挂起的未捕获异常线程[main]（挂起（未捕获异常输入不匹配异常））

Question

我只是在练习java，目前我正在试验getter/setter方法和构造函数。java程序的工作原理是，我能够将用户输入存储到对象中，但当我将字符串“Dice and rollers”输入到gametype字符串变量中时，会出现一个挂起的未捕获异常InputMismatch错误。

有人能给我解释一下这是为什么吗？

另外，我在下面分享了我的源代码。

    package test;

import java.util.Scanner;

public class Test8a {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        
        System.out.println("Please enter the following information: Boardgame name, Alternative Name, Game Type, Year Released, Price and Maximum amount of Players");
        String name = in.next();
        String secondaryname = in.next();
        String type = in.next();
        int date = in.nextInt();
        double price = in.nextDouble();
        int player = in.nextInt();
        System.out.println();
        
        new Test8b(name, secondaryname, type, date, price, player);
    }
}

上面的是超类，下面的源代码是构造函数和getter/setter java文件。

package test;

public class Test8b {
    private String boardname;
    private String secondaryname;
    private String gametype;
    private int date;
    private double price;
    private int numberofPlayers;
    
    public Test8b(String boardname, String secondaryname, String gametype, int date, double price, int players) {
        setBoardname(boardname);
        setSecondaryname(secondaryname);
        setGametype(gametype);
        setDate(date);
        setPrice(price);
        setNumberofPlayers(players);
        
        this.printDetails();
    }

    public String getBoardname() {
        return boardname;
    }
    
    public String getSecondaryname() {
        return secondaryname;
    }

    public String getGametype() {
        return gametype;
    }

    public int getDate() {
        return date;
    }

    public double getPrice() {
        return price;
    }
    
    public int getNumberofPlayers() {
        return numberofPlayers;
    }

    public void setBoardname(String boardname) {
        if (boardname.length() >= 15) {
            System.out.println("There is no boardgame with this name length! Please enter a valid name!");
        } else this.boardname = boardname;
    }
    
    public void setSecondaryname (String secondaryname) {
        if (secondaryname.length() >= 15) {
            System.out.println("There is no boardgame with this name length! Please enter a valid name!");
        } else this.secondaryname = secondaryname;
    }

    public void setGametype(String gametype) {
        this.gametype = gametype;
    }

    public void setDate(int date) {
        if (date > 2021) {
            System.out.println("This game haven't been invented yet or are you a time traveller?");
        } else this.date = date;
    }

    public void setPrice(double price) {
        if (price <= 0) {
            System.out.println("Can't give away free games!");
        } else this.price = price;
    }

    public void setNumberofPlayers(int numberofPlayers) {
        if (numberofPlayers <= 0) {
            System.out.println("Need someone to play the game!");
        } else this.numberofPlayers = numberofPlayers;
    }
    
    public void printDetails() {
        System.out.print(
                "Board Game: " + this.getBoardname() + "\n" +
                "Alternative Title: " + this.getSecondaryname() + "\n" +
                "Game Type: " + this.getGametype() + "\n" +
                "Year Released: " + this.getDate() + "\n" +
                "Price: " + this.getPrice() + "\n" +
                "Maximum # of Players: " + this.getNumberofPlayers() + "\n"
                );
    }
}

Answer 1

Scanner对象的next（）方法引发异常，因为在输入带空格的字符串时输入的内容与用于扫描的扫描仪的默认分隔符模式不匹配。当您输入带空格的字符串时，扫描仪会看到一行字符，而不仅仅是一个输入字。换句话说，它区分单个单词和由空格分隔的一行单词。

java。util。扫描仪。nextLine（）方法使扫描器前进超过当前行，并返回跳过的输入，这是您应该用来扫描游戏类型的方法。修改代码以使用扫描仪。nextLine（）用于游戏类型和可能包含多个单词的任何其他类型。