How to random java string array , that each array will be true random?

Question

i have java string array which looks like this :

String [] cards = {"c1","c2","c3", , , , , , ,, , "c45"};

so i have there 45 elements , now i like to rendom them each time so it will be :

int[] cards2  = Arrays.copyOf(cards , cards .length);
random(cards2);

how should be the random function look like ?

so if i run say 10 + random function on the same orderd array it will never be the same result — user63898, Jan 07 '16 at 18:45

score 3 · Accepted Answer · answered Jan 07 '16 at 17:54

3

You can use

Collections.shuffle(Arrays.asList(cards));

answered Jan 07 '16 at 17:54

Mohammed Aouf Zouag

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is it good random function , if i run it 10 times each time it will be random ? – user63898 Jan 07 '16 at 18:10

score 1 · Answer 2 · answered Jan 07 '16 at 18:11

You can use this if you want to copy to a new array.

public String[] randome(String[] arr) {
   Random rgen = new Random();

   String[] randArray = new String[arr.length];
    System.arraycopy(arr, 0, randArray, 0, arr.length);

   for (int i = 0; i < randArray.length; i++) {
    int randIn = rgen.nextInt(randArray.length);
    String temp = randArray[i];
    randArray[i] = randArray[randIn];
    randArray[randIn] = temp;
    }

    return randArray;
 }

How to random java string array , that each array will be true random?

2 Answers2