How Random is the Random method ?

Question

Hi ,
I have designed this method to read in an array of integers and then to shuffle the integers in the array.
     public int [] shuffle(int [] array){
     Random rand = new Random();
     for (int i = 0 ; i <=1000 ; i ++)
          int x = rand.nextInt(312);
          int y = rand.nextInt(312);
          temp = array[x];
          array[x] = array[y];
          array[y] = temp;
          temp = 0;
     return array;
I then call the method with 10 arrays. The arrays are 312 integers long and the values range from 1 .. 13 . But fairly often I get identical patterns of numbers . I was wondering if it was because of the Random function repeating itself or something I am doing
Thank you for your time
Craig

Answer 1

Ok , Thanks for that .
So basically because my program is runnning so quickly the Systems clock has not updated by the time when the second array goes into the method and so the random numbers generated are the same.
Can anyone suggest a way to solve the problem ? because I can not remove the Random generator from the method.
Thanks Again Craig