java - 导出具有多个值的变量？

import java.util.*;
import java.text.*;
import java.io.*;

public class AvgTime {

static double hrs1;
static double min1;

public static void main(String[] args) throws InterruptedException, FileNotFoundException {

Scanner in = new Scanner(System.in);

System.out.print("How many times? ");
int numOfTimes = in.nextInt();

double hrTotal = 0;
double minTotal = 0;

for (int i = 1; i <= numOfTimes; i++){

  System.out.println("\nEnter time in military time notation: ");
  System.out.print("Hour  ");
  double hrs1 = in.nextDouble();
  System.out.print("Minute  ");
  double min1 = in.nextDouble();



  hrTotal += hrs1;
  minTotal += min1;
}

//calculate average
double avgHr1 = hrTotal/numOfTimes;
double timeMin1 = Math.round(minTotal/numOfTimes);


DecimalFormat df = new DecimalFormat("###");
String hours = df.format(avgHr1);
String minutes = df.format(timeMin1);

String time = hours+":"+minutes+":"+00;
String mt = hours+minutes;


    SimpleDateFormat fmtMil = new SimpleDateFormat("HH:mm:ss");
    Date inDate = fmtMil.parse(time, new ParsePosition(0));
    SimpleDateFormat fmtAMPM = new SimpleDateFormat("hh:mm:ss aa");
    StringBuffer outDate = fmtAMPM.format(inDate, new StringBuffer(), new FieldPosition(0));
System.out.println("\nThe average time is " + outDate+"\n"+mt+" in military time.\n\n");

    String copy = "Copying...";

    Thread.sleep( 550 );
    for( int i = 0; i < copy.length(); i++ ) {
        System.out.print(copy.charAt( i ) );
         try{ Thread.sleep( 105 ); }catch( Exception e ){}
        }


        PrintWriter p = new PrintWriter("Times.txt");
           p.println(hrs1+min1);
            p.close();


        System.out.println("\nDone\n\n\n");
            Thread.sleep( 550 );
  }
}

我希望它将用户输入的时间导出到文件中。例如，如果用户将numOfTimes设置为2，则hrs1和min1会有2个不同的值。

假设他们输入：1629和2018。

我希望文本文件像1629一样显示hrs1（16）和min1（29）。但是当我放入hrs1 + min1时，它不会输出'hrs1 + min1'，而只是输出'0.0'。我只希望它导出“ 1629”和“ 2018”
。

为什么会这样，我该如何解决？

输出量

How many times? 2

Enter time in military time notation:
Hour  16
Minute  29

Enter time in military time notation:
Hour  20
Minute  18

应该出口什么：

1629
2018

最佳答案

有两个主要的修改，以使此代码起作用。首先，必须在循环外部声明和实例化PrintWriter。并且对println的调用必须在循环内部进行。其次，在打印之前，必须将double转换为String并适当地子字符串化。

    Scanner in = new Scanner(System.in);

    System.out.print("How many times? ");
    int numOfTimes = in.nextInt();

    double hrTotal = 0;
    double minTotal = 0;

    PrintWriter p = new PrintWriter("Times.txt");

    for (int i = 1; i <= numOfTimes; i++) {

        System.out.println("\nEnter time in military time notation: ");
        System.out.print("Hour  ");
        double hrs1 = in.nextDouble();
        System.out.print("Minute  ");
        double min1 = in.nextDouble();

        hrTotal += hrs1;
        minTotal += min1;
        String hrs = String.valueOf(hrs1);
        String min = String.valueOf(min1);
        p.println(hrs.substring(0, hrs.indexOf(".")) + min.substring(0,min.indexOf(".")));
    }
    p.close();

在进行此更改之前，您的代码使用实际算术添加了两个双精度hrs1和mins1，并且使用了您在类顶部声明的静态变量。

static double hrs1;
static double min1;

您应该删除这些静态双打，因为它们实际上从未使用过。因为对println的调用在循环之外，所以导致引用了静态双精度值，而不是在循环内声明并分配了hrs1和mins1。您以为您使用的是在循环中声明的locals变量，但它们从未在范围内。