java - 如何从文本文件中读取我的输出？

Question

这个问题已经有答案了:

Java says FileNotFoundException but file exists (12 个回答)

已关闭 3 年前。

我遇到错误

java.io.FileNotFoundException: C:\courses2.txt (The system cannot find the file specified)

检查了 C 驱动器，路径是正确的，但由于某种原因我没有得到输出。

我得到的最多的是返回的教师副本，但无法读取文件。

我的输出应显示类(class)代码、类(class)学分和类(class)标题

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;

public class courses

{

    public static void main(String[] args) throws Exception

    {

        try {

            File file = new File("C:\\courses2.txt");

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

            String courseCode = "";

            String creditHours = "";

            String courseTitle = "";

            String st;

            System.out.println("Teacher's Copy");

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

                courseCode = st.substring(0, st.indexOf(" "));

                creditHours = st.substring(6, 8);

                courseTitle = st.substring(9);

                System.out.print("Course code = " + courseCode + " | ");

                System.out.print("Course credit hours = " + creditHours + " | ");

                System.out.print("Course Title = " + courseTitle);

                System.out.println();

            }

        } catch (Exception ex) {

            System.out.println(ex);

        }

    }

}

Answer 1

首先，编写一段简单的代码来检查特定文件是否存在。

代码:

public class Test {

   public static void main(String...args) {
       File file = new File("C:\\courses2.txt");
       if(file.exists()) {
           System.out.println("File exists");
       } else {
           System.out.println("File doesn't exist");
       }

   }

} 

如果文件不存在，则检查该路径是否缺少该文件或文件名不匹配。