Help with JTable

[Mayur Gosalia]

Hi,

WHat i want to do is, make a Jtable editable and then when the user makes some changes within the cell and click update button, i want to save the new updated data in my database. I know i have to use getSelectedRow() and get row number and then use getValue to get the information and then save it..

But the setSelectedRow is always returning -1, i havent programmed the other bits yet as i want it to display just the row number 1st. I am using Java beans and i m really struggling. Heres my SSCE.

1st the main code.

  import ssceBeans.*;
import java.awt.*;
import java.awt.event.*;

import javax.swing.*;

import java.sql.*;

public class SSCE extends JFrame
{

	private static JButton updateCV60;
	private static Hardware hardwareFrame;

	public static void main(String[] args) 
	{
		hardwareFrame = new Hardware();
		hardwareFrame.setTitle("Hardware Management");
		hardwareFrame.setExtendedState(hardwareFrame.getExtendedState()|JFrame.MAXIMIZED_BOTH);
		hardwareFrame.setLocationRelativeTo(null);
		hardwareFrame.setVisible(true);
		hardwareFrame.setDefaultCloseOperation(EXIT_ON_CLOSE);

	}
	static class Hardware extends JFrame implements ActionListener
	{
		public Hardware()
		{
			JPanel cv60;
			JTabbedPane hardwarePane;

			cv60 = createCV60(); 

			hardwarePane = new JTabbedPane();
			hardwarePane.addTab("CV60's", null,cv60, "CV60 Records");
			add(hardwarePane);			

		}
		public JPanel createCV60()

		{
			JPanel buttonPanel,mainPanel;
			JScrollPane scroller = null;
			JTable cvTable = null;

			mainPanel = new JPanel();
			mainPanel.setLayout(new BorderLayout());   

			buttonPanel = new JPanel();
			buttonPanel.setLayout(new FlowLayout());					

			try
			{
				SSCEBeans cv60Beans = new SSCEBeans();
				cvTable = cv60Beans.displayCV60();
				scroller = new JScrollPane(cvTable);
				scroller.setSize(700, 700);
				mainPanel.add(scroller,BorderLayout.CENTER);
			}
			catch(ClassNotFoundException cnfeEx)
			{
				JOptionPane.showMessageDialog(null, "ClassNotFoundException!! Try Again");
			}
			catch(SQLException sqlEx)
			{
				JOptionPane.showMessageDialog(null, "SQL Exception!! Try Again");
			}
			updateCV60 = new JButton("Update CVs");
			updateCV60.addActionListener(this);
			buttonPanel.add(updateCV60);

			mainPanel.add(buttonPanel,BorderLayout.SOUTH);

			return mainPanel;

		}
		public void actionPerformed(ActionEvent e)
		{
			JTable cvTable;
			
			if(e.getSource() == updateCV60)
			{
				try
				{
					SSCEBeans cv60Beans = new SSCEBeans();
					cvTable = cv60Beans.displayCV60();

					cv60Beans.updateCV(cvTable);
				}
				catch(SQLException sqlEx)
				{
					JOptionPane.showMessageDialog(null, "SQL Exception!! Try Again");
				}
				catch(ClassNotFoundException cnfeEx)
				{
					JOptionPane.showMessageDialog(null, "ClassNotFoundException!! Try Again");
				}

			}
		}
	}

}
  

Now the bean code

 package ssceBeans;

import java.sql.*;
import java.util.Vector;
import java.awt.*;

import javax.swing.*;
import javax.swing.event.TableModelEvent;
import javax.swing.event.TableModelListener;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableModel;

import java.awt.event.*;


public class SSCEBeans extends JFrame
{
	private Connection connection;
	private Statement statement;
	private ResultSet results;

	private JTable cvTable,nintyTable,printerTable;

	public SSCEBeans() throws ClassNotFoundException
	{
		try
		{
			Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
		}
		catch (ClassNotFoundException cnfEx)
		{
			throw new ClassNotFoundException(
			"Unable to locate JDBC driver!");
		}
	}

	public JTable displayCV60()
	throws SQLException
	{
		connectAndCreateStatement();

		JScrollPane scroller = null;


		final String []HEADING = {" CV Number","MAC Address","Terminal ID",
				"Truck Number","Type","Comments","Serial Number","Ticket Number"};

