Coverage Summary for Class: WordCountService (io.github.mkuchin.service.word)

Class	Class, %	Method, %	Line, %
WordCountService	100% (1/ 1)	100% (6/ 6)	100% (20/ 20)
1 package io.github.mkuchin.service.word;
2 
3 import io.github.mkuchin.model.WordCountVO;
4 
5 import java.util.Arrays;
6 import java.util.LinkedHashMap;
7 import java.util.List;
8 import java.util.Map;
9 import java.util.stream.Collectors;
10 import java.util.stream.Stream;
11 
12 import static java.util.function.Function.identity;
13 
14 public class WordCountService {
15 
16     private final Map<String, Long> wordCount;
17     private final List<WordCountVO> topWords;
18 
19     public WordCountService(Stream<String> lines) {
20         wordCount = lines.flatMap(s -> Arrays.stream(s.split("\\W+")))
21                 .collect(
22                         Collectors.groupingBy(
23                                 String::toLowerCase,
24                                 Collectors.counting()
25                         )
26                 );
27 
28         topWords = wordCount.entrySet().stream().
29                 sorted(Map.Entry.<String, Long>comparingByValue().reversed()).
30                 map(e -> WordCountVO.builder().
31                         word(e.getKey()).
32                         count(e.getValue()).
33                         build()).
34                 collect(Collectors.toList());
35     }
36 
37     public Map<String, Long> getWordCount(List<String> words) {
38         return words.stream().
39                 collect(
40                         Collectors.toMap(
41                                 identity(),
42                                 w -> wordCount.getOrDefault(w.toLowerCase(), 0L),
43                                 (u, v) -> v, //ignore duplicate values
44                                 LinkedHashMap::new //preserve order of keys
45                         )
46                 );
47     }
48 
49     public Stream<WordCountVO> topWords(int n) {
50         return topWords.stream().
51                 limit(n);
52     }
53 }