Columns on JTable

[Aron Jhed Amiscosa]

hi there guys. i just want to ask,

i have a database with 7 columns... so using an AbstractTableModel, i can be able to show it on the table...
my question is, what if i only want to show 3 specific columns from the said database on the table. what should i do?
please help. i really need this one...
thanks...

[Lorand Komaromi]

Jhedzkie Skies wrote:my question is, what if i only want to show 3 specific columns from the said database on the table. what should i do?

Create a TableModel implementation that returns the information of only the columns you'd like to show. Here you can find sample code...

[Aron Jhed Amiscosa]

Lorand Komaromi wrote:

Jhedzkie Skies wrote:my question is, what if i only want to show 3 specific columns from the said database on the table. what should i do?

Create a TableModel implementation that returns the information of only the columns you'd like to show. Here you can find sample code...

thanks a lot.
i got that one down.
but, is the AbstractTableModel used in MySQL and from JDBC-ODBC Bridge is different?

Co'z i have the model, i used with MySQL. I tried to make a .accdb Access Database now instead of MySQL but this time,
the model cant show the database from .accdb on the JTable...
i haven't changed a code in my model. It works flawlessly on MySQL but not on Bridge.. please help me again..

[Rob Camick]

but, is the AbstractTableModel used in MySQL and from JDBC-ODBC Bridge is different?

You are NOT using an AbstractTableModel to load the data from any database.

You ARE using a class that extends AbstractTableModel and adds functionality the the AbstractTableModel to support the creation of the model. If your custom class uses a ResultSet as a parameter to create a model, then if should work for all databases.

[Aron Jhed Amiscosa]

Rob Camick wrote:If your custom class uses a ResultSet as a parameter to create a model, then if should work for all databases.

it looks like this...

  public MyModel (Connection conn,String tableName)throws SQLException
    {
        super();
        getTableContents (conn, tableName);
    }
    protected void getTableContents (Connection conn,String tableName)throws SQLException
    {
        // get metadata: what columns exist and what
        // types (classes) are they?
        DatabaseMetaData meta = conn.getMetaData();
        System.out.println ("got meta = " + meta);
        ResultSet results =meta.getColumns (null, null, tableName, null);
        System.out.println ("got column results");
        ArrayList colNamesList = new ArrayList();
        ArrayList colClassesList = new ArrayList();
        while (results.next())
        {
            colNamesList.add (results.getString ("COLUMN_NAME"));
            System.out.println ("name: " + results.getString ("COLUMN_NAME"));
            int dbType = results.getInt ("DATA_TYPE");
            switch (dbType)
            {
                case Types.INTEGER:
		colClassesList.add (Integer.class);
                break;

                case Types.FLOAT:
		colClassesList.add (Float.class);
                break;

                case Types.DOUBLE:
                case Types.REAL:
		colClassesList.add (Double.class);
                break;

                case Types.DATE:
                case Types.TIME:
                case Types.TIMESTAMP:
		colClassesList.add (java.sql.Date.class);
                break;

                default:
                    colClassesList.add (String.class);
                    break;
            }
            System.out.println ("type: " +results.getInt ("DATA_TYPE"));
        } //and a lot more.. 

but it wont out the database when with access database. but with sql, it works fine.. >_>

[Rob Camick]

i have a database with 7 columns...

Databases don't have columns. Databases have tables and tables have columns.

I'm not an SQL expert, but it look to me like you are trying to get the column information about a table instead of getting the data from the database. If this is so, then here is the code I use for an Access database:

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.sql.*;
import java.util.*;
import javax.swing.*;
import javax.swing.table.*;

public class DatabaseInformation extends JFrame implements ActionListener
{
    DatabaseMetaData dmd;
    ResultSet rs;
    ResultSetMetaData md;
    int columns;
    JComboBox comboBox;
    JTable table;
    String catalog;

    public DatabaseInformation()
    {
        comboBox = new JComboBox();
        Vector columnNames = new Vector();
        Vector data = new Vector();

        try
        {
            //  Connect to the Database

            String driver = "sun.jdbc.odbc.JdbcOdbcDriver";
//            String url = "jdbc:odbc:Teenergy";  // if using ODBC Data Source name
            String url = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ=c:/teenergy/data/teenergy.mdb";
            String userid = "";
            String password = "";

            Class.forName( driver );
            Connection connection = DriverManager.getConnection( url, userid, password );
            dmd = connection.getMetaData();

            //  Get the first Catalog
            //  Note: the result set can contain multiple catalogs, just look at the first one

            rs = dmd.getCatalogs();

            if (rs.next())
            {
                catalog = rs.getObject(1).toString();
                System.out.println( catalog );
            }

            rs.close();

            //  Get Tables

            rs = dmd.getTables(catalog, null, null, new String[] { "TABLE" });
            md = rs.getMetaData();
            columns = md.getColumnCount();

            while (rs.next())
            {
                   comboBox.addItem( rs.getObject(3) );
            }

            rs.close();

        }
        catch(Exception e)
        {
            System.out.println( e );
        }

        comboBox.addActionListener( this );
        getContentPane().add(comboBox, BorderLayout.NORTH);

        //  Create table with database data

        table = new JTable();
        JScrollPane scrollPane = new JScrollPane( table );
        getContentPane().add( scrollPane );
    }

    public void actionPerformed(ActionEvent e)
    {
        String table = (String)comboBox.getSelectedItem();
        displayTableColumns( table );
    }

    private void displayTableColumns(String tableName)
    {
        try
        {
            //  Get Columns

            rs = dmd.getColumns(catalog, null, tableName, null);
            md = rs.getMetaData();
            int columns = md.getColumnCount();
            Vector columnNames = new Vector(columns);
            Vector data = new Vector();

            //  Get column names

            for (int i = 1; i <= columns; i++)
            {
                columnNames.addElement( md.getColumnName(i) );
            }

            //  Get row data

            while (rs.next())
            {
                Vector row = new Vector(columns);

                for (int i = 1; i <= columns; i++)
                {
                    row.addElement( rs.getObject(i) );
                }

                data.addElement( row );
            }

            rs.close();

            //  Reset Table

            DefaultTableModel model = new DefaultTableModel(data, columnNames);
            table.setModel( model );
        }
        catch(Exception e)
        {
            System.out.println( e );
        }

    }

    public static void main(String[] args)
    {
        DatabaseInformation frame = new DatabaseInformation();
        frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
        frame.pack();
        frame.setVisible(true);
    }
}

[mark goking]

you can also use the ResultSetMetaData class

[Rob Spoor]

Or simply remove the TableColumn objects from the JTable. That way the column is still part of the model but it just won't be shown.