In Java 8:
public static void main(final String[] args) throws IOException {
final List<double[]> row = new ArrayList<double[]>();
row.add(new double[]{10.0, 5.0, 200.3});
row.add(new double[]{9.1, 1.4, 3.3});
row.add(new double[]{9.1, 1.4, 3.3});
final List<double[]> sorted = row.stream().
sorted((l, r) -> Double.compare(l[2], r[2])).
collect(Collectors.toList());
}
Or, if you want to sort in place:
row.sort((l, r) -> Double.compare(l[2], r[2]));