java - 从 csv 文件读取数据 - 未找到有效源的文件异常

Question

我在从网络读取 csv 文件时遇到问题。我收到文件未找到异常。这就是来源:http://data.okfn.org/data/core/s-and-p-500-companies/r/constituents.csv明明可以轻松打开的文件，怎么会找不到呢？我在这里缺少什么？

package Investing;


import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

public class Main {

   public static void main(String[] args) {

    String csvFile = "http://data.okfn.org/data/core/s-and-p-500-     companies/r/constituents.csv";
    String line = "";
    String cvsSplitBy = ",";


    try (BufferedReader br = new BufferedReader(new FileReader(csvFile))) {

        while ((line = br.readLine()) != null) {

            // use comma as separator
            String[] data = line.split(cvsSplitBy);

            System.out.println(data);

        }

    } catch (IOException e) {
        e.printStackTrace();
    }


}
}

Answer 1

FileReader 用于本地文件。请参阅:Read remote .csv file using opencsv用于读取远程 cvs 文件。

另一种读取远程文件的方法:

public static void main(String[] args) {

    String csvFile = "http://data.okfn.org/data/core/s-and-p-500-companies/r/constituents.csv";

    try {
        URL url12 = new URL(csvFile);
        URLConnection urlConn = url12.openConnection();
        InputStreamReader inStream = new InputStreamReader(urlConn.getInputStream());
        BufferedReader buff = new BufferedReader(inStream);

        String line = buff.readLine();
        line  = buff.readLine();
        while (line != null) {

            System.out.println(line);
            line = buff.readLine();
        }
    } catch (Exception e) {
        e.printStackTrace();
    }

}