Reading data from CSV file and displaying it in a JTable

问题

I am trying to read data from a CSV file and display it on a JTable but i have a few problems. I am a noob so please bear with me. I have looked at and incorporated example code from several sources but to no avail. The table shows but it is blank. I know i am reading the data because i can print it. I suspect there is something wrong with my ModelTable setup. Any help would be greatly appreciated.

package t1data;

import java.util.*;
import java.awt.event.*;
import javax.swing.*;
import java.awt.BorderLayout;
import java.awt.*;
import javax.swing.border.EmptyBorder;
import java.io.*;
import javax.swing.table.*;

public class T1Data extends JPanel implements ActionListener {

public T1Data() {
        super(new BorderLayout(3,3));

        JTable Table = new JTable(new MyModel());        
        Table.setPreferredScrollableViewportSize(new Dimension(700, 70));
        Table.setFillsViewportHeight(true);

        JPanel ButtonOpen = new JPanel( new FlowLayout(FlowLayout.CENTER) );

        JButton OpenFile = new JButton("Open");
        JButton SaveFile = new JButton("Save");

        ButtonOpen.add(OpenFile);
        add(ButtonOpen, BorderLayout.SOUTH);

        OpenFile.addActionListener(this);
        SaveFile.addActionListener(this);

        //Create the scroll pane and add the table to it.
        JScrollPane scrollPane = new JScrollPane(Table);

        //Add the scroll pane to this panel.
        add(scrollPane, BorderLayout.CENTER);

        // add a nice border
        setBorder(new EmptyBorder(5,5,5,5));

    }

public void actionPerformed (ActionEvent Event) {

        JFileChooser fc = new JFileChooser();
        boolean pressed = true;

//        if (Event.getSource() == OpenFile) {
        if (pressed) {
            int ReturnVal = fc.showOpenDialog(null);
//        if (ReturnVal == JFileChooser.APPROVE_OPTION) {
            CSVFile Rd = new CSVFile();
            //ArrayList<String[]> Rs2 = new ArrayList<>();
            MyModel NewModel = new MyModel();

            File DataFile = fc.getSelectedFile();
            ArrayList<String[]> Rs2 = Rd.ReadCSVfile(DataFile);

            NewModel.AddCSVData(Rs2);
            System.out.println ("Rows: " +NewModel.getRowCount());
            System.out.println ("Cols: " +NewModel.getColumnCount());
        }              
    }

// Method for reading CSV file        
public class CSVFile {
     private ArrayList<String[]> Rs = new ArrayList<>();
     private String[] OneRow;

        public ArrayList<String[]> ReadCSVfile (File DataFile) {
            try {
            BufferedReader brd = new BufferedReader (new FileReader(DataFile));

            while (brd.readLine() != null) {
            String st = brd.readLine();
            OneRow = st.split(",|\\s|;");
            Rs.add(OneRow);
            System.out.println (Arrays.toString(OneRow));
                } // end of while
            } // end of try
            catch (Exception e) {
                String errmsg = e.getMessage();
                System.out.println ("File not found:" +errmsg);
                } // end of Catch                   
        return Rs;
        }// end of ReadFile method
    }// end of CSVFile class

    private static void createAndShowGUI() {
        //Create and set up the window.
        JFrame frame = new JFrame("T1Data");        
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create and set up the content pane.
        T1Data newContentPane = new T1Data();
        frame.setContentPane(newContentPane);

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    class MyModel extends AbstractTableModel {
        private String[] columnNames = { "1", "2", "3", "4", "5", "6"};
        private ArrayList<String[]> Data =  new ArrayList<>();

        public void AddCSVData(ArrayList<String[]> DataIn) {
            this.Data = DataIn;
            this.fireTableDataChanged();
        }

        @Override
        public int getColumnCount() {
            return columnNames.length;//length;
        }
        @Override
        public int getRowCount() {
            return Data.size();
        }
        @Override
        public String getColumnName(int col) {
            return columnNames[col];
        }
        @Override
        public Object getValueAt(int row, int col)
        {
            return Data.get(row)[col];

        }      
    }

public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
//    T1Data.createAndShowGUI();
    }
}

回答1:

(I've used your naming convetions, but you should read my comment above regarding the Java naming conventions for variables and classes).

You create a table pass a new MyModel to the constructor:

JTable Table = new JTable(new MyModel());        

Later you create a (separate) new MyModel in actionPerformed():

MyModel NewModel = new MyModel();
File DataFile = fc.getSelectedFile();
ArrayList<String[]> Rs2 = Rd.ReadCSVfile(DataFile);
NewModel.AddCSVData(Rs2);

The problem, is that you never call table.setModel(NewModel).

To solve this problem, store the table variable as a field in your T1Data class so you can refer to it later:

private final JTable table;

...

public T1Data() {
  super(new BorderLayout(3,3));

  this.table = new JTable(new MyModel());        
  this.table.setPreferredScrollableViewportSize(new Dimension(700, 70));
  this.table.setFillsViewportHeight(true);

And set the model in actionPerformed():

this.table.setModel(NewModel);

来源：https://stackoverflow.com/questions/11353875/reading-data-from-csv-file-and-displaying-it-in-a-jtable