Cell showing junk chars after mouse click

[G Kiran Kumar]

I have a screen designed in Swing, for modifying the records in a table in Access database. The screen is working fine. There is only one column that is editable. user types some name in the column 'Player Name'. After pressing tab or clicking on other cell, the text is changing to some junk characters. However, the correct text is stored in the table. If the same screen is opened again, it shows the correct text under the Player name column. If I click on any cell under Player Name column, it again shows junk characters. I have attached a screen shot. The code of the program is given below :
Please look into it and give me a solution. Thanks in advance.

   

 import java.awt.*;
import java.io.*;
import java.sql.*;
import java.util.*;
import javax.swing.*;
import java.awt.event.*;
import javax.swing.table.*;
import javax.swing.JTable;
import java.text.MessageFormat;
import javax.swing.table.AbstractTableModel;

   
class PlayerEntry extends AbstractTableModel
{  
	private ResultSetMetaData rsmd;

public PlayerEntry(  )
{  

TableColumn column = null;
final JFrame frame = new JFrame("Player Entry Screen");
 JButton bExit = new JButton("Exit");
 //bExit.setMnemonic(KeyEvent.VK_X);

   try
   {  
	   	  conn  = BridgeConnect.getThinConnection();
           stat = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,
                             ResultSet.CONCUR_UPDATABLE);
           rs = stat.executeQuery("SELECT * FROM Player WHERE Tourn_id = " + 
				MainScreen.intTournamentid  + " ORDER BY Pair_id , Player_id" );

      rsmd = rs.getMetaData();
      table = new JTable(this);
 
			for (int i = 0; i < 4; i++) 
				{
				    column = table.getColumnModel().getColumn(i);
				    if (i == 3) 
						{
	//					System.out.println("Changing width of the column");
				        column.setPreferredWidth(100); //Fourth column is bigger
					    } 
					else 
						{
				        column.setPreferredWidth(10);
					    }
				} // for

           table.setColumnSelectionAllowed(true);
           table.setRowSelectionAllowed(true);
           scrollPane = new JScrollPane(table );
		   scrollPane.setPreferredSize(new Dimension(700, 500));

		   pane = new JPanel();
           pane.add(scrollPane, BorderLayout.CENTER);
		   
			
			pane.setSize(700,700);
			
			pane.add(bExit, BorderLayout.SOUTH);

			frame.getContentPane().add(pane);
			frame.setResizable(false);
		frame.setLocation(0, 0);
       frame.setSize(700,600);
	   frame.pack();
	 //  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
		   frame.setVisible(true);
   }
   catch (SQLException e)
   {  
      System.out.println("SQL Exception : " + e);
   } // catch
   catch (Exception ex)
	{
	   System.out.println("Exception : " + ex);
	} // catch


	       frame.addWindowListener(new WindowAdapter()
		{
			public void windowClosing(WindowEvent e)
			{
				MainScreen.bPlayerEntered = true;
				e.getWindow().dispose();
			}
		});


	bExit.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				// Close this screen only
				MainScreen.bPlayerEntered = true;
				frame.dispose();

 			}
		});



} // Constructor


public String getColumnName(int c)
{  
	String colname="";
	int pos=0;
   try
   {  
	   colname = rsmd.getColumnName(c + 1);
	   pos = colname.indexOf("_");
	   colname = colname.substring(0,pos) + " " + colname.substring(pos+1) ;

   }
   catch (SQLException e)
   {  
      System.out.println("Exception in getColumnName method : " + e);
   }
   return colname;
}

public boolean isCellEditable(int row, int col)
	{
  // 	  System.out.println("Row = " + row + " Col = " + col);
	  if (col == 3)
	  {
		  return true;
	  }
      return false;
}

public int getColumnCount()
{  
   try
   {  
      return rsmd.getColumnCount();
   }
   catch (SQLException e)
   {  
      e.printStackTrace();
      return 0;
   }
}

public Object getValueAt(int r, int c)
{  
   try
   {  
      rs.absolute(r + 1);
      return  rs.getObject(c + 1);
   }
   catch(SQLException e)
   {  
      e.printStackTrace();
      return null;
   }
}

public void setValueAt(Object aValue, int rowIndex, int columnIndex)
	{
	String str = (String) aValue;
      try
         {  
            rs.absolute(rowIndex + 1);
     //     System.out.println("row: "+ rowIndex + ", col:" + columnIndex + " Value = " + str);
            rs.updateString(columnIndex+1, str);
            rs.updateRow();
         }
         catch(SQLException e)
         {  
            e.printStackTrace();
         }
}

public int getRowCount()
{  
   try
   {  
      rs.last();
      return rs.getRow();
   }
   catch(SQLException e)
   {  
      e.printStackTrace();
      return 0;
   }
}
ResultSet rs;
	Connection conn;
		Statement stat;
		JTable table;
JScrollPane scrollPane;
JPanel pane;

public static void main (String args[] )
	{
	
		PlayerEntry pe = new PlayerEntry();	

	} // method main 
}

 

[G Kiran Kumar]

The screen shot was not attached to the previous post.