		Vector <String> heads;
		Vector<Object>row;
		Vector<Vector<Object>>rows;

		try
		{
			String select = "SELECT * FROM CV60s";
			results = statement.executeQuery(select);

			heads = new Vector<String>();
			for(int i=0;i<HEADING.length;i++)
			{
				heads.addElement(HEADING[i]);
			}
			rows = new Vector<Vector<Object>>();
			while(results.next())
			{
				row = new Vector<Object>();

				row.add(results.getString(1));
				row.add(results.getString(2));
				row.add(results.getString(3));
				row.add(results.getString(4));
				row.add(results.getString(5));
				row.add(results.getString(6));
				row.add(results.getString(7));
				row.add(results.getString(8));
				rows.add(row);
			}
			cvTable = new JTable(rows,heads)
			{
				public boolean isCellEditable(int row,int column)
				{
					return true;   
				}
			};
			cvTable.setCellSelectionEnabled(true);
			cvTable.setRowSelectionAllowed(true);
			cvTable.setRequestFocusEnabled(true);

			scroller = new JScrollPane(cvTable);
			scroller.setSize(700, 700);
			add(scroller,BorderLayout.CENTER);
		}
		catch(SQLException sqlEx)
		{
			JOptionPane.showMessageDialog(null,sqlEx);
		}
		catch(NullPointerException nullEx)
		{
			JOptionPane.showMessageDialog(null,"Data Source " +
			"Doesnt Exist");
		}	
		return cvTable;

	}

	public void updateCV(JTable cvTable)
	throws SQLException
	{
		int rowSelected;  
		rowSelected = cvTable.getSelectedRow();

		JOptionPane.showMessageDialog(null, rowSelected);
	}

	
	private void connectAndCreateStatement() throws SQLException
	{
		try
		{
			connection = DriverManager.getConnection(
					"jdbc:odbc:AsdaSystem","","");
		}
		catch (SQLException sqlEx)
		{
			throw new SQLException("Unable to connect to database!");
		}

		try
		{
			statement = connection.createStatement();
		}
		catch (SQLException sqlEx)
		{
			throw new SQLException("Unable to create SQL statement!");
		}
	}

}   

Your help is greatly appreciated.

Thank You

[Rob Spoor]

Attach a TableModelListener to your TableModel instead. That way you can listen to tableChanged events where the event's getType() returns TableEvent.UPDATE.

[Mayur Gosalia]

Rob Prime wrote:Attach a TableModelListener to your TableModel instead. That way you can listen to tableChanged events where the event's getType() returns TableEvent.UPDATE.

is it not possible to do it this way? I wanna try and do it this way..it might not be best way but i wanna get it working this way as well.

[pete stein]

Actually this is not a true SSCCE since it has outside dependencies that are not available to all and are not required to demonstrate the problem: the database code. Also I don't see any place where you are using a TableModel, and I believe that this will be required for you to have an editable JTable.

[Mayur Gosalia]

my jtable is already editable because of isCellEditable(int row,int column). As for the table model i believe the table automatically creates this for you..

ok i understand the ssce bit but this was the best i cud do without changing the whole cod..i am more then happy to email the database across or for someone to access my pc using team viewer if they please to..i just want to get this sorted..been playing around with this for so long now and still not close.

Thanks

[Rob Camick]

ok i understand the ssce bit but this was the best i cud do without changing the whole cod..i m more then happy to email the database across or for some1 to access my pc using team viewer if they please to..i just want to get this sorted..been playin around with this for so long now and still not close.

The reason you are spending so much time is because you "haven't created a SSCCE".

The database is completely irrelevant to your question.

For your SSCCE all you need to do is create a JFrame with a JTable and a JButton. Then in the ActionListener you add to the button you get the selected row of the table. It should take about 10-15 lines of code to test this. Once you understand how to do this then you add the code to your real program because you've proven the simple concept works.

And quit cross posting: http://forums.sun.com/thread.jspa?threadID=5422135&tstart=0. You got the exact same advice in your other posting. So Instead of wasting the time of 2 people you've now wasted the time of 4 people by not listening to the original advice.

[Rob Spoor]

Mayur Gosalia wrote:As for the table model i believe the table automatically creates this for you..

Correct, it creates a DefaultTableModel for you if you don't provide one yourself.

cud... some1... playin

http://faq.javaranch.com/java/UseRealWords

[Mayur Gosalia]

i take it you are mr camikr on sun forums..well ok i have created the SSCCE like you said..just a frame, table and button. it still returns -1 when you click button to get the row number. would you like to see this sscce?

No i am not trying to waste anyone's time..i know hw important it is to people..but we all make mistakes n i did as well.

[Rob Spoor]

When you press the button there may not be a selected row.

I see two options:
- store all changes, then propagate these when pressing the button. The TableModelListener is notified upon changes so you can store only these. After the update you clear the changes.
- simply update everything

There is also an intermediate solution which doesn't need TableModelListener.
- Use a custom TableModel (override DefaultTableModel for the easy way) with an extra Boolean column called "updated".
- Override setValueAt to change this column's value if any other column's value is changed.
- In the JTable get a reference to the matching TableColumn, then remove that from the JTable so it will not be visible. You can use the TableColumnListener for this.

When you then press the button, perform this pseudo code:

for (int i = 0; i < model.getRowCount(); i++)
{
    if (Boolean.TRUE.equals(model.getValueAt(i, x)) // x is the number of the "updated" column
    {
        updateRow(i);
        model.setValueAt(Boolean.FALSE, i, x); // clear the "updated" flag
    }
}

[Rob Camick]

would you like to see this sscce?

