public final Object ensureCapacity(int minCapacity) {
        byte[] bytes = this.bytes;
        if (minCapacity >= bytes.length) {
            this.bytes = bytes = Arrays.copyOf(bytes, newCapacity(minCapacity, bytes.length));
        }
        return bytes;
    }
A faster alternative that is functionally equivalent to Long.expand(i, 0x0F0F_0F0F_0F0F_0F0FL)
core/src/main/java/com/alibaba/fastjson2/JSONWriterUTF8.java