@Override
    public Object set(int index, Object element) {
        if (index == -1) {
            list.add(element);
            return null;
        }

        if (list.size() <= index) {
            for (int i = list.size(); i < index; ++i) {
                list.add(null);
            }
            list.add(element);
            return null;
        }

        return list.set(index, element);
    }
Returns a byte value at the specified location in this {@link com.alibaba.fastjson2.JSONArray}.

@param index index of the element to return
@return byte
@throws NumberFormatException If the value of get is {@link String} and it contains no parsable byte
@throws JSONException Unsupported type conversion to byte value
@throws IndexOutOfBoundsException if the index is out of range {@code (index < 0 || index >= size())}
fastjson1-compatible/src/main/java/com/alibaba/fastjson/JSONArray.java