Sort List<List<Integer>> based on the Integer in the second index of the inner List<Integer>?

Imagine I have the following input:

[[5,3,6,7],[2,1,6,3],[3,2,6,3],[5,4,4,3]]

How could I sort it based on the second number of each list, so that I have the following: (because 1 < 2 < 3 < 4)

[[2,1,6,3],[3,2,6,3],[5,3,6,7],[5,4,4,3]]

I imagine you can do something with Streams, but I haven't quite figured it out.

Well, this is very simple. Actually you can look at list sorting and custom comparator.

public static void sortBySecondIndex(List<List<Integer>> data) {
    data.sort(Comparator.comparingInt(one -> one.get(1)));        
}

list.sort((a, b) -> a.get(1).compareTo(b.get(1)));