public static void main(String[] args) {

        int i ,counter;
        //int arr[] = null;
        ArrayList<Integer> arr = new ArrayList<Integer>();
        for(counter=101 ; counter <999;counter++){
            boolean check = true ;
            for(i=2;i<counter;i++){
                if(counter%i == 0){
                    check = false;
                    break;
                }

            }
            if(check){

                for(int index = 0;index<=arr.size();index++){
                    arr.add(counter);
                }
        }

        }


        System.out.println(arr.get(arr.size()-1));
        }

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
    at java.util.Arrays.copyOf(Unknown Source)
    at java.util.Arrays.copyOf(Unknown Source)
    at java.util.ArrayList.grow(Unknown Source)
    at java.util.ArrayList.ensureExplicitCapacity(Unknown Source)
    at java.util.ArrayList.ensureCapacityInternal(Unknown Source)
    at java.util.ArrayList.add(Unknown Source)
    at Prime.main(Prime.java:23)