Completable Futures

Problem:
Process concurrently all the files in a directory tree.
The files store integers, separated by line endings.

Bibliography:
http://www.baeldung.com/java-completablefuture

My solution:

	package parallelStreamsOfIntegers;
	import java.io.BufferedReader;
	import java.io.File;
	import java.io.FileNotFoundException;
	import java.io.FileReader;
	import java.io.IOException;
	import java.nio.file.Files;
	import java.nio.file.Path;
	import java.nio.file.Paths;
	import java.util.ArrayList;
	import java.util.List;
	import java.util.concurrent.CompletableFuture;
	import java.util.stream.Collectors;
	import java.util.stream.Stream;
	public class TestWithCompletableFuture {
	public static void main(String[] args) {
	List<CompletableFuture<Integer>> futures = new ArrayList<>();
	try(Stream<Path> paths = Files.walk(Paths.get("D:\\JavaInterviewExercises\\parallelStreamsOfIntegers\\data"))) {
	paths.forEach(filePath -> {
	if (Files.isRegularFile(filePath)) {
	System.out.println(filePath);
	futures.add(CompletableFuture.supplyAsync(() -> {
	int sum = 0;
	File file = new File(filePath.toString());
	try (BufferedReader reader = new BufferedReader(new FileReader(file))){
	String text = null;
	while ((text = reader.readLine()) != null) {
	sum += (Integer.parseInt(text));
	System.out.println(text);
	}
	}
	catch (FileNotFoundException e) {
	System.out.println("I can't find this file!!!");
	}
	catch (IOException e){
	e.printStackTrace();
	}
	return sum;
	}));
	}
	});
	} catch (IOException e1) {
	// TODO Auto-generated catch block
	e1.printStackTrace();
	}
	Integer combined = futures.stream()
	.map(CompletableFuture::join)
	.mapToInt(i -> i)
	.sum();
	System.out.println(combined);
	}
	}

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