java - Randomly "shaking" an array to assign new random spots -

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what im trying take array coins[]. , rearrange each coin different position. have far. when though, nothing happens. meaning values stay same. except last one. 1 changes. 

public void shake()  {     (int = 0; < coins.length; i++)     {         int index = coin.random.nextint(coins.length);         coin temp = coins[index];         coins[index] = coins[i];         coins[i] = temp;          system.out.print(coins[i] + ", ");     } }

i instantiate random this:

public static long seed = system.currenttimemillis(); public static random random = new random(seed);

as using swap index swapping current value can edit random number generator generate random numbers between range (say 0 - coins.length) , can change implementation this

public void shake()  {      coin temp;      (int = 0; < coins.length; i++)     {         //int swap = coin.random.nextint(coins.length);         temp = coins[swap];         coins[swap] = coins[i];         coins[i] = temp;          system.out.print(coins[i] + ", ");     } }

for commented line in code check this update random number generator generate numbers between 2 values. each time generate swap(index) between i+1 - coins.length , continue till exhaust array. ensures don't make swap @ index value have displayed. not confident indeed random shuffle in beginning of loop have more choices swap index have sometime later in loop , shake not random. solution in case want strictly implement own shake method without using collections.shuffle @tomek mentioned.


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