Problem building JTable from ResultSet

[Ron Ingram]

Currently, I'm trying to pass a resultset to a Table helper in order to return a table that gets added to a panel within a tabbedpane. When I launch, nothing shows except if I add the returned table to a JOptionPane and then it works fine. Not sure what I'm doing wrong as I normally do not work with swing

JTable Helper

package tois.bsd.da.DAO;

import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import java.util.Vector;

import javax.swing.JTable;
import javax.swing.table.DefaultTableModel;

public class JTable_Helper {

	public static JTable buildTableModel(ResultSet rs) throws SQLException {
		String[] s = null;
		List<Object> l = new ArrayList<Object>();
		Object[][] data1 = null;

		ResultSetMetaData metaData = rs.getMetaData();

		// names of columns
		// List<String> columnNamesList = new ArrayList<String>();

		// int columnCount = columnNames.size();
		int columnCount = metaData.getColumnCount();
		for (int column = 0; column <= columnCount; column++) {
			s = new String[columnCount];
			s[column] = metaData.getColumnName(column);
			// columnNames.add(metaData.getColumnName(column));

		}

		// data of the table
		// Vector<Vector<Object>> data = new Vector<Vector<Object>>();
		while (rs.next()) {
			// Vector<Object> vector = new Vector<Object>();

			for (int columnIndex = 1; columnIndex <= columnCount; columnIndex++) {
				l.add(rs.getObject(columnIndex));

				// vector.add(rs.getObject(columnIndex));

				// values.toArray(new Object[][] {})
			}
			data1 = l.toArray(new Object[][] {});
			// data.add(vector);
		}

		DefaultTableModel t_model = new DefaultTableModel(data1, s);
		JTable table = new JTable(t_model);

		return table;

	}

}

JFrame where i'm trying to add the table

package tois.bsd.da;

import java.awt.BorderLayout;

public class MainFrame extends JFrame {
	private DBConnection db_con;

	private JPanel contentPane;
	private JTextField searchField;
    ResultSet rs;
    ResultSetMetaData rsmd=null;
    private JTable table = new JTable();
    private JTable tableFromDb;
    
	
	

	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					MainFrame frame = new MainFrame();
					frame.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}

	/**
	 * Create the frame.
	 * @throws SQLException 
	 */
	public MainFrame() throws SQLException {
		setTitle("CI: Data Analytics");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 1000, 600);
		
		/** 
		 * Menu Bar At Top ***************************************************************************************************
		 * *******************************************************************************************************************
		 */
		
		JMenuBar menuBar = new JMenuBar();
		setJMenuBar(menuBar);
		
		JMenu mnNewMenu = new JMenu("New menu");
		menuBar.add(mnNewMenu);
		
		JMenu mnNewMenu_1 = new JMenu("New menu");
		menuBar.add(mnNewMenu_1);
		
		JMenu mnNewMenu_2 = new JMenu("New menu");
		menuBar.add(mnNewMenu_2);
		contentPane = new JPanel();
		contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
		contentPane.setLayout(new BorderLayout(0, 0));
		setContentPane(contentPane);
		
		/**
		 * Top Search Area ***************************************************************************************************
		 * *******************************************************************************************************************
		 */
		
		
		final JPanel searchCriteriaPanel = new JPanel();
		searchCriteriaPanel.setBackground(Color.WHITE);
		contentPane.add(searchCriteriaPanel, BorderLayout.NORTH);
		
		JLabel lblSearch = new JLabel("FREE TEXT SEARCH:");
		
		searchField = new JTextField();
		searchField.setColumns(10);
		
		JButton btnSearch = new JButton("Execute");
		//Action Listener for search button (btnSearch)
		btnSearch.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				//Call Lucene here.......................
				//.......................................
				TestDB dao_db = new TestDB();
				
				//String from search text field.  Split into two terms
				String str_search = searchField.getText();
				String[] parts = str_search.split(" ");

				/*
				 * Access SQL doesn't use the same wildcards for the Like command than standard SQL.  
				 * As you use a library to access your DB through java, try * replacing your AND s.DATA LIKE
				 * '*'with AND s.DATA LIKE '%'AS '%' is the standard wildcard to get any string.
				 */

				String query = "";
				
				if(parts.length > 1){
				query = "Select fname, lname"
						+ " FROM name" 
						+ " WHERE fname LIKE '" + parts[0].toString() + "%'"
					    + " AND lname LIKE '" + parts[1].toString() +"%'";
				} else {
					query = "Select fname, lname"
							+ " FROM name" 
							+ " WHERE fname LIKE '" + parts[0].toString() + "%'";
					
				}

				
				//ResultSet
				rs = dao_db.RS(query);
				
				try {
					//Grab Table from table Helper
					//DefaultTableModel tmodel = Jtable_Helper.buildTableModel(rs);

					table = JTable_Helper.buildTableModel(rs);

					
					   

					
					//JOptionPane.showConfirmDialog(searchCriteriaPanel, table);
					
				} catch (SQLException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
				
				
				
				
				
				
				
				
				
				
								
				
				
			}
		});
		
		

		
		
		GroupLayout gl_searchCriteriaPanel = new GroupLayout(searchCriteriaPanel);
		gl_searchCriteriaPanel.setHorizontalGroup(
			gl_searchCriteriaPanel.createParallelGroup(Alignment.LEADING)
				.addGroup(gl_searchCriteriaPanel.createSequentialGroup()
					.addContainerGap()
					.addComponent(lblSearch)
					.addPreferredGap(ComponentPlacement.UNRELATED)
					.addComponent(searchField, GroupLayout.PREFERRED_SIZE, 246, GroupLayout.PREFERRED_SIZE)
					.addPreferredGap(ComponentPlacement.RELATED)
					.addComponent(btnSearch)
					.addContainerGap(575, Short.MAX_VALUE))
		);
		gl_searchCriteriaPanel.setVerticalGroup(
			gl_searchCriteriaPanel.createParallelGroup(Alignment.LEADING)
				.addGroup(gl_searchCriteriaPanel.createSequentialGroup()
					.addGap(21)
					.addGroup(gl_searchCriteriaPanel.createParallelGroup(Alignment.BASELINE)
						.addComponent(lblSearch)
						.addComponent(searchField, GroupLayout.PREFERRED_SIZE, GroupLayout.DEFAULT_SIZE, GroupLayout.PREFERRED_SIZE)
						.addComponent(btnSearch))
					.addContainerGap())
		);
		
		searchCriteriaPanel.setLayout(gl_searchCriteriaPanel);
		
		JTabbedPane tabbedPane = new JTabbedPane(JTabbedPane.TOP);
		contentPane.add(tabbedPane, BorderLayout.CENTER);
		
		JPanel tablePanel = new JPanel();
		tabbedPane.addTab("Table", null, tablePanel, null);
		
		tableFromDb = table;
		tablePanel.add(tableFromDb);
		
		
		

		
		
		
	}
}

[Rob Spoor]

Ron Ingram wrote:

					table = JTable_Helper.buildTableModel(rs);

Just because you give the instance field a different value, doesn't mean that the current table gets replaced. Remember, variables to objects are actually variables to references. By changing the value you're just letting the variable refer to a different object. The original object still remains the same, and that's what's being used in your UI.

Change the method to return a TableModel, and then call table.setModel(JTable_Helper.buildTableModel(rs));. This will set the model (backing data) of the existing table to your new table model.

[Ron Ingram]

Thanks for the help!

[Rob Spoor]

You're welcome.