java - 我在将文本读入数组时遇到问题，我需要在此代码中更改什么？

Question

这是我当前正在尝试读取的文本文件:

Buffalo
Montreal
Boston
Ottawa
Toronto

每当我运行此代码时，数组的 5 个元素都会打印为“null”，因此不知何故我没有将信息正确存储到数组中。这是我到目前为止的代码! (我正在使用 Ready To Program IDE)

// The "Hockey" class.
import java.awt.*;
import hsa.Console;
import java.io.*;

public class Hockey
{
    static Console c;           // The output console

    public static void main (String[] args) throws IOException
    {
        c = new Console ();

        //setting up file reading
        FileReader fr = new FileReader ("cities.txt");
        BufferedReader br = new BufferedReader (fr);

        //initialising array
        String cities[] = new String [5];

        //loop to read in the 5 entries
        for (int i = 0 ; i > cities.length ; i++)
        {
            cities [i] = br.readLine ();
        }

        //loop to print all elements of "cities" to the console
        for (int i = 0 ; i < cities.length ; i++)
        {
            c.println (cities [i]);
        }
            // Place your program here.  'c' is the output console
    } // main method

} // Hockey class

感谢您的帮助!

Answer 1

您的 for 循环条件不正确。

//loop to read in the 5 entries
for (int i = 0 ; i > cities.length ; i++) //reads as (i greater than cities.length)
{                ^^^^^^^^^^^^^^^^^
    cities [i] = br.readLine ();
}

上面应该是:i < cities.length; (i 小于城市.长度)

循环没有运行，这解释了为什么你的数组没有填充。