如何将此 CSV 文件的内容存储到对象数组中

Question

我正在尝试制作一个 Java 程序，其中电视节目数据的 CSV 文件的内容存储在 TVShow 对象数组中。我让 TVShow 类对每个 CSV 文件的类别都有一个变量。

当我尝试跑步时，我不断收到NoSuchElementException。我尝试打印出文件的内容，它可以工作，但我不知道程序出了什么问题。

编辑： 根据@gthanop 的建议，我更改了下面的 Main.java 代码。现在的问题是数组的所有元素都是 CSV 文件的第一行。

这是 CSV 文件，然后是我的代码：

public class TVShow
{
  String name;
  String yearPremiered;
  String numOfSeasons;
  String numOfEpisodes;
  String network;
  String genre;
  String maleLead;
  String femaleLead;

  public TVShow(String name, String yearPremiered, String numOfSeasons, String numOfEpisodes, String network, String genre, String maleLead, String femaleLead)
  {
    this.name = name;
    this.yearPremiered = yearPremiered;
    this.numOfSeasons = numOfSeasons;
    this.numOfEpisodes = numOfEpisodes;
    this.network = network;
    this.genre = genre;
    this.maleLead = maleLead;
    this.femaleLead = femaleLead;
  } 
}

import java.io.*;
import java.util.Scanner;

public class Main
{
  public static void main(String[] args) throws Exception
  {
    TVShow[] array = new TVShow[20]; //There are 20 rows of TV show data in the CSV file

    Scanner read = new Scanner(new File("tv_shows.csv"));

    read.nextLine();

    int row = 0;

    read.useDelimiter(",|\n");

    while (read.hasNext())
    {
      String name = read.next();
      String yearPremiered = read.next();
      String numOfSeasons = read.next();
      String numOfEpisodes = read.next();
      String network = read.next();
      String genre = read.next();
      String maleLead = read.next();
      String femaleLead = read.next();

      while (row < 20)
      {
        array[row] = new TVShow(name, yearPremiered, numOfSeasons, numOfEpisodes, network, genre, maleLead, femaleLead);
        row++;
      }
    }

    read.close();

    for (int i = 0; i < 20; i++)
    {
      System.out.println(array[i]);
    }
  }
}

Answer 1

只需使用",|\n" 作为分隔符，因为行分隔符也用于分隔值。

例如：

public class Main {
    private static class TVShow {
        private final String name;
        private final int number;

        public TVShow(final String name,
                      final int number) {
            this.name = name;
            this.number = number;
        }

        @Override
        public String toString() {
            return "{name = " + name + ", number = " + number + '}';
        }
    }

    public static void main(final String[] args) {
        final ArrayList<TVShow> shows = new ArrayList<>();
        try (final Scanner scan = new Scanner("a,0\nb,1\nc,2")) {
            scan.useDelimiter(",|\n");
            while (scan.hasNext()) {
                final String name = scan.next();
                final int number = scan.nextInt();
                shows.add(new TVShow(name, number));
            }
        }
        System.out.println(shows);
    }
}

注意：您确定作为构造参数调用的read2.next() 以所需的顺序执行吗？因为很久以前发生在我身上（我不记得使用哪种语言，很可能是 C++），序列与预期的完全相反......所以请确保按顺序读取 CSV 值（ ie read-then-assign-to-variable) 然后构造你的TVShow 对象。就像上面的例子一样，我没有打电话：

shows.add(new TVShow(scan.next(), scan.nextInt()));

而是：

final String name = scan.next();
final int number = scan.nextInt();
shows.add(new TVShow(name, number));

更新 1：

在您更新后的代码中，您就快到了。只需像这样删除内部循环：

import java.io.*;
import java.util.Scanner;

public class Main
{
  public static void main(String[] args) throws Exception
  {
    TVShow[] array = new TVShow[20]; //There are 20 rows of TV show data in the CSV file

    Scanner read = new Scanner(new File("tv_shows.csv"));

    read.nextLine();

    int row = 0;

    read.useDelimiter(",|\n");

    while (read.hasNext())
    {
      String name = read.next();
      String yearPremiered = read.next();
      String numOfSeasons = read.next();
      String numOfEpisodes = read.next();
      String network = read.next();
      String genre = read.next();
      String maleLead = read.next();
      String femaleLead = read.next();

      array[row] = new TVShow(name, yearPremiered, numOfSeasons, numOfEpisodes, network, genre, maleLead, femaleLead);
      row++;
    }

    read.close();

    for (int i = 0; i < 20; i++)
    {
      System.out.println(array[i]);
    }
  }
}

---

不过，在我看来，您可以从 Apache Commons CSV 或类似的库中获得更可靠的结果。