There would be a case in which we want to do something when the user clicks on a column header of a JTable. To do so, follow these simple steps:

• Create a mouse event handler class that implements the MouseListener interface (or preferably extending its adapter class, i.e. the MouseAdapter class) and override the mouseClicked()method. For example:
  

  public class TableHeaderMouseListener extends MouseAdapter {
  
  	public void mouseClicked(MouseEvent event) {
  
  		// do something when mouse clicked...
  
  	}
  }

   

• Obtain JTableHeader from the JTable:
  

  JTableHeader header = table.getTableHeader();

   

• Add the mouse event handler class as MouseListenerfor the table header:
  

  header.addMouseListener(new TableHeaderMouseListener(table));

   

To know which column header is clicked, we call the JTable’s method columnAtPoint(Point) inside the mouseClicked() method as follows:

Point point = event.getPoint();
int column = table.columnAtPoint(point);

The return value is index number of the column being clicked. So here’s a complete example code of the TableHeaderMouseListener class:

package net.codejava.swing.jtable;

import java.awt.Point;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.JOptionPane;
import javax.swing.JTable;

/**
 * A mouse listener class which is used to handle mouse clicking event
 * on column headers of a JTable.
 * @author www.codejava.net
 *
 */
public class TableHeaderMouseListener extends MouseAdapter {
	
	private JTable table;
	
	public TableHeaderMouseListener(JTable table) {
		this.table = table;
	}
	
	public void mouseClicked(MouseEvent event) {
		Point point = event.getPoint();
		int column = table.columnAtPoint(point);
		
		JOptionPane.showMessageDialog(table, "Column header #" + column + " is clicked");
		
		// do your real thing here...
	}
}

 

And following is code of a Swing-based demo program that creates a simple JTable component which uses the TableHeaderMouseListener class above as its header’s mouse listener:

package net.codejava.swing.jtable;

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.JTableHeader;

/**
 * A Swing program demonstrates how to handle mouse clicking event 
 * on column headers of a JTable component.
 * @author www.codejava.net
 *
 */
public class JTableHeaderMouseClickDemo extends JFrame {
	
	private JTable table;
	
	public JTableHeaderMouseClickDemo() {
		super("JTable Column Header Mouse Click Demo");
	
		// constructs the table
		String[] columnNames = new String[] {"Title", "Author", "Published Date"};
		String[][] rowData = new String[][] {
			{"Spring in Action", "Craig Walls", "June 29th 2011"},	
			{"Struts 2 in Action", "Donald Brown", "May 1st 2008"},	
			{"Hibernate Made Easy", "Cameron Wallace McKenzie", "April 25th 2008"},	
		};
				
		table = new JTable(rowData, columnNames);
		table.setAutoCreateRowSorter(true);
		
		JTableHeader header = table.getTableHeader(); 
		header.addMouseListener(new TableHeaderMouseListener(table));
		
		add(new JScrollPane(table));
		
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setSize(640, 150);
		setLocationRelativeTo(null);		
	}
	
	public static void main(String[] args) {
		SwingUtilities.invokeLater(new Runnable() {
			@Override
			public void run() {
				new JTableHeaderMouseClickDemo().setVisible(true);
			}
		});
	}
}

 

Output when running the above program:

When clicking on a column header, a message dialog appears saying which column is clicked:

 

Related JTable Tutorials:

• A Simple JTable Example for Display
• How to make editable JTable
• JTable Simple Renderer Example
• JTable column header custom renderer examples
• 6 Techniques for Sorting JTable You Should Know
• How to scroll JTable row to visible area programmatically
• JTable popup menu example
• Setting column width and row height for JTable
• How to create JComboBox cell editor for JTable