return null;
            }

            @Override
            public boolean isRetainPayload() {

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

    /**
     * {@inheritDoc}
     *
     * @see jcifs.util.transport.Response#getRawPayload()
     */
    @Override
    public byte[] getRawPayload() {
        return this.rawPayload;
    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.util.transport.Response#setRawPayload(byte[])
     */

            @Override
            public void setRawPayload(byte[] rawPayload) {
                // Implementation for raw payload
            }

            @Override
            public byte[] getRawPayload() {
                // Implementation for getting raw payload
                return null;
            }

            @Override
            public boolean isRetainPayload() {

        @Override
        public boolean verifySignature(byte[] buffer, int i, int size) {
            // Mock implementation
            return true;
        }

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

        @Override
        public void retainPayload() {
            // Mock implementation - do nothing
        }

        @Override