private static int appendByte(byte[] dst, int offset, long value) {
        if (value == 0) {
            return offset;
        }
        dst[offset] = (byte) value;
        return offset + 1;
    }
Appends a byte if it's not a leading zero.
core/src/main/java/com/linecorp/armeria/server/file/DefaultEntityTagFunction.java