Using stream API to set strings all lowercase but capitalize first letter

Question

I have a List<String> and through only using the stream API I was settings all strings to lowercase, sorting them from smallest string to largest and printing them. The issue I'm having is capitalizing the first letter of the string.

Is that something I do through .stream().map()?

public class Main {

    public static void main(String[] args) {

        List<String> list = Arrays.asList("SOmE", "StriNgs", "fRom", "mE", "To", "yOU");
        list.stream()
            .map(n -> n.toLowerCase())
            .sorted((a, b) -> a.length() - b.length())
            .forEach(n -> System.out.println(n));;

    }

}

Output:

me
to
you
some
from
strings

Desired output:

Me
To
You
Some
From
Strings

Answer 1

Something like this should suffice:

 list.stream()
     .map(n -> n.toLowerCase())
     .sorted(Comparator.comparingInt(String::length))
     .map(s -> Character.toUpperCase(s.charAt(0)) + s.substring(1))
     .forEachOrdered(n -> System.out.println(n));

1. note that I've changed the comparator, which is essentially the idiomatic approach to do it.
2. I've added a map operation after sorting to uppercase the first letter.

Answer 2

list.stream()
    .map(s -> s.substring(0, 1).toUpperCase() + s.substring(1).toLowerCase())
    .sorted(Comparator.comparingInt(String::length))
    .forEach(System.out::println);

For readability, the line performing capitalisation should be moved into a method,

public class StringUtils {
    public static String capitalise(String s) {
        return s.substring(0, 1).toUpperCase() + s.substring(1).toLowerCase();
    }
}

so you can refer to it via an eloquent method reference:

list.stream()
    .map(StringUtils::capitalise)
    .sorted(Comparator.comparingInt(String::length))
    .forEach(System.out::println);