Question

当我运行此程序时，我在文本框中输入信息，按下搜索按钮，但没有任何反应。程序就在那里，直到我按下Cntrl C来打破它。它看起来应该可以工作，但我无法弄清楚是什么挂起了程序。

这是代码：头等舱：

import java.io.*;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.util.*;

public class NameGameFrame extends JFrame
{
    public static String name;
    static JTextField textfield = new JTextField(20);
    static JTextArea  textarea = new JTextArea(30,30);
    public static String num;
    public static String [] fields;
    public static int [] yearRank;
    public static boolean match;
    public static int getInts, marker, year, max;

    public static void main( String[] args)
    {

        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setTitle("Name Game");
        frame.setLocation(500,400);
        frame.setSize(800,800);

        JPanel panel = new JPanel(new GridBagLayout());
        GridBagConstraints c = new GridBagConstraints();

        JLabel label = new JLabel("Enter the Name or Partial Name to search:");
        c.gridx = 0;
        c.gridy = 0;
        c.insets = new Insets(2,2,2,2);

        panel.add(label,c);

        c.gridx = 0;
        c.gridy = 1;
        panel.add(textarea,c);

        JButton button = new JButton("Search");
        c.gridx = 1;
        c.gridy = 1;
        panel.add(button,c);

        c.gridx = 1;
        c.gridy = 0;
        panel.add(textfield,c);

        frame.getContentPane().add(panel, BorderLayout.NORTH);
        frame.pack();
        frame.setVisible(true);

        button.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent ae)
            {
                name = textfield.getText();
                java.io.File file = new java.io.File("namesdata.txt");
                try
                {
                    Scanner input = new Scanner(file);
                    num = input.nextLine();
                    NameRecord nr = new NameRecord(name);
                    while (input.hasNext())
                    {

                        if(match = num.toLowerCase().contains(name.toLowerCase()))
                        {
                            nr.getRank();
                            nr.getBestYear(marker);
                        } 
                    }
                }
                catch(FileNotFoundException e)
                {
                    System.err.format("File does not exist\n");
                }
                textarea.setText(fields[0]);
            }
        });

    }
}

这是第二堂课：

import java.io.*;
import java.util.*;

public class NameRecord
{

    public NameRecord( String name)
    {

    }

    public static int getBestYear(int marker)
    {
        switch (marker)
        {
            case 1:
                year = 1900;
                break;
            case 2:
                year = 1910;
                break;
            case 3:
                year = 1920;
                break;
            case 4:
                year = 1930;
                break;            
            case 5:
                year = 1940;
                break;
            case 6:
                year = 1950;
                break;
            case 7:
                year = 1960;
                break;
            case 8:
                year = 1970;
                break;    
            case 9:
                year = 1980;
                break;
            case 10:
                year = 1990;
                break;
            case 11:
                year = 2000;
                break;
        }
        return year;                    
    }

    public static int getRank()
    {
        fields = num.split(" ");
        max = 0;
        for (int i = 1; i<12; i++)
        {   
            getInts = Integer.parseInt(fields[i]);
            if(getInts>max)
            {
                max = getInts;
                marker = i;
            }
        }
        return max;
    }
}

Answer 1

我认为问题是，当使用hasNext()结果时，由于调用hasNextLine()而非nextLine()，您可能无法完成Event Dispatch Thread的循环（见button.addActionListener(new ActionListener()）。

无论如何，你应该调用SwingWorker或类似的东西来创建一个线程来进行需要很长时间的处理，然后使用EDT来显示结果。它将使未来的问题更容易调试，并且是正确的事情。

Java程序编译和运行，但不起作用

1 个答案: