Main.java

package com.company;

import java.util.ArrayList;
import java.util.List;

public class Main {

    public static void main(String[] args) {
        System.out.println(read_vi32bis(write_vi32bis(10)));
    }

    static byte[] write_vi32bis(int data) {
        if ((data >= 0) && (data <= 0b01111111))
            return new byte[] {(byte) data};

        int c = data;
        byte b;

        List<Byte> bytes = new ArrayList<>();
        while (c != 0) {
            b = (byte) (c & 0b01111111);
            c = c >> 7;

            if (c > 0)
                b = (byte) (b | 0b01111111);

            bytes.add(b);
        }

        byte[] byteArray = new byte[bytes.size()];
        for (int index = 0; index < bytes.size(); index++) {
            byteArray[index] = bytes.get(index);
        }

        return byteArray;
    }

	static int read_vi32bis(byte[] bytes) {
        byte b;
        int value = 0;
        int offset = 0;
        boolean hasNext;
        int pos = 0;

        do {
            b = bytes[pos++];
            hasNext = (b & 0b10000000) == 0b10000000;
            value = offset > 0
                    ? (value + ((b & 0b01111111) << offset))
                    : (value + (b & 0b01111111));
            offset += 7;
        } while (hasNext);

        return value;
    }

    static int read_vi32(byte[] bytes) {
        int res = 0;
        for (int i = 0; i < 4; i++) {
            byte b = bytes[i];
            if ((b & 0b10000000) != 0) {
                break;
            }
            res = (res << 7) | (b & 0b01111111);
        }
        return res;
    }

    static byte[] write_vi32(int res) {
        int i = 0;
        byte[] bytes = new byte[4];
        do {
            int res1 = res & 0b01111111;
            res = res >> 7;
            bytes[i] = (byte) (res1 | (res != 0 ? 0b10000000 : 0));
            i++;
        } while (i < 4 && res != 0);

        return bytes;
    }
}