Question

嘿大家我正在做一个项目并且遇到一点麻烦我收到了java.util.InputMismatchException任何帮助都会非常感激。我真的很喜欢用java编程，所以请原谅我，如果我犯了一个明显的愚蠢错误。该程序的目的是读取一个文件获取前三行用于6个不同的变量（三个整数和三个字符串）然后读取文件的其余部分，格式化，然后做一些数学然后把它放到一个新的文件。我从中获取数据的文件格式如下。

法院50

专栏10

Club 25

Rascal Conway 10 Box

Loretta Barrett 3 Court

Loras Tyrell 5俱乐部

Margaery Tyrell 8 Box。

以下是代码：

public class ProjectTicket {
    public static void main(String[] args) throws IOException {

        /////////////////////// amount of tickets person would buy 
        int amount;
        /////////////////////// the tickets prices
        int tprice1 = 0;
        int tprice2 = 0;
        int tprice3 = 0;
        //////////////////////the ticket types
        String ticket1 = null;
        String ticket2 = null;
        String ticket3 = null;

        ////////////////////// the total price
        int price = 0;
        ////////////////////// customers name 
        String firstName;
        String lastName;
        ////////////////////// name of seat type
        String seat;


        PrintWriter outputFile = new PrintWriter("portland2out.txt");
        File file = new File("portlandvip2.txt");
        Scanner inputFile = new Scanner(file);

        ////////////////////// getting ticket name and ticket price

        for (int i = 0; i < 2; i++) {
            ticket1 = inputFile.next();
            tprice1 = inputFile.nextInt();
            ticket2 = inputFile.next();
            tprice2 = inputFile.nextInt();
            ticket3 = inputFile.next();
            tprice3 = inputFile.nextInt();
            outputFile.println(ticket1 + " " + "$" + tprice1);
            outputFile.println(ticket2 + " " + "$" + tprice2);
            outputFile.println(ticket3 + " " + "$" + tprice3);

        }

        ////////////////////// getting customer name,number of tickets, type of ticket
        while (inputFile.hasNext()) {
            firstName = inputFile.next();
            lastName = inputFile.next();
            amount = inputFile.nextInt();
            seat = inputFile.next();
            ////////////////////////////////// doing math for final billing.  
            if (seat.equals(ticket1))
                price = tprice1 * amount;
            else if (seat.equals(ticket2))
                price = tprice2 * amount;
            else if (seat.equals(ticket3))
                price = tprice3 * amount;
            ///////////////////////////////// printing in format to file

            outputFile.printf("%-10s%-10s$%,.2f\n", firstName, lastName, price);


        }
        inputFile.close();
    }
}

这是错误：

java.util.InputMismatchException
at java.util.Scanner.throwFor(Unknown Source)
at java.util.Scanner.next(Unknown Source)
at java.util.Scanner.nextInt(Unknown Source)
at java.util.Scanner.nextInt(Unknown Source)
at BlancovichProject2.main(BlancovichProject2.java:42)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at      edu.rice.cs.drjava.model.compiler.JavacCompiler.runCommand(JavacCompiler.java:272)

我不确定问题是什么。我一直在环顾四周，当检索到的信息不是它正在寻找的时候，似乎给出了错误类型。再次感谢您的任何帮助！

Answer 1

您正在尝试使用

ticket1 = inputFile.next();
tprice1 = inputFile.nextInt();

对于看起来像Rascal Conway 10 Box的数据，因此您尝试将Conway读为引发InputMismatchException的整数。

Answer 2

它可以工作，但你只需要迭代一次或取消forloop

更改：

for (int i = 0; i < 2; i++) { ticket1 = inputFile.next(); tprice1 = inputFile.nextInt(); ticket2 = inputFile.next(); tprice2 = inputFile.nextInt(); ticket3 = inputFile.next(); tprice3 = inputFile.nextInt(); outputFile.println(ticket1 + " " + "$" + tprice1); outputFile.println(ticket2 + " " + "$" + tprice2); outputFile.println(ticket3 + " " + "$" + tprice3); }

到此：

ticket1 = inputFile.next(); tprice1 = inputFile.nextInt(); ticket2 = inputFile.next(); tprice2 = inputFile.nextInt(); ticket3 = inputFile.next(); tprice3 = inputFile.nextInt(); outputFile.println(ticket1 + " " + "$" + tprice1); outputFile.println(ticket2 + " " + "$" + tprice2); outputFile.println(ticket3 + " " + "$" + tprice3);

此外，您对printf的格式错误。要验证结果注释

//outputFile.printf("%-10s%-10s$%,.2f\n", firstName, lastName, price);

并添加此项以验证您是否具有正确的输出：

System.out.printf("%-10s%-10s$%,d\n", firstName, lastName, price);

然后如果他们是对的......你可以将它输出到你的文件..

java.util.InputMismatchException错误

2 个答案: