import java.util.concurrent.ThreadLocalRandom;

private static final String AB = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

  public int getRandomInt() {

    return ThreadLocalRandom.current().nextInt(10000, 100000);

  }

  public String getRandomString(int length) {

    StringBuilder sb = new StringBuilder(length);

    for (int i = 0; i < length; i++) {

      sb.append(AB.charAt(ThreadLocalRandom.current().nextInt(AB.length())));

    }

    return sb.toString();

  }