random number generator for special characters

Question

I am trying to generate random number with special characters

what i do for simple integers is

Random randomGenerator = new Random();
int randomNumber = randomGenerator.nextInt();

what can i do to get some thing like this in my random numbers

String salt = "Random$SaltValue#WithSpecialCharacters12@$@4&#%^$*";

thanks

Rong Nguyen · Accepted Answer · 2014-07-16T10:40:45.623

9

You can try the following:

Init your special characters set.
Create a StringBuilder to contain your desired string.
Get random character and append to StringBuilder object.

The code:

final String alphabet = "<Your special characters>";
final int N = alphabet.length();
Random rd = new Random();
int iLength = <length you want>;
StringBuilder sb = new StringBuilder(iLength);
for (int i = 0; i < iLength; i++) {
    sb.append(alphabet.charAt(rd.nextInt(N)));
}

edited Jul 16 '14 at 10:40

answered Jun 05 '13 at 08:00

Rong Nguyen

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1

A `StringBuilder` or a fixed length character array would make this more efficient. – Duncan Jones Jun 05 '13 at 08:35
@Duncan Jones You're right, thank for your advice ! – Rong Nguyen Jun 05 '13 at 08:45

score 7 · Answer 2 · answered Jun 05 '13 at 07:59

7

If you're happy to use third-party libraries, you may find the RandomStringUtils class from Apache Commons Lang helpful.

You can specify the allowed set of characters (or use all available characters).

answered Jun 05 '13 at 07:59

Duncan Jones

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score 2 · Answer 3 · answered Jun 05 '13 at 08:04

import java.util.*;

class Test {

  static Random r = new Random();

  static char[] choices = ("abcdefghijklmnopqrstuvwxyz" +
      "ABCDEFGHIJKLMNOPQRSTUVWXYZ" +
      "01234567890" +
      "$#_").toCharArray();

  public static String getSalt(int len) {
    StringBuilder salt = new StringBuilder(len);
    for (int i = 0; i<len; ++i)
      salt.append(choices[r.nextInt(choices.length)]);
    return salt.toString();
  }

  public static void main(String[]_) {
    System.out.println(getSalt(32));
  }
}

Example output: vdq5L6bANFIQH_MUyKyZxLcOkJeB3uJ1

score 2 · Answer 4 · edited May 31 '18 at 22:54

2

If you want to generate this http://en.wikipedia.org/wiki/Special_characters special characters then try this

char c = (char) (randomGenerator.nextInt(0xB4 - 21 + 1) + 21);

edited May 31 '18 at 22:54

Jason Aller

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answered Jun 05 '13 at 08:09

Evgeniy Dorofeev

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PSR · Answer 5 · 2013-06-05T08:13:37.160

1

String alphabet = "here specify all the characters you want";
    final int N = alphabet.length();

    Random r = new Random();
    String finalStr= "";

    for (int i = 0; i < 50; i++) {
       finalStr+=alphabet.charAt(r.nextInt(N));
    }

edited Jun 05 '13 at 08:13

answered Jun 05 '13 at 07:59

PSR

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random number generator for special characters

5 Answers5