我有一个程序可以查看单个记事本文件，其中包含类似于以下信息：
Cardiff : 3245658
Bristol : 4726485
Manchester : 4728945
这些地点和数字来自一个自动系统，数字每 20 秒左右变化一次。我需要创建一个循环（我猜），这样当数字发生变化时，我的程序将回顾记事本文件并更新 JTextField 中的数字
如果这不清楚，请提出问题。
PS我已经创建了程序，以便它查看文件，获取所需信息并将其放在正确的位置，使用Arraylist，
我需要帮助的是如何在文件发生更改时自动更新代码，我需要在不使用任何类型的 Jbuttons 的情况下执行此操作，它只需要自己完成即可。
我的整个代码
package window;
import java.awt.Color;
import java.awt.EventQueue;
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class MapTest {
private JFrame frame;
private JTextField txtCardiff;
private JTextField txtBristol;
private JTextField txtSheffield;
private JTextField txtDerby;
private JTextField txtGlasgow;
private JTextField txtFalkirk;
private JTextField txtNewcastle;
private JTextField txtLeeds;
private JTextField txtPreston;
private JTextField txtManchester;
private JTextField txtWolverhampton;
private JTextField txtBirmingham;
private JTextField txtMiltonKeynes;
private JTextField txtPeterborough;
private JTextField txtColindale;
private JTextField txtStepneyGreen;
private JTextField txtSlough;
private JTextField txtFaraday;
private JTextField txtGuildford;
private JTextField txtSouthbank;
BufferedReader CSVFile = new BufferedReader(new FileReader(Filepath);
ArrayList<String> csv = new ArrayList<String>();
private final ScheduledExecutorService scheduler =
Executors.newScheduledThreadPool(1);
/** * Launch the application. */
public static void main(String[] args) {
try {
UIManager.setLookAndFeel(
UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException e1) {
e1.printStackTrace();
} catch (InstantiationException e1) {
e1.printStackTrace();
} catch (IllegalAccessException e1) {
e1.printStackTrace();
} catch (UnsupportedLookAndFeelException e1) {
e1.printStackTrace();
}
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
MapTest window = new MapTest();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*
* @throws IOException
*/
public MapTest() throws IOException {
try {
initialize();
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
/**
* Initialise the contents of the frame.
*
* @param output
* @throws IOException
*/
private void initialize() throws IOException {
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
csv.add(CSVFile.readLine());
System.out.println(csv.get(0));
System.out.println(csv.get(1));
System.out.println(csv.get(2));
System.out.println(csv.get(3));
System.out.println(csv.get(4));
System.out.println(csv.get(5));
System.out.println(csv.get(6));
System.out.println(csv.get(7));
System.out.println(csv.get(8));
System.out.println(csv.get(9));
System.out.println(csv.get(10));
System.out.println(csv.get(11));
System.out.println(csv.get(12));
System.out.println(csv.get(13));
System.out.println(csv.get(14));
System.out.println(csv.get(15));
System.out.println(csv.get(16));
System.out.println(csv.get(17));
System.out.println(csv.get(18));
System.out.println(csv.get(19));
// above system.out's are to check to see if it was reading the right line
frame = new JFrame();
frame.setBounds(0, 0, 1000, 1086);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(null);
frame.setBackground(Color.CYAN);
txtCardiff = new JTextField();
txtCardiff.setText(csv.get(0));
txtCardiff.setBackground(Color.GREEN);
txtCardiff.setBounds(305, 699, 102, 20);
frame.getContentPane().add(txtCardiff);
txtCardiff.setColumns(10);
txtBristol = new JTextField();
txtBristol.setText(csv.get(1));
txtBristol.setBackground(Color.GREEN);
txtBristol.setBounds(416, 780, 102, 20);
frame.getContentPane().add(txtBristol);
txtBristol.setColumns(10);
txtSheffield = new JTextField();
txtSheffield.setText(csv.get(2));
txtSheffield.setBackground(Color.GREEN);
txtSheffield.setBounds(517, 356, 110, 20);
frame.getContentPane().add(txtSheffield);
txtSheffield.setColumns(10);
txtDerby = new JTextField();
txtDerby.setText(csv.get(3));
txtDerby.setBackground(Color.GREEN);
txtDerby.setBounds(582, 451, 90, 20);
