Question

我试图避免使用两个文件，而只是将它们组合成一个文件。

所以我在.java文件中创建了一个类，它的外观如下：

import javax.swing.JOptionPane;

public class Raindrop {

    double [] rainfallStats;

    public double getTotalRainfall() {
        double totalRainfall;

        for ( int index = 0; index < rainfallStats.length; index++) {
            totalRainfall = totalRainfall + rainfallStats[ index ];
        }
        return totalRainfall;
    }

    public double getAverageRainfall() {
        return getTotalRainfall() / rainfallStats.length;
    }

    public double getMostRainMonth () {
        double mostRain = rainfallStats [ 0 ];
        int mostRainMonth;

        for( int index = 0; index < rainfallStats.length; index++ ) {
            if ( rainfallStats[ index ] > mostRain ) {
                mostRain = rainfallStats [ index ];
                mostRainMonth = index + 1;
            }
        }
        return mostRainMonth;
    }

    public double getLeastRainMonth () {
       double leastRain = rainfallStats [ 0 ];
       int leastRainMonth;

       for( int index = 0; index < rainfallStats.length; index++ ) {
           if ( rainfallStats[ index ] > leastRain ) {
               leastRain = rainfallStats [ index ];
               leastRainMonth = index + 1;
           }
       }
       return leastRainMonth;
    }

    public Rainfall ( double [] rainfallStatsGiven) {
        rainfallStats = new double [ rainfallStatsGiven.length ];
        for (int index = 0; index < rainfallStatsGiven; index++) {
            rainfallStats[ index ] = rainfallStatsGiven [ index ];
        }
    }


    public static void fillArrayWithUserInput ( double [] arrayGiven ) {
        String userInputString;
        double userMonthlyRainfallFigure;

        for ( int index = 0; index < arrayGiven.length; index++ ){
            userInputString = JOptionPane.showInputDialog(
                    "Please enter rainfall figures for month " + (index + 1) );
            userMonthlyRainfallFigure = Double.parseDouble( userInputString );
            arrayGiven [ index ] = userMonthlyRainfallFigure;
        }
    }

    public static void main(String[] args) {

        final int MONTH_IN_A_YEAR = 12;
        double [] rainfallStats = new double [12];
        String userOutputString;

        fillArrayWithUserInput( rainfallStats );

        Rainfall rainfallData = new Rainfall( rainfallStats );

        userOutputString = String.format ( 
                "Total rainfall: %f\nAverage monthly rainfall" + ":" 
                        + "%f\nMonth with most rain: %f\nMonth with least rain: %f", 
                                rainfallData.getTotalRainfall(),
                                rainfallData.getAverageRainfall(),
                                rainfallData.getMostRainMonth(),
                                rainfallData.getLeastRainMonth() );

        JOptionPane.showMessageDialog(null, userOutputString );

        System.exit( 0 );
    }

}

我收到错误：

Raindrop.java:45: error: invalid method declaration; return type required
public Rainfall ( double [] rainfallStatsGiven) {
       ^
1 error

我尝试将public Rainfall更改为一个方法，但它无法弄清楚如何做到这一点，想要了解如何使这项工作。我无法弄清楚如何嵌套类ethier，我无法弄清楚如何使公共类成为可行的其他任何东西。

Answer 1

我能够再次查看我的代码并发现许多错误并修复了它们，在此过程中，由于存在更多问题而修复了我的问题，因此我能够得到我想要的内容。如果有人也想看看，那么修改后的那个：

import javax.swing.JOptionPane;
 public class Rainfall {

   double [] rainfallStats;

   public double getTotalRainfall() {
       double totalRainfall =0;

       for ( int index = 0; index < rainfallStats.length; index++) {
       totalRainfall = totalRainfall + rainfallStats[ index ];
       }
       return totalRainfall;
   }

    public double getAverageRainfall() {
      return getTotalRainfall() / rainfallStats.length;
   }

   public double getMostRainMonth () {
       double mostRain = rainfallStats [ 0 ];
       int mostRainMonth = 1;

       for( int index = 0; index < rainfallStats.length; index++ ) {
           if ( rainfallStats[ index ] > mostRain ) {
               mostRain = rainfallStats [ index ];
               mostRainMonth = index + 1;
           }
       }
       return mostRainMonth;
  }

  public double getLeastRainMonth () {
       double leastRain = rainfallStats [ 0 ];
       int leastRainMonth =1;

       for( int index = 0; index < rainfallStats.length; index++ ) {
           if ( rainfallStats[ index ] < leastRain ) {
               leastRain = rainfallStats [ index ];
               leastRainMonth = index + 1;
           }
       }
       return leastRainMonth;
  }

    public Rainfall ( double [] rainfallStatsGiven) {
       rainfallStats = new double [ rainfallStatsGiven.length ];
    for (int index = 0; index < rainfallStatsGiven.length; index++) {
       rainfallStats[ index ] = rainfallStatsGiven [ index ];
       }
}


public static void fillArrayWithUserInput ( double [] arrayGiven ) {
    String userInputString;
    double userMonthlyRainfallFigure;

    for ( int index = 0; index < arrayGiven.length; index++ ){
    userInputString = JOptionPane.showInputDialog("Please enter rainfall figures for month " + (index + 1) );
    userMonthlyRainfallFigure = Double.parseDouble( userInputString );
    arrayGiven [ index ] = userMonthlyRainfallFigure;
    }
}

public static void main(String[] args) {

    final int MONTH_IN_A_YEAR = 12;
    double [] rainfallStats = new double [12];
    String userOutputString;

    fillArrayWithUserInput( rainfallStats );

    Rainfall rainfallData = new Rainfall( rainfallStats );

    userOutputString = String.format ( "Total rainfall: %f\nAverage monthly rainfall"+
                                        ":+ %f\nMonth with most rain: %f\nMonth with least rain: %f",
                                    rainfallData.getTotalRainfall(),
                                    rainfallData.getAverageRainfall(),
                                    rainfallData.getMostRainMonth(),
                                    rainfallData.getLeastRainMonth() );

    JOptionPane.showMessageDialog(null, userOutputString );

    System.exit( 0 );
        }

}

尝试将类文件合并到一个单独的java文件中

1 个答案: