Question

当我按下＆＃34; next＆＃34;时，我得到一个InputMismatchException。按钮。以下是具有按钮的面板的代码：

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class PanelSampleYard extends JPanel
{
    private JLabel label;
    private DisplaySampleYard display;
    int times = 0;
    public PanelSampleYard()
    {
        setLayout(new BorderLayout());
        setPreferredSize(new Dimension(200, 125));

        label = new JLabel("Green and Grow Mowing Company", SwingConstants.CENTER);
        add(label, BorderLayout.NORTH);

        display = new DisplaySampleYard();
        add(display, BorderLayout.CENTER);

        JPanel subpanel = new JPanel();
        subpanel.setLayout(new FlowLayout());
        JButton next = new JButton("Next");
        JButton quit = new JButton("Quit");
        next.addActionListener(new Listener1());
        quit.addActionListener(new Listener2());
        subpanel.add(next);
        subpanel.add(quit);
        add(subpanel, BorderLayout.SOUTH);
    }
    private class Listener1 implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {
            display.next(display.contents(times));
            times++;
        }
    }
    private class Listener2 implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {
            System.exit(0);
        }
    }
}

面板内显示的代码：

import javax.swing.*;
import java.awt.*;
import java.util.*; 
public class DisplaySampleYard extends JPanel
{
    private JLabel label;
    private JTextField last, first, size, cost, total;
    double sum = 0;
    int index = 0;
    public DisplaySampleYard()
    {
        setLayout(new GridLayout(5,2));
        last = new JTextField("");
        add(new JLabel("Last Name:"));
        add(last);
        first = new JTextField("");
        add(new JLabel("First Name:"));
        add(first);
        size = new JTextField("");
        add(new JLabel("Lawn Size:"));
        add(size);
        cost = new JTextField("");
        add(new JLabel("Total Cost:"));
        add(cost);
        total = new JTextField("");
        add(new JLabel("Running Total:"));
        add(total);
    }
    public void next(Customer c)
    {
        last.setText(c.getLastName()+"");
        first.setText(c.getFirstName()+"");
        size.setText(c.getSize()+"");
        cost.setText(c.getCost()+"");
        sum = sum + c.getCost();
        total.setText(""+sum);
    }
    public Customer contents(int index)
    {
        Scanner infile = new Scanner("greenGrow.txt");
        int reps = infile.nextInt();
        Customer[] array = new Customer[reps];
        for(int x = 0; x<reps; x++)
        {
            array[x].setLastName(infile.next());
            array[x].setFirstName(infile.next());
            array[x].setSize(infile.nextInt());
        }
        return array[index];
    }
}

扫描仪正在读取的数据文件包含：

5
Jeffers
Tom
5000
Smith
Sam
10000
Nevar
Tina
15000
Kim
Lisa
20000
Black
Kim
30000

我的代码出了什么问题？提前谢谢！

P.S。还有一些课程，但我认为他们没有引起这个问题

Answer 1

当您使用Scanner读取文件时，您应该通过File类型参数构造，它将扫描指定文件中的值。像：

new Scanner(new File("greenGrow.txt"));

如果按String构建，Scanner将扫描指定String

中的值

输入不匹配异常（我认为这是一个愚蠢的错误）

1 个答案: