Java generating “random” numbers that don't repeat for 2^48 period

Question

Basically I want to generate random numbers that won\'t ever repeat for a very long period (I don\'t want to use a sequence) like for example the LCG that java uses:

Answer 1

You can use Collection.shuffle() for that might be Performance issue..

ArrayList number = new ArrayList();
        for (int i = 0; i < array.size(); ++i) 
            number.add(i);
        Collections.shuffle(number);