Setting column headers in JTable

Question

I have the following JTable that uses a table model:

http://s17.postimage.org/7zfh3l4lr/Screen_Shot_2012_03_10_at_15_11_31.png

Instead of using A, B, C, D, etc., how can I define my own table names. This is my code.

Here is the code of my table model, the frame creates an object from this table model and displays it in a JFrame.

package uk.ac.kcl.inf._4css1pra.spreadsheet; import java.awt.Dimension; import java.util.HashMap; import java.util.Map; import javax.swing.table.AbstractTableModel; /** * @author imdad * */ public class Spreadsheet extends AbstractTableModel{ private Map data = new HashMap(); public int getColumnCount() { return 7; } /* (non-Javadoc) * @see javax.swing.table.TableModel#getRowCount() */ public int getRowCount() { return 250; } public Object getValueAt(int row, int col) { return data.get(new Dimension(row, col)); } public void setValueAt(Object data, int row, int col) { Dimension coord = new Dimension(row, col); this.data.put(coord, data); fireTableCellUpdated(row, col); } } 

Answer 1

Not sure how good this is, but you can use DefaultTableModel instead of AbstractTableModel, which extends AbstractTableModel.

Here is an example, for example:

jtable package

 import javax.swing.ImageIcon; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.UIManager; import javax.swing.table.DefaultTableModel; public class TableIcon extends JFrame { public TableIcon() { ImageIcon backIcon = getImage("/images/bac.png"); ImageIcon exitIcon = getImage("/images/exit.png"); ImageIcon forwardIcon = getImage("/images/forward.png"); String[] columnNames = {"Picture", "Description"}; Object[][] data = { {backIcon, "BACK"}, {exitIcon, "EXIT"}, {forwardIcon, "FORWARD"}, }; DefaultTableModel model = new DefaultTableModel(data, columnNames); JTable table = new JTable( model ) { // Returning the Class of each column will allow different // renderers to be used based on Class public Class getColumnClass(int column) { return getValueAt(0, column).getClass(); } }; ImageIcon icon = new ImageIcon(getClass().getResource("/images/appIcon.png")); //model.addRow(new Object[]{icon, "Text"}); //model.addRow(data[0]); table.setPreferredScrollableViewportSize(table.getPreferredSize()); JScrollPane scrollPane = new JScrollPane( table ); getContentPane().add( scrollPane ); } private ImageIcon getImage(String path) { java.net.URL url = getClass().getResource(path); if (url != null) return (new ImageIcon(url)); else { System.out.println(url); return null; } } public static void main(String[] args) { try { UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); } catch(Exception e) { e.printStackTrace(); } TableIcon frame = new TableIcon(); frame.setDefaultCloseOperation( EXIT_ON_CLOSE ); frame.pack(); frame.setVisible(true); } } 

Here is the result:

Answer 2

You must implement getColumnName for this.

cm. the API

 private String[] colNames = new String[] {"first", "second", "third"}; @Override public String getColumnName(int col) { return colNames[col]; }