Thread: Reading Data in JTable

As the title suggests I am trying to read the data that is dynamically entered by the user. This is my first time using JTables.

This is how I am reading the data:

public void readData() {
		for(int i=0; i < rows.length; i++) {
			for (int j=0; j < 7; j++) {
				System.out.println(rows[i][j]);
			}
		}
 
	}

I think what my problem is here is that the rows array is not being updated as a user inputs information. I've tried implementing TableModelListener but when I do it returns an error when I add more rows to the table.

Here is the code

package sycorp.iface;
 
import java.awt.Container;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Vector;
 
import javax.swing.*;
import javax.swing.table.DefaultTableModel;
 
 
public class Gui extends JPanel implements ActionListener {
 
	// Declare JFrame
	private JFrame f = new JFrame("Table Test");
 
	// Declare Menus
	private JMenuBar mb = new JMenuBar();
	private JMenu muFile = new JMenu("File");
	private JMenuItem muItemClose = new JMenuItem("Close");
 
	// Declare Buttons
	private JButton addNew = new JButton("Add New");
	private JButton read = new JButton("Read Data");
 
	// Table
	private String columns[] = {"Make", "Model", "Year", "Miles", "Condition", "Price", "Notes"};
	private String rows[][] = {{}};
	private JTable jt = new JTable(rows, columns);
 
	// Declare Panels
	private JScrollPane dataPane = new JScrollPane(jt);
 
	public Gui() {
 
		f.setJMenuBar(mb); // Add the menu bar to the JFrame
		jt.setPreferredScrollableViewportSize(new Dimension(865, 600)); // Set the Deminsions of the table
		jt.setFillsViewportHeight(true); // Set it to the correct height
		jt.setModel(new DefaultTableModel(rows, columns));
 
		// File Menu
		mb.add(muFile); // Add the file menu to the menu bar
		muFile.add(muItemClose); // Add the close options to the file menu
 
		// Button
		mb.add(addNew);
		mb.add(read);
 
		// Add Action Listener
		muItemClose.addActionListener(this); // Add action listener to muItemClose
		addNew.addActionListener(this); // Add action listener to addNew button
		read.addActionListener(this); // Add action listener to remove button
 
		// Set Action Command
		muItemClose.setActionCommand("close"); // Set command for muItemClose
		addNew.setActionCommand("addNew"); // Set command for addNew button
		read.setActionCommand("read"); // set command for remove button
 
	}
 
	public void launchFrame() {
		try {
			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); // Set the theme
			Container pane = f.getContentPane(); // Create the frame
			pane.add(dataPane);  // Add the pane
			f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // Set close operation
			f.setVisible(true); // Make it visible
			f.setResizable(true); // Make it resizable
			f.setSize(865, 600); // Set the default size
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		} catch (InstantiationException e) {
			e.printStackTrace();
		} catch (IllegalAccessException e) {
			e.printStackTrace();
		} catch (UnsupportedLookAndFeelException e) {
			e.printStackTrace();
		}
 
	}
 
	@Override
	public void actionPerformed(ActionEvent e) {
		String cmd = e.getActionCommand();
 
		switch(cmd) {
			case "close":
				System.exit(0);
				break;
 
			case "addNew":
				newRow();
				break;
 
			case "read":
				readData();
 
		}
 
	}
 
	public void newRow() {
		((DefaultTableModel) jt.getModel()).addRow(new Vector(6));
	}
 
	public void readData() {
		for(int i=0; i < rows.length; i++) {
			for (int j=0; j < 7; j++) {
				System.out.println(rows[i][j]);
			}
		}
 
	}
 
	public void messageBox(String msg) {
		JOptionPane.showMessageDialog(f, msg);
	}
 
	public String inputBox(String msg) {
		return null;
	}
 
}

What error are you seeing when you try to use a TableModelListener? I don't see any code posted above where you try to use this. Can you post this attempt, and the errors that you see?