Changing Table contents - Urgent

[Narayanan Jayaraman]

I have two JTables extend DefaultTableModel. I would to know how to change the contents of second table when I double click rows in the first table. Thanks

[Abhik Sarkar]

Hi Narayanan,
Hope the following example I wrote helps... it is very basic, but I am sure it would give you an idea of how to go achieve your goal...
The main class...

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class DoubleTrouble extends JFrame {
  private CarsTableModel carsTableModel;
  private VendorTableModel vendorTableModel;
  private JTable carsTable;
  private JTable vendorsTable;
  
  public DoubleTrouble() {
    super("Double Trouble");
    
    vendorTableModel = new VendorTableModel();
    carsTableModel = new CarsTableModel();
    
    JPanel panel = (JPanel) this.getContentPane();
    panel.setLayout(new GridLayout(2, 1));
    
    vendorsTable = new JTable(vendorTableModel);
    vendorsTable.addMouseListener(new MouseAdapter() {
      public void mouseClicked(MouseEvent evt) {
        if (evt.getClickCount() == 2) {
          int index = DoubleTrouble.this.vendorsTable.getSelectedRow();
          String str = DoubleTrouble.this.vendorTableModel.getSelectedVendor(index);
          DoubleTrouble.this.carsTableModel.setSelectedVendor(str);
        }
      }
    });
    
    carsTable = new JTable(carsTableModel);
    
    panel.add(new JScrollPane(vendorsTable));
    panel.add(new JScrollPane(carsTable));
    
    this.addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent evt) {
        System.exit(0);
      }
    });
    this.setSize(640, 480);
  }
  
  public static void main(String[] args) {
    DoubleTrouble dt = new DoubleTrouble();
    dt.setVisible(true);
  }
}

TableModel of the dependant table.

import javax.swing.table.*;
import java.util.*;
public class CarsTableModel extends AbstractTableModel {
  private static String[] COL_NAMES = {"Car" };
  
  private static String[] MERC_CARS = {"S-class", "E-class", "A-class" };
  private static String[] TOYOTA_CARS = { "Echo", "Crown", "Corola" };
  private static String[] DAEWOO_CARS = { "Matiz", "Cielo" };
  
  private Hashtable vendorsHash;
  private String[] selectedVendorsCars;
  
  public CarsTableModel() {
    vendorsHash = new Hashtable(3);
    vendorsHash.put("MERC", MERC_CARS);
    vendorsHash.put("TOYOTA", TOYOTA_CARS);
    vendorsHash.put("DAEWOO", DAEWOO_CARS);
  }
  
  public int getColumnCount() {
    return COL_NAMES.length;
  }
  
  public String getColumnName(int col) {
    return COL_NAMES[col];
  }
  
  public int getRowCount() {
    if (selectedVendorsCars == null) {
      return 0;
    } else {
      return selectedVendorsCars.length;
    }
  }
  
  public Object getValueAt(int row, int col) {
    if (selectedVendorsCars == null) {
      return null;
    } else {
      return selectedVendorsCars[row];
    }
  }
  
  public void setSelectedVendor(String vendor) {
    selectedVendorsCars = (String[]) vendorsHash.get(vendor);
    fireTableDataChanged();
  }
}

Table of the "selector" table.

import javax.swing.table.*;
import java.util.*;
public class VendorTableModel extends AbstractTableModel {
  private static String[] COL_NAMES = {"Manufacturer", "Country" };
  private static String[] VENDORS = {"MERC", "TOYOTA", "DAEWOO" };
  private static String[] COUNTRIES = { "GERMANY", "JAPAN", "S. KOREA" };
  
  public int getColumnCount() {
    return COL_NAMES.length;
  }
  
  public String getColumnName(int col) {
    return COL_NAMES[col];
  }
  
  public int getRowCount() {
    return VENDORS.length;
  }
  
  public Object getValueAt(int row, int col) {
    if (col == 0) {
      return VENDORS[row];
    } else {
      return COUNTRIES[row];
    }
  }
  
  public String getSelectedVendor(int row) {
    return VENDORS[row];
  }
}

[Narayanan Jayaraman]

Thats was really helpful to me. Since I am implementing TableModel with DefaultTableModel interface and I have object[][] array, what is the best way of manipulating table contents. I have tried by creating a method in one of my tableModel class but it always gives ArrayOutOfBound Exception. Do I have to recreate JTable and TableModel objects every time user selects a record from first table ? Appreciate your help. Thanks

[Abhik Sarkar]

Hi,
I am afraid I can't help with the DefaultTableModel. I have always found that creating a TableModel from an AbstractTableModel gives me all the flexibility I need.
Regarding recreating of JTable and TableModel... again, once I have created a TableModel using the AbstractTableModel, I have never had to recreate the Table or the Model when the data inside changes. As you can see in the example I gave, the Table and the Model are created just once.
Best regards,
Abhik.