@Override
    public final void writeTimeHHMMSS8(int hour, int minute, int second) {
        int off = this.off;
        int minCapacity = off + 10;
        byte[] bytes = this.bytes;
        if (minCapacity > bytes.length) {
            bytes = grow(minCapacity);
        }
        bytes[off] = (byte) quote;
        IOUtils.writeLocalTime(bytes, off + 1, hour, minute, second);
        bytes[off + 9] = (byte) quote;
        this.off = off + 10;
    }
A faster alternative that is functionally equivalent to Long.expand(i, 0x0F0F_0F0F_0F0F_0F0FL)
core/src/main/java/com/alibaba/fastjson2/JSONWriterUTF8.java