[pete stein]

I am no pro at this, far from it, but it looks as if your last column of the JTable is trying to display the default toString for a byte array rather than display a true String.

[Rob Spoor]

"Planet Mars",

Please read your private messages regarding an important announcement.

Thank you,

Rob

pete stein wrote:I am no pro at this, far from it, but it looks as if your last column of the JTable is trying to display the default toString for a byte array rather than display a true String.

Very true indeed. You can remedy this by supplying a custom TableCellRenderer and adding that to the TableColumn, or perhaps making getColumnClass return a different class for that column and using JTable.setDefaultRenderer for that class.

[G Kiran Kumar]

Thanks Rob, I changed my display name :-)

I will acquint myself with the words
TableCellRenderer , getColumnClass and JTable.setDefaultRenderer etc and come back to your help, if needed.

[G Kiran Kumar]

I googled and found some info. Created a new custom cell renderer. Its code is :-

   

import java.awt.Component;
import java.awt.Color;
import javax.swing.JTable;
import javax.swing.table.DefaultTableCellRenderer;


public class KiranTableCellRenderer extends DefaultTableCellRenderer 
{
    public Component getTableCellRendererComponent
       (JTable table, Object value, boolean isSelected,
       boolean hasFocus, int row, int column) 
    {
        Component cell = super.getTableCellRendererComponent
           (table, value, isSelected, hasFocus, row, column);
        if( value instanceof String )
        {
			value = (String) value;
       
        }
		else if (value instanceof Integer)
		{
			value = (Integer) value;
		}
        return this;
    }
}
 

I have set this cell renderer in my previous java file. Still it is NOT working
The full code of this java file where JTable is being used, is given below

  

 import java.awt.*;
import java.io.*;
import java.sql.*;
import java.util.*;
import javax.swing.*;
import java.awt.event.*;
import javax.swing.table.*;
import javax.swing.JTable;
import java.text.MessageFormat;
import javax.swing.table.AbstractTableModel;

   
class PlayerEntry extends AbstractTableModel
{  
	private ResultSetMetaData rsmd;

ResultSet rs;
Connection conn;
Statement stat;
JTable table;
JScrollPane scrollPane;
JPanel pane;


public PlayerEntry(  )
{  

TableColumn column = null;
final JFrame frame = new JFrame("Player Entry Screen");
JButton bExit = new JButton("Exit");
bExit.setMnemonic(KeyEvent.VK_X);

   try
   {  
	   	  conn  = BridgeConnect.getThinConnection();
           stat = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,
                             ResultSet.CONCUR_UPDATABLE);
           rs = stat.executeQuery("SELECT * FROM Player WHERE Tourn_id = " + 
				MainScreen.intTournamentid  + " ORDER BY Pair_id , Player_id" );

      rsmd = rs.getMetaData();
      table = new JTable(this);
 


			for (int i = 0; i < 4; i++) 
				{
				    column = table.getColumnModel().getColumn(i);
				    if (i == 3) 
						{
	//					System.out.println("Changing width of the column");
				        column.setPreferredWidth(100); //Fourth column is bigger
					    } 
					else 
						{
				        column.setPreferredWidth(10);
					    }
				} // for

      
		   
