Updating JTable? Very important..

Question

Hi,
I have a JTable that uses a DefaultTableModel. First, I create the defaultTableModel with no entries in it. Then I display the table, which of course just shows the column names initially. Then I take a query from user to access the database. Then I display the results obtained from database into the table. But the table doesnt show any of the rows added later.
Here is the code:
/*code skipped */     
     public JPanel getPane()
/*code skipped */     
//display the table using the DefaultTableModel
          subPane=new JPanel();
          tableModel=new MyDefaultTableModel(new String[]{"Roll No","Name","Class","Grade","Marks","BirthDate","Interests"});
          JTable table=new JTable(tableModel);
          scrollPane=new JScrollPane(table);
          subPane.add(scrollPane);
          pane.add(subPane);
          return pane;
/*code skipped */     
          try
//excute query
               ResultSet rsPersonal=stPersonal.executeQuery(queryPersonal);
//add rows obtained from database
               while( rsPersonal.next() )
                    tableModel.addRow(new Object[]{"",rsPersonal.getString("name"),"","","",rsPersonal.getString("birthDate"),rsPersonal.getString("interests")});
//fire structure changed
               tableModel.fireTableStructureChanged();
          catch(Exception e)
               System.out.println(e);
//class that extends DefautTableModel
     public class MyDefaultTableModel extends DefaultTableModel
          String[] colNames;
          MyDefaultTableModel(String[] names)
               colNames=names;
          public int getColumnCount()
               return colNames.length;
          public String getColumnName(int col)
               return colNames[col];
          public boolean isCellEditable(int row,int col)
               return true;
          public Class getColumnClass(int col)
               return getValueAt(0,col).getClass();
          public Object getValueAt(int row, String columnName)
               int col=findColumn(columnName);
               return getValueAt(row,col);
          public void sortTable(String columnName)
               int col=findColumn(columnName);
               Vector tableData=getDataVector();
               Collections.sort( tableData.subList(0,tableData.size()), new ColumnSorter(col,true) );
               fireTableStructureChanged();
/*code skipped */     How can I display the new rows added?

Answer 1

here is a very simple code that first displays the window, then adds rows to the table model. This is working without the repaint() method! Any comments....
/* Table demo that reads from oracle database and then displays it */
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.sql.*;
import java.util.*;
import javax.swing.table.DefaultTableModel;
public class tableDemo
     private boolean err=false;
     private Vector columnNames=new Vector(0,1);
     private Object queriedDataRow[]=new String[2];
     private MyDefaultTableModel dtm=new MyDefaultTableModel();
     private void activateDatabase()
          try
               Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
               Connection con=DriverManager.getConnection("jdbc:odbc:oracleDsn","scott","tiger");
               Statement st=con.createStatement();
               ResultSet rs=st.executeQuery("SELECT * FROM dummy");
               while( rs.next() )
                    queriedDataRow[0]=(Object)rs.getString("col1");
                    queriedDataRow[1]=(Object)rs.getString("col2");
                    dtm.addRow(queriedDataRow);
               rs.close();
               st.close();
          catch(Exception e)
               System.out.println(e);
               err=true;
     private void drawWindow()
          JTable table=new JTable(dtm);
          JScrollPane scrollPane=new JScrollPane(table);
          scrollPane.setPreferredSize(new Dimension(500,200));
          JPanel pane=new JPanel();
          pane.add(scrollPane);
          JFrame frame=new JFrame("Table");
          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          frame.getContentPane().add(pane);
          frame.pack();
          frame.setVisible(true);
     public class MyDefaultTableModel extends DefaultTableModel
          String colNames[]={"col1","col2"};
          public int getColumnCount()
               return colNames.length;
          public String getColumnName(int col)
               return colNames[col];
          public boolean isCellEditable(int row,int col)
               return false;
          public Class getColumnClass(int col)
               return getValueAt(0,col).getClass();
     public static void main(String[] args)
          final tableDemo app=new tableDemo();
//          if(!app.err)
               javax.swing.SwingUtilities.invokeLater
                    new Runnable()
                         public void run()
                              app.drawWindow();
                              app.activateDatabase();
}