|
public static Map<Integer, Long> countLetters(String filename) throws IOException {
|
|
return Files.lines(Paths.get(filename))
|
|
.flatMapToInt(String::chars)
|
|
.filter(Character::isLetter)
|
|
.boxed()
|
|
.collect(Collectors.groupingBy(Function.identity(), Collectors.counting()));
|
|
}
|