java - 生成包含球员姓名、FGM、FGA 和投篮命中率(即 FGP)的输出报告

Question

我已经编译了代码，但出现了运行时错误:java.util.InputMismatchException:null(in.java.util.Scanner)

这是我的以下代码:

import java.io.*;
import java.util.Scanner;
public class kstatebball
{
    public static void main(String [] args)
    throws FileNotFoundException, IOException
    {
        Scanner inFile = new Scanner(new File("data1.txt"));
        int  count = 1;
        int fgm[] = new int [100];
        int fga[] = new int [100];
        double fgp = 0;
        int read,maxFGP,minFGP;

        read = readArray(fgm,fga,count,inFile);
        maxFGP = maxFGP(fgm,fga,count);
        minFGP = minFGP(fgm,fga,count);


        System.out.print("Player        FGM     FGA     FGP%\n");
        System.out.printf("%15d         %3d     %3d     %2.1f",count,fgm,fga,fgp);
        System.out.printf("The player with the highest fieldgoal percantage is: %3d",fgp);
        System.out.printf("The player with the lowest field goal percantage is : %3d",fgp);

        inFile.close();      
    }

    static int readArray(int [] fgm, int [] fga, int count, Scanner inFile)
    {
        double temp = inFile.nextDouble();
        int k;
        int v;
        v = inFile.nextInt();
        for(k = 0; (v!=-999) && (k<count); k++)
        {
            fgm[k] = v;
            v=inFile.nextInt();
        }
        return k;
    }

    public static int maxFGP(int[] fgm, int[] fga, int count)
    {
        for(int i = 0; i < 13; i++)
        {
            if(fgm[i] < fgm[count])
                count = i;            
        }
        return count;
    }

    public static int minFGP(int[]fgm, int[]fga, int count)
    {

        for(int i = 0; i > 13; i++)
        {
            if(fgm[i] > fgm[count])
                count = i;            
        }
        return count;
    }        
}

here is my data file I am reading in:
Marcus Foster    123    288
Thomas Gipson    102    178
Shane Southwell    88    224
Will Spradling    58    144
Wesley Iwundu    53    111
Nino Williams    49    96
Nigel Johnson    28    80
Jevon Thomas    15    58
D.J. Johnson    34    68
Omari Lawrence    27    65
Shawn Meyer 2    4
Ryan Schultz    2    9
Jack Karapetyan    1    4
Brian Rohleder    1    2
-999

我试图让我的输出如下所示:

    Marcus Foster    123    288        42%
    Thomas Gipson    102    178        57%
    Shane Southwell    88    224       39%      
    Will Spradling    58    144        40%
    Wesley Iwundu    53    111         47%
    Nino Williams    49    96          51%
    Nigel Johnson    28    80          35%
    Jevon Thomas    15    58           25%
    D.J. Johnson    34    68           50%
    Omari Lawrence    27    65         41%
    Shawn Meyer 2    4                 50%
    Ryan Schultz    2    9             22%
    Jack Karapetyan    1    4          25%
    Brian Rohleder    1    2           50%

投篮命中率最高的球员是托马斯·吉布森，投篮命中率为 57%。

投篮命中率最低的球员是 Ryan Schultz，为 22%

Answer 1

当您调用方法(如 nextDouble 或 nextInt())时，java.util.Scanner 类会抛出 java.util.InputMismatchException 错误，当读取的数据与您告诉它读取的类型不匹配时。请参阅http://docs.oracle.com/javase/7/docs/api/java/util/Scanner.html#nextDouble()

根据您的输入文件，您错误地尝试将字符串读取为 double 。

static int readArray(int [] fgm, int [] fga, int count, Scanner inFile)
{
    double temp = inFile.nextDouble();
    int k;
    int v;
    v = inFile.nextInt();
    for(k = 0; (v!=-999) && (k<count); k++)
    {
        fgm[k] = v;
        v=inFile.nextInt();
    }
    return k;
}