@Override
    public FullBinaryMemcacheResponse replace(ByteBuf content) {
        ByteBuf key = key();
        if (key != null) {
            key = key.retainedDuplicate();
        }
        ByteBuf extras = extras();
        if (extras != null) {
            extras = extras.retainedDuplicate();
        }
        return newInstance(key, extras, content);
    }
@Test
    public void fullReplace() {
        ByteBuf newContent = Unpooled.copiedBuffer("new value", CharsetUtil.UTF_8);
        FullBinaryMemcacheResponse newInstance = response.replace(newContent);
        try {
            assertResponseEquals(response, newContent, newInstance);
        } finally {
            response.release();
            newInstance.release();
        }
    }