Task 3 Alexey Michael

src/main/java/ru/ifmo/cet/javabasics/WarAndPeaceExercise.java

@@ -1,21 +1,36 @@
 package ru.ifmo.cet.javabasics;
 
+import java.io.IOException;
+import java.nio.charset.Charset;
+import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
-
+import java.util.*;
+import java.util.stream.Collectors;
 
 public class WarAndPeaceExercise {
 
-    public static String warAndPeace() {
+    public static String warAndPeace() throws IOException {
         final Path tome12Path = Paths.get("src", "main", "resources", "WAP12.txt");
         final Path tome34Path = Paths.get("src", "main", "resources", "WAP34.txt");
+        final Charset charset = Charset.forName("windows-1251");
+        List<String> string_list = Files.readAllLines(tome12Path, charset);
+        string_list.addAll(Files.readAllLines(tome34Path, charset));
+        List<String> words_list = new ArrayList<>();
+        string_list.stream().map(line -> line.toLowerCase()).map(lowLine -> lowLine.replaceAll("[^a-z\u0430-\u044f]", " ")).
+                map(lowReplaceLine -> Arrays.stream(lowReplaceLine.split(" ")).filter(word->word.length()>=4).collect(Collectors.toList())).forEach(c -> words_list.addAll(c));
 
-        // TODO map lowercased words to its amount in text and concatenate its entries.
-        // TODO Iff word "котик" occurred in text 23 times then its entry would be "котик - 23\n".
-        // TODO Entries in final String should be also sorted by amount and then in alphabetical order iff needed.
-        // TODO Also omit any word with lengths less than 4 and frequency less than 10
+        Map<String,Integer> vocabulary=new LinkedHashMap<>();
+        words_list.forEach(key -> {
+            vocabulary.put(key, vocabulary.containsKey(key) ? vocabulary.get(key) + 1 : 1);
+        });
+        vocabulary.entrySet().removeIf(pair->pair.getValue()<10);
 
-        throw new UnsupportedOperationException();
-    }
+        List<Map.Entry<String, Integer>> sorted_vocabulary = new ArrayList(vocabulary.entrySet());
+        sorted_vocabulary.sort(Map.Entry.comparingByKey());
+        sorted_vocabulary.sort(Map.Entry.<String, Integer>comparingByValue().reversed());
 
-}
+        String res_answer=sorted_vocabulary.stream().map(entry->entry.getKey() + " - " + entry.getValue()).collect(Collectors.joining("\n"));
+        return res_answer;
+    }
+}