在文本中进行Java搜索，并在文本周围返回多行

String filePath = "path/to/text/file.txt";
try {
    FileReader fileReader = new FileReader(filePath);
    BufferedReader bufferedReader = new BufferedReader(fileReader);
    String line;
    while ((line = bufferedReader.readLine()) != null) {
        // 在这里进行搜索操作
    }
    bufferedReader.close();
} catch (IOException e) {
    e.printStackTrace();
}

String keyword = "Java";
int numLines = 3; // 返回匹配行的前后各3行

try {
    FileReader fileReader = new FileReader(filePath);
    BufferedReader bufferedReader = new BufferedReader(fileReader);
    String line;
    List<String> matchedLines = new ArrayList<>();
    while ((line = bufferedReader.readLine()) != null) {
        if (line.matches(".*" + keyword + ".*")) {
            matchedLines.add(line);
            for (int i = 1; i <= numLines; i++) {
                if ((line = bufferedReader.readLine()) != null) {
                    matchedLines.add(line);
                }
            }
            break; // 找到匹配行后停止搜索
        }
    }
    bufferedReader.close();
    
    // 打印匹配行的结果
    for (String matchedLine : matchedLines) {
        System.out.println(matchedLine);
    }
} catch (IOException e) {
    e.printStackTrace();
}