高中需要帮助请；是否将输出写入文件（使用“行驶距离”程序）？[闭门]

Question

有人能帮我完成下面的代码吗？我已经为此工作了几个小时，无论我做什么，似乎都无法将输出写入文件。我是一名高中生，向我的老师寻求帮助，但她寄给我的东西没有帮助，我现在完全不知所措。我自己独立学习这门课程，希望stackoverflow家族的人能给我一些建议？这不是因为我没有尝试。我只是不知所措。提前谢谢你！！

/**
 * 
 */
package distanceTraveledReport;
import java.util.Scanner;
import java.io.*;

/**
 * @author Jerin
 *
 */
public class DistanceTraveledReport {
    
    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        
        //prints out name and project I am working on
        System.out.println("Jerin Anderson, This is my Distance Traveled Report");
                
        //create scanner
        Scanner scanner = new Scanner(System.in);
        double vehicleSpeed = -1; //to hold the speed from the vehicle
        int hoursTraveled = 0; //to hold the hours traveled by the vehicle
        double distanceTraveled; //to hold the distance traveled for each hour
                
        //while loop, inputs validation
        while ( vehicleSpeed < 0 ) 
                {
                    System.out.println("Enter the speed of the vehicle (in miles-per-hour)" );
                    vehicleSpeed = scanner.nextDouble();
                }
        while (hoursTraveled < 1) 
                {
                    System.out.println("Enter the number of hours traveled by the vehicle" );
                    hoursTraveled = scanner.nextInt();
                }
                
        //heading at the top and lines to separate table
        System.out.println(" Hour\t Distance Traveled");
        System.out.println("---------------------------");
        
                {
        //write the table of distances
        distanceTraveled = 1;
        while (distanceTraveled <= hoursTraveled)
        {
            //Display the distance for this period.
            System.out.println(distanceTraveled + "\t\t" + distanceTraveled * vehicleSpeed);
            
            //Increment period
            distanceTraveled++;
        }
        
        //Close the file.
        System.out.close();
        System.out.println("Report written to DistanceReport.txt");
    }

}
    
}

Answer 1

您必须认识到System.out.println（）不会写入文件，但FileWriter会写入。代码的修复用//TODO突出显示。

package distanceTraveledReport;

import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;

/**
     * @author Jerin
     *
     */
    public class DistanceTraveledReport {

        /**
         * @param args
         */
        public static void main(String[] args) throws IOException {
            // TODO "TODO check this out" marks addition of FileWriter fileWriter.
            //TODO check this out
            //TODO make sure you change the filename

首先打开.txt文件的路径，因为当前路径不适用于您的文件（请参阅“cole.henrich/Downloads…”）。

然后复制绝对路径：

守则接着说：

FileWriter fileWriter = new FileWriter("/Users/cole.henrich/Downloads/StackOverFlow/src/distanceTraveledReport/DistanceReport.txt");
            fileWriter.write("The FileWriter writes to the file. System.out.println() does not.\n");

            //prints out name and project I am working on
            System.out.println("Jerin Anderson, This is my Distance Traveled Report");

            //create scanner
            Scanner scanner = new Scanner(System.in);
            double vehicleSpeed = -1; //to hold the speed from the vehicle
            int hoursTraveled = 0; //to hold the hours traveled by the vehicle
            double distanceTraveled; //to hold the distance traveled for each hour

            //while loop, inputs validation
            while ( vehicleSpeed < 0 )
            {
                System.out.println("Enter the speed of the vehicle (in miles-per-hour)" );
                vehicleSpeed = scanner.nextDouble();
            }
            while (hoursTraveled < 1)
            {
                System.out.println("Enter the number of hours traveled by the vehicle" );
                hoursTraveled = scanner.nextInt();
            }

            //heading at the top and lines to separate table
            System.out.println(" Hour\t Distance Traveled");
            System.out.println("---------------------------");

            {
                //write the table of distances
                distanceTraveled = 1;
                while (distanceTraveled <= hoursTraveled)
                {
                    //Display the distance for this period.
                    String display = ""+ (distanceTraveled + "\t\t" + distanceTraveled * vehicleSpeed) + "\n";
                    System.out.println(display);
                    //TODO check this out
                    fileWriter.write(display);
                    //Increment period
                    distanceTraveled++;
                }

                //Close the file.
                //TODO check this out
                fileWriter.close();
                //TODO check this out: DO NOT close the System.out. Close FileWriter fileWriter.
                System.out.println("Report written to DistanceReport.txt");
            }

        }

    }

确保你理解FileWriter。阅读评论中的链接。这是您的输出，在文件中（不是System.out）。

The FileWriter writes to the file. System.out.println() does not.
    1.0     65.0
    2.0     130.0
    3.0     195.0
    4.0     260.0
    5.0     325.0
    6.0     390.0
    7.0     455.0