Java Algorithms How to - Generate random values that not repeat

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Question

We would like to know how to generate random values that not repeat.

Answer

import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Random;
import java.util.Set;
//from   w  w  w  . j a  v a 2s .  c  o m
public class Main {
  public static void main(String[] args) {
    Random random = new Random();
    Set<Integer> set = new HashSet<Integer>();
    while (set.size() < 5) {
      set.add(random.nextInt());
    }
    List<Integer> result = new ArrayList<Integer>(set);
    System.out.println(result);
  }
}

The code above generates the following result.

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