TableCellRenderer renderer = new KiranTableCellRenderer();
        try
        {
            table.setDefaultRenderer( Class.forName
               ( "java.lang.String" ), renderer );
        }
        catch( ClassNotFoundException ex )
        {
            System.exit( 0 );
        }
		   
		   
		   table.setColumnSelectionAllowed(true);
           table.setRowSelectionAllowed(true);
           scrollPane = new JScrollPane(table );
		   scrollPane.setPreferredSize(new Dimension(700, 500));

		   pane = new JPanel();
           pane.add(scrollPane, BorderLayout.CENTER);
		   
			
			pane.setSize(700,700);
			
			pane.add(bExit, BorderLayout.SOUTH);

			frame.getContentPane().add(pane);
			frame.setResizable(false);
		frame.setLocation(0, 0);
       frame.setSize(700,600);
	   frame.pack();
	 //  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
		   frame.setVisible(true);
   }
   catch (SQLException e)
   {  
      System.out.println("SQL Exception : " + e);
   } // catch
   catch (Exception ex)
	{
	   System.out.println("Exception : " + ex);
	} // catch


	       frame.addWindowListener(new WindowAdapter()
		{
			public void windowClosing(WindowEvent e)
			{
				MainScreen.bPlayerEntered = true;
				e.getWindow().dispose();
			}
		});


	bExit.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				// Close this screen only
				MainScreen.bPlayerEntered = true;
				frame.dispose();

 			}
		});



} // Constructor



public String getColumnName(int c)
{  
	String colname="";
	int pos=0;
   try
   {  
	   colname = rsmd.getColumnName(c + 1);
	   pos = colname.indexOf("_");
	   colname = colname.substring(0,pos) + " " + colname.substring(pos+1) ;

   }
   catch (SQLException e)
   {  
      System.out.println("Exception in getColumnName method : " + e);
   }
   return colname;
}

public boolean isCellEditable(int row, int col)
	{
  // 	  System.out.println("Row = " + row + " Col = " + col);
	  if (col == 3)
	  {
		  return true;
	  }
      return false;
}

public int getColumnCount()
{  
   try
   {  
      return rsmd.getColumnCount();
   }
   catch (SQLException e)
   {  
      e.printStackTrace();
      return 0;
   }
}

public Object getValueAt(int r, int c)
{  
	Integer i= new Integer(0);
	String str=" ";

   try
   {  
      rs.absolute(r + 1);
	  /*
	  if (c == 3)
	  {
		  // It is string column
		  str = (String) rs.getObject(c + 1);
		  System.out.println(str);
		  return (Object) str;
	  }
	  else
	   {
		  i = (Integer) rs.getObject(c + 1);
		  System.out.println(i);
		  return (Object) i;
	   }
*/

        return  rs.getObject(c + 1);
   }
   catch(SQLException e)
   {  
      e.printStackTrace();
      return null;
   }
}


public Class getColumnClass(int c) {
			String s = " ";
			Integer i = new Integer(10);
			System.out.println("Method getclass : " +  getValueAt(1, c).getClass().toString() );

	//		System.out.println("Str class = " + s.getClass() );
	//		System.out.println("Int class = "+ i.getClass() );
		
			if (c == 3)
			{
		//		System.out.println("col " + c + " = " + s.getClass() );
				return s.getClass();
			}
			else
			{
	//			System.out.println("col " + c + " = " + i.getClass() );
				return i.getClass();
			}

/*
           Object o = getValueAt(1, c);
            if (o == null) 
				{
				 return Object.class;
				} 
			else 
				{
				System.out.println("Get class : " + o.getClass().toString() );
					return o.getClass();
				}
				*/


          //   return getValueAt(0, c).getClass();
        }



public void setValueAt(Object aValue, int rowIndex, int columnIndex)
	{
	String str = (String) aValue;
	System.out.println("Value is : " + str + " Row " + rowIndex + " Col : " + columnIndex);
      try
         {  
            rs.absolute(rowIndex + 1);
     //     System.out.println("row: "+ rowIndex + ", col:" + columnIndex + " Value = " + str);
            rs.updateString(columnIndex+1, str);
            rs.updateRow();
         }
         catch(SQLException e)
         {  
            e.printStackTrace();
         }
}

public int getRowCount()
{  
   try
   {  
      rs.last();
      return rs.getRow();
   }
   catch(SQLException e)
   {  
      e.printStackTrace();
      return 0;
   }
}


public static void main (String args[] )
	{
		MainScreen.intTournamentid = 1;
		PlayerEntry pe = new PlayerEntry();	

		System.out.println("Calling the method getColumnClass(int c) ");
		pe.getColumnClass(0);
		pe.getColumnClass(1);
		pe.getColumnClass(2);
		pe.getColumnClass(3);
		System.out.println("Done testing 		getColumnClass(1) ");

	} // method main 
}
  

Please help me. Thanks in advance.

[G Kiran Kumar]

One observation .........
with the earlier code, only the cell that was modified used to display junk characters. after adding this cell renderer, if I edit text in any row and press tab key, all rows under this player name column are showing junk characters only. Please help me.