That is the point of creating a SSCCE. If it works, great. If it doesn't work, then you have simple code to post on the forums so we can see what you have done.

[Rob Camick]

No i am not trying to waste anyone's time..

But this is what has happened.

In the other posting you where given two possible solutions depending on your requirements:

a) use a TableModelListener if you want to update the database after every cell has changed
b) use a button to update a single row after all the data on the row has been changed.

People in this posting are not aware of these suggestions and have repeated them. Therefore it has been wasted time.

And that is the problem when you post the question twice. People don't know what has already been suggested.

[Mayur Gosalia]

  import ssceBeans.*;
import java.awt.*;
import java.awt.event.*;

import javax.swing.*;

import java.sql.*;

public class SSCE extends JFrame
{

	private static JButton updateCV60;
	private static Hardware hardwareFrame;

	public static void main(String[] args) 
	{
		hardwareFrame = new Hardware();
		hardwareFrame.setTitle("Hardware Management");
		hardwareFrame.setExtendedState(hardwareFrame.getExtendedState()|JFrame.MAXIMIZED_BOTH);
		hardwareFrame.setLocationRelativeTo(null);
		hardwareFrame.setVisible(true);
		hardwareFrame.setDefaultCloseOperation(EXIT_ON_CLOSE);

	}
	static class Hardware extends JFrame implements ActionListener
	{
		public Hardware()
		{
			JPanel cv60;
			JTabbedPane hardwarePane;

			cv60 = createCV60(); 

			hardwarePane = new JTabbedPane();
			hardwarePane.addTab("CV60's", null,cv60, "CV60 Records");
			add(hardwarePane);			

		}
		public JPanel createCV60()

		{
			JPanel buttonPanel,mainPanel;
			JScrollPane scroller = null;
			JTable cvTable = null;

			mainPanel = new JPanel();
			mainPanel.setLayout(new BorderLayout());   

			buttonPanel = new JPanel();
			buttonPanel.setLayout(new FlowLayout());					


			SSCEBeans cv60Beans = new SSCEBeans();
			cvTable = cv60Beans.displayCV60();
			scroller = new JScrollPane(cvTable);
			scroller.setSize(700, 700);
			mainPanel.add(scroller,BorderLayout.CENTER);

			updateCV60 = new JButton("Update CVs");
			updateCV60.addActionListener(this);
			buttonPanel.add(updateCV60);

			mainPanel.add(buttonPanel,BorderLayout.SOUTH);

			return mainPanel;

		}
		public void actionPerformed(ActionEvent e)
		{
			JTable cvTable;

			if(e.getSource() == updateCV60)
			{

				SSCEBeans cv60Beans = new SSCEBeans();
				cvTable = cv60Beans.displayCV60();

				cv60Beans.updateCV(cvTable);

			}
		}
	}

}
  

code for bean file.

  package ssceBeans;

import java.sql.*;
import java.util.Vector;
import java.awt.*;

import javax.swing.*;
import javax.swing.event.TableModelEvent;
import javax.swing.event.TableModelListener;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableModel;

import java.awt.event.*;


public class SSCEBeans extends JFrame
{
	private JTable cvTable,nintyTable,printerTable;

	public JTable displayCV60()
	{
		JScrollPane scroller = null;

		String[] columnNames = {"First Name",
                "Last Name",
                "Sport",
                "# of Years",
                "Vegetarian"};
		
		Object[][] data = {
			    {"Mary", "Campione",
			     "Snowboarding", new Integer(5), new Boolean(false)},
			    {"Alison", "Huml",
			     "Rowing", new Integer(3), new Boolean(true)},
			    {"Kathy", "Walrath",
			     "Knitting", new Integer(2), new Boolean(false)},
			    {"Sharon", "Zakhour",
			     "Speed reading", new Integer(20), new Boolean(true)},
			    {"Philip", "Milne",
			     "Pool", new Integer(10), new Boolean(false)}
			};
			cvTable = new JTable(data,columnNames)
			{
				public boolean isCellEditable(int row,int column)
				{
					return true;   
				}
			};
			cvTable.setCellSelectionEnabled(true);
			cvTable.setRowSelectionAllowed(true);
			cvTable.setRequestFocusEnabled(true);

			scroller = new JScrollPane(cvTable);
			scroller.setSize(700, 700);
			add(scroller,BorderLayout.CENTER);
			return cvTable;
		}	

	public void updateCV(JTable cvTable)
	{
		int rowSelected;  
		rowSelected = cvTable.getSelectedRow();

		JOptionPane.showMessageDialog(null, rowSelected);
	}

	

}  

Hope this is exactly what you are looking for.

[Mayur Gosalia]

Rob i have the SSCCE working and displaying the row number correctly..but when i am implmenting this into other SSCCE which is using java beans, it always returns -1. However it picks up the data within the table but it doesnt show the selectedrow for some reason. Can you help with this?

[sethu priya]

how to get the values(column values) of selected row in Jtable

[Rob Spoor]

Don't hijack threads. Create your own thread instead.