import java.util.List;
import java.util.regex.MatchResult;
import java.util.regex.Pattern;
import java.util.stream.*;


public class Main {
	public static void main(String[] args) {
		List<String> matches = 
				Pattern.compile("\\d+")
					    .matcher("123-8-90")
					    .results()
					    .flatMap(mr -> IntStream.rangeClosed(1, mr.groupCount())
        .mapToObj(mr::group))
					    .collect(Collectors.toList());

			System.out.println(matches);// [123, 8, 90]
	}
}