java - 如何找到以给定字母开头的单词

Question

给定字符串，例如:My name is James Bond iee我想在结果中有 Map以字符作为键，将字符串集作为值(这组字符串是以相应字符键开头的字符串)- Map<Character,Set<String>> .例如:

m - my, n - name, i - is, iee, j - james etc.

我完成了从标点符号中净化字符串和负责查找字符的编写方法。在我的示例中:(m,n,u,j,b)

这些方法:

static String getPurifiedSentenceFromPunctuationMarks(String sentence) {
    return sentence.replaceAll("\\p{P}", "");
}

static Set<Character> getEveryCharacterOccuringInSentence(String sentence) {
    return sentence.chars()
                .mapToObj(e -> (char) e).collect(Collectors.toSet());
}

现在，我想遍历每个字符和每个字符串以找到这些单词，但我正在为如何为每个字符创建集合而苦苦挣扎:

String purifiedSentenceFromPunctuationMarks = AP.getPurifiedSentenceFromPunctuationMarks(sentence);
        Set<Character> characters = AP.getEveryCharacterOccuringInSentence(purifiedSentenceFromPunctuationMarks);
        String[] words = purifiedSentenceFromPunctuationMarks.split("\\s");
        Map<Character, Set<String>> characterWithAccordingWord = new LinkedHashMap<>();
        Set<String> nonRepeatableWords = new HashSet<>();

        for (char iteratedCharacter : characters) {
            for (String iteratedWord : words) {
                if (iteratedWord.indexOf(iteratedCharacter) >= 0) {
                    characterWithAccordingWord.put(iteratedCharacter, )
                }
            }
        }

如您所见，我在需要添加字符串以设置 iteratedCharacter 的那一刻停止了.怎么做到的？也许与流一起更好？我最想在这里使用流。

Answer 1

使用流，一旦您拥有了 String[] words 中所有单词的数组，您可以将它们按第一个字符分组，然后收集成一个 设置为:

Map<Character, Set<String>> characterWithAccordingWord =
        Arrays.stream(words).collect(Collectors.groupingBy(word -> word.charAt(0), 
                Collectors.toSet()));