Sorting ArrayList of Arraylist in java

Question

I have an ArrayList of ArrayList of String.

In Outer ArrayList on each index each Inner ArrayList has four items have four parameters.

1. Contacts Id

Answer 1

Use the following Comparator:

class MyComparator implements Comparator> {
    private static int indexToCompare = 1;
    @Override
    public int compare(ArrayList o1, ArrayList o2) {
        return o1.get(indexToCompare).compareTo(o2.get(indexToCompare));
    }

}

Here indexToCompare is the index of the arraylist which corresponds to Contact Name. In your case "1"