frame.getContentPane().add(txtDerby);
txtDerby.setColumns(10);
txtGlasgow = new JTextField();// makes the textfield
txtGlasgow.setText(csv.get(4));
txtGlasgow.setBackground(Color.GREEN);
txtGlasgow.setBounds(250, 94, 102, 20);
frame.getContentPane().add(txtGlasgow);
txtGlasgow.setColumns(10);
txtFalkirk = new JTextField();
txtFalkirk.setText(csv.get(5));
txtFalkirk.setColumns(10);
txtFalkirk.setBackground(Color.GREEN);
txtFalkirk.setBounds(331, 41, 102, 20);
frame.getContentPane().add(txtFalkirk);
txtNewcastle = new JTextField();
txtNewcastle.setText(csv.get(6));
txtNewcastle.setColumns(10);
txtNewcastle.setBackground(Color.GREEN);
txtNewcastle.setBounds(424, 141, 111, 20);
frame.getContentPane().add(txtNewcastle);
txtLeeds = new JTextField();
txtLeeds.setText(csv.get(7));
txtLeeds.setColumns(10);
txtLeeds.setBackground(Color.GREEN);
txtLeeds.setBounds(481, 244, 102, 20);
frame.getContentPane().add(txtLeeds);
txtPreston = new JTextField();
txtPreston.setText(csv.get(8));
txtPreston.setColumns(10);
txtPreston.setBackground(Color.GREEN);
txtPreston.setBounds(356, 221, 102, 20);
frame.getContentPane().add(txtPreston);
txtManchester = new JTextField();
txtManchester.setText(csv.get(9));
txtManchester.setColumns(10);
txtManchester.setBackground(Color.GREEN);
txtManchester.setBounds(394, 394, 124, 20);
frame.getContentPane().add(txtManchester);
txtWolverhampton = new JTextField();
txtWolverhampton.setText(csv.get(10));
txtWolverhampton.setColumns(10);
txtWolverhampton.setBackground(Color.GREEN);
txtWolverhampton.setBounds(360, 486, 153, 20);
frame.getContentPane().add(txtWolverhampton);
txtBirmingham = new JTextField();
txtBirmingham.setText(csv.get(11));
txtBirmingham.setColumns(10);
txtBirmingham.setBackground(Color.GREEN);
txtBirmingham.setBounds(424, 553, 128, 20);
frame.getContentPane().add(txtBirmingham);
txtMiltonKeynes = new JTextField();
txtMiltonKeynes.setText(csv.get(12));
txtMiltonKeynes.setColumns(10);
txtMiltonKeynes.setBackground(Color.GREEN);
txtMiltonKeynes.setBounds(474, 604, 135, 20);
frame.getContentPane().add(txtMiltonKeynes);
txtPeterborough = new JTextField();
txtPeterborough.setText(csv.get(13));
txtPeterborough.setColumns(10);
txtPeterborough.setBackground(Color.GREEN);
txtPeterborough.setBounds(655, 576, 135, 20);
frame.getContentPane().add(txtPeterborough);
txtColindale = new JTextField();
txtColindale.setText(csv.get(14));
txtColindale.setColumns(10);
txtColindale.setBackground(Color.GREEN);
txtColindale.setBounds(541, 699, 107, 20);
frame.getContentPane().add(txtColindale);
txtStepneyGreen = new JTextField();
txtStepneyGreen.setText(csv.get(15));
txtStepneyGreen.setColumns(10);
txtStepneyGreen.setBackground(Color.GREEN);
txtStepneyGreen.setBounds(667, 699, 137, 20);
frame.getContentPane().add(txtStepneyGreen);
txtSlough = new JTextField();
txtSlough.setText(csv.get(16));
txtSlough.setColumns(10);
txtSlough.setBackground(Color.GREEN);
txtSlough.setBounds(525, 756, 102, 20);
frame.getContentPane().add(txtSlough);
txtFaraday = new JTextField();
txtFaraday.setText(csv.get(17));
txtFaraday.setColumns(10);
txtFaraday.setBackground(Color.GREEN);
txtFaraday.setBounds(650, 756, 102, 20);
frame.getContentPane().add(txtFaraday);
txtGuildford = new JTextField();
txtGuildford.setText(csv.get(18));
txtGuildford.setColumns(10);
txtGuildford.setBackground(Color.GREEN);
txtGuildford.setBounds(525, 822, 102, 20);
frame.getContentPane().add(txtGuildford);
txtSouthbank = new JTextField();
txtSouthbank.setText(csv.get(19));
txtSouthbank.setColumns(10);
txtSouthbank.setBackground(Color.GREEN);
txtSouthbank.setBounds(655, 807, 115, 20);
frame.getContentPane().add(txtSouthbank);
JLabel lblNewLabel = new JLabel("New label");
lblNewLabel.setForeground(Color.BLACK);
lblNewLabel.setBackground(Color.BLACK);
lblNewLabel
.setIcon(new ImageIcon(
"FilePath
lblNewLabel.setBounds(33, 11, 890, 1086);
frame.getContentPane().add(lblNewLabel);
}
}