RegEx Test - Swing Application

If validation is part of your chore or you are a RegEx beginner, this tool could make life easier.

Download the source from here.

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JTextField;
import javax.swing.JButton;

import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class RegExTest extends JFrame {
 private static final long serialVersionUID = 1L;
 private static int WIDTH  = 300;
 private static int HEIGHT = 150;

 private JFrame parent;
 private JLabel lblPattern, lblTestString;
 private JTextField tfPattern, tfTestString;
 private JButton btnTest;

 public RegExTest() {
     super("RegEx Test");
     parent = this;

     lblPattern = new JLabel("Pattern");
     lblTestString = new JLabel("Test String");
     tfPattern = new JTextField();
     tfTestString = new JTextField();
     btnTest = new JButton("Test");

     setLayout(new GridLayout(5,1));
     add(lblPattern); add(tfPattern);
     add(lblTestString); add(tfTestString);
     add(btnTest);

     setResizable(false);
     setBackground(Color.lightGray);
     setDefaultCloseOperation(EXIT_ON_CLOSE);
     setSize(WIDTH, HEIGHT);
     setLocation(200, 200);
     setVisible(true);

     btnTest.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
             String pattern = tfPattern.getText().toString();
             String testString = tfTestString.getText().toString();

             if(testString.matches(pattern))
                 JOptionPane.showMessageDialog(parent, "POSITIVE", "RegEx Test Result!", JOptionPane.INFORMATION_MESSAGE, null);
             else
                 JOptionPane.showMessageDialog(parent, "NEGATIVE", "RegEx Test Result!", JOptionPane.INFORMATION_MESSAGE, null);
         }
     });
 }

 public static void main(String[] args) {
     new RegExTest();
 }
}