task1924/Solution

package com.javarush.task.task19.task1924;

import java.io.*;
import java.util.*;
import java.util.regex.*;
import java.util.stream.Collectors;

public class Solution {

    public static Map<Integer, String> map = new HashMap<Integer, String>();

    static {
        map.put(0, "ноль");
        map.put(1, "один");
        map.put(2, "два");
        map.put(3, "три");
        map.put(4, "четыре");
        map.put(5, "пять");
        map.put(6, "шесть");
        map.put(7, "семь");
        map.put(8, "восемь");
        map.put(9, "девять");
        map.put(10, "десять");
        map.put(11, "одиннадцать");
        map.put(12, "двенадцать");
    }

    public static void main(String[] args) throws IOException {
        List<String> content = readFile();
        List<String> contentWithNumbersSpelled = replaceLines(content);
        printList(contentWithNumbersSpelled);
    }

    private static List<String> readFile() throws IOException {
        try (BufferedReader filenameReader = new BufferedReader(new InputStreamReader(System.in));
             BufferedReader fileReader = new BufferedReader(new FileReader(filenameReader.readLine()))) {
            return fileReader.lines().collect(Collectors.toList());
        }
    }

    private static List<String> replaceLines(List<String> content) {
        List<String> list = content.stream()
                                   .map(Solution::spellNumbers)
                                   .collect(Collectors.toList());
        return list;
    }

    private static String spellNumbers(String line) {
        Pattern pattern = Pattern.compile("\\b([0-9]|1[0-2])\\b");
        Matcher matcher = pattern.matcher(line);
        StringBuffer lineReplacer = new StringBuffer(line.length());
        while (matcher.find()){
            String toReplace = matcher.group();
            String replacement = map.get(Integer.valueOf(toReplace));
            matcher.appendReplacement(lineReplacer, replacement);
        }
        matcher.appendTail(lineReplacer);
        return String.valueOf(lineReplacer);
    }

    private static void printList(List<String> lines) {
        lines.forEach(System.out::println);
    }
}