Java Algorithms How to - Generate random numbers String

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Question

We would like to know how to generate random numbers String.

Answer

//w w  w. j  a  v  a  2s .  c om
public class Main {
  static char digits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };

  public static char randomDecimalDigit() {
    return digits[(int) Math.floor(Math.random() * 10)];
  }

  public static String randomDecimalString(int ndigits) {
    StringBuilder result = new StringBuilder();
    for (int i = 0; i < ndigits; i++) {
      result.append(randomDecimalDigit());
    }
    return result.toString();
  }

  public static void main(String[] args) {
    System.out.println(randomDecimalString(24));
  }
}

The code above generates the following result.

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