过多的迭代使数据结构混乱答案

【问题标题】：superabundance of iterations cluttering data structures过多的迭代使数据结构混乱
【发布时间】：2015-02-17 05:59:56
【问题描述】：

我希望我的输出如下所示：

/home/flavius/data/train/politics/p_0.txt, [L'Etat,, c'est, moi.]
/home/flavius/data/train/science/s_0.txt, [If, I, have, seen, further, it, is, by, standing, on, the, shoulders, of, giants.]
/home/flavius/data/train/atheism/a_0.txt, [Gott, ist, tot.]
/home/flavius/data/train/sports/s_1.txt, [You, miss, 100%, of, the, shots, you, don't, take.]

但在这个关头，它看起来像下面这样，前面附加了四行：

/home/flavius/data/train/atheism/a_0.txt
/home/flavius/data/train/politics/p_0.txt
/home/flavius/data/train/science/s_0.txt
/home/flavius/data/train/sports/s_1.txt
/home/flavius/data/train/politics/p_0.txt, [L'Etat,, c'est, moi.]
/home/flavius/data/train/science/s_0.txt, [If, I, have, seen, further, it, is, by, standing, on, the, shoulders, of, giants.]
/home/flavius/data/train/atheism/a_0.txt, [Gott, ist, tot.]
/home/flavius/data/train/sports/s_1.txt, [You, miss, 100%, of, the, shots, you, don't, take.]

我的问题是，为什么要添加前四行？

程序读取四个目录下的不同文件，然后为每个文件在哈希图中创建一个条目，其中文件名作为键，该文件中包含的所有单词存储为数组列表。

这是代码，非常简单。也许有人可以发现我哪里出错了。

public class FileDictCreateur 
{
    static String PATH = "/home/flavius/data/train";

    static Map<File, ArrayList<String> > fileDict = new HashMap<>();

    public static void main(String[] args) throws IOException 
    {
        //each of the diferent categories
        String[] categories = { "/atheism", "/politics", "/science", "/sports"};

        //cycle through all categories once to populate the global dict
        for(int cycle = 0; cycle <= 3; cycle++)
        {
            String general_data_partition = PATH + categories[cycle];

            File directory = new File( general_data_partition );
            iterateDirectory( directory );  
        }

        for (Map.Entry entry : fileDict.entrySet()) 
        {
            System.out.println(entry.getKey() + ", " + entry.getValue());
        }
    }

    private static void iterateDirectory(File directory) throws IOException 
    {
        for (File file : directory.listFiles()) 
        {
            if (file.isDirectory()) 
            {
                iterateDirectory(directory);
            } 
            else 
            {
                System.out.println(file);

                String line; 
                BufferedReader br = new BufferedReader(new FileReader( file ));

                while ((line = br.readLine()) != null) 
                {
                    String[] words = line.split(" ");//those are your words

                    //populate_globo_dict(words);

                    create_file_dict( file, words );

                }
            }
        }
    }

    public static void create_file_dict( File file, String[] words ) throws IOException
    {   

        if (!fileDict.containsKey(file))
        {
            ArrayList document_words = new ArrayList<String>();

            String word;

            for (int i = 0; i < words.length; i++) 
            {
                word = words[i];

                document_words.add(word);
            }
            fileDict.put(file, document_words);
        }
    }
}

【问题讨论】：

标签： java arraylist io

【解决方案1】：

从此for循环：

for (int cycle = 0; cycle <= 3; cycle++) {
        String general_data_partition = PATH + categories[cycle];
        File directory = new File(general_data_partition);
        System.out.println(directory);
        iterateDirectory(directory);
 }

删除以下语句：System.out.println(directory); 打印目录名称。

【讨论】：

【解决方案2】：

是的，在iterateDirectory() 内的else 中有System.out.println(file)。

这意味着每次你到达一个文件而不是一个目录时，它的名字都会被打印出来。

【讨论】：