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在Java中传递2D数组列表

有人能告诉我如何为这个2D ArrayList设置getter和setter吗

public class PureRatings {
private List<List<Integer>> pureRatingsList;

我不确定这部分是否正确

public PureRatings() throws IOException {
    pureRatingsList = parseRatingsFile();
}

这是2D ArrayList其余部分的代码,我不知道是否应该包含它

public static List<List<Integer>> parseRatingsFile() throws IOException {
    List<List<Integer>> pureRatings = new ArrayList<List<Integer>>();

    BufferedReader in = new BufferedReader(new FileReader("Ratings.txt"));
    String ratingsLine = null;
    while ((ratingsLine = in.readLine()) != null) {
        pureRatings.add(parseRatingsLine(ratingsLine));
    }
    in.close();

    return pureRatings;
}

public static List<Integer> parseRatingsLine(String ratingsLine) throws IOException {
    List<Integer> ratings = new ArrayList<Integer>();
    if (ratingsLine == null) {
        return ratings;
    }

    String[] ratingsStrArr = ratingsLine.split(" ");
    try {
        for (final String ratingStr : ratingsStrArr) {
            ratings.add(Integer.parseInt(ratingStr));

        }
    } catch (NumberFormatException e) {
        System.out.println(e.getMessage());
    }

    return ratings;
}

}


共 (2) 个答案

  1. # 1 楼答案

    您将获得如下条目:

    pureRatingsList.get(line).get(column);
    

    您可以这样设置一个条目:

    pureRatings.get(line).set(column, newValue);
    
  2. # 2 楼答案

    public void setPureRatingsList(List<List<Integer>> lst)
    {
      pureRatingsList = lst;
    }
    
    public List<List<Integer>> getPureRatingsList()
    {
      return Collections.unmodifiableList(pureRatingsList);
    }