为什么在Java中以txt文件格式读取文件时出错

static String[][] parseCSV(String fileName) throws FileNotFoundException, IOException {
        int fields;
        int lines;    

        try (BufferedReader br = new BufferedReader(new FileReader("C:\\Users\\hp\\Documents\\Documents\\ID3ALGORITHM\\playtennis.txt"))) {
            String s = br.readLine();
            fields = 1;
            int index = 0;
            while ((index = s.indexOf(',', index) + 1) > 0)
                fields++;
            lines = 1;
            while (br.readLine() != null)
                lines++;
        }
    String[][] data = new String[lines][fields];
    Scanner sc = new Scanner(new File("C:\\Users\\hp\\Documents\\Documents\\ID3ALGORITHM\\playtennis2.txt"));
    sc.useDelimiter("[,\n]");
    for (int l = 0; l < lines; l++)
        for (int f = 0; f < fields; f++)
            if (sc.hasNext())
                data[l][f] = sc.next();
            else
                error("Scan error in " + "playtennis2.txt" + " at " + l + ":" + f);
    sc.close();
    return data;
} // parseCSV()

public static void main(String[] args) throws FileNotFoundException,IOException {
    if (args.length != 2)
        error("Expected 2 arguments: file names of training and test data");
    String[][] trainingData = parseCSV(args[0]);
    String[][] testData = parseCSV(args[1]);
    ID3ALGO classifier = new ID3ALGO();
    classifier.train(trainingData);
    classifier.printTree();
    classifier.classify(testData);

} // main()

收到的错误：预期2个参数：训练和测试数据的文件名。为什么会发生什么？ parseCSV的参数由同一文件夹中的两个不同文件组成，系统无法读取该文件。