Sort an ArrayList of Strings that are numbers

Question

What is the fastest way to sort an ArrayList (in descending/ascending manner) that contains numbers, eg: { \"12\", \"3.5\", \"188\", \"33.03

Answer 1

You need to implement your own comparator, and use it on your list. You have to use BigDecimal, because you can have problems with loss of precision. You can use double, if your numbers are quire small precision.

class MyComparator implements Comparator {

    public int compare(String o1, String o2){
        return new BigDecimal(o1).compareTo(new BigDecimal(o2));
    }

}
...
Collections.sort(list, new MyComparator());