java - 从文本中找出一个单词的所有行号

Question

我写了一个方法，它必须找到word的所有行号，然后打印它们。
输入必须在后面

 Word:works/*(just one in file)*/Line Number:[7]  
 Word:run                      Line Number:[3,7,9]
 Word:we                       Line Number[5,8]   

这就是我的方法

HashMap m2 = new HashMap();

public void addLine(FileReader file) throws IOException {
        try {
            LineNumberReader lnR = new LineNumberReader(file);
            StringBuilder sb = new StringBuilder();
            String line = lnR.readLine();

            while (line != null) {
                String[] words = line.split("\\W+");
                for (int i = 0; i < words.length; i++) {
                    if (m2.get(words[i].toLowerCase()) == null) {
                        m2.put(words[i].toLowerCase(), "[" + lnR.getLineNumber() + " ");
                    } else {
                        int x = lnR.getLineNumber();
                        m2.put(words[i].toLowerCase(), " " + x + "]");
                    }
                }
                sb.append(System.lineSeparator());
                line = lnR.readLine();
            }
            lnR.close();
        } catch (IOException ex) {
            System.out.println("Error reading file '" + file + "'");
        }
    }

还有我的主要方法。

public static void main(String[] args) throws IOException {
addLine(new FileReader("C:/Users/Text.txt"));
Map<String, String> sorted1 = new TreeMap<String, String>(m2);
        for (Object key : sorted1.keySet()) {
            System.out.println("Word: " + key + "\tLine Number: " m2.get(key));
        }
}

我的方法给出了错误的输出。

Word: write     Line Number:  [9
Word: we    Line Number:  8]

我该如何解决这个问题？
感谢所有读者。

Answer 1

试试这个。

static Map<String, List<Integer>> addLine(Reader reader) {
    LineNumberReader r = new LineNumberReader(reader);
    return r.lines()
        .filter(line -> line.length() != 0)
        .flatMap(line -> Arrays.stream(line.split("\\W+")))
        .map(word -> word.toLowerCase())
        .collect(Collectors.groupingBy(word -> word,
            TreeMap::new,
            Collectors.mapping(word -> r.getLineNumber(), Collectors.toList())));
}

public static void main(String[] args) throws IOException {
    try (Reader reader = new FileReader("C:/Users/Text.txt")) {
        for (Entry<String, List<Integer>> e : addLine(reader).entrySet())
            System.out.println("Word: " + e.getKey() + "\tLine Number: " + e.getValue());
    }
}