Set JTextField to accept only Integers in Swing

Under swing package we use JTextField to get user input, to set the JTextField to accept only integer following program restricts

import javax.swing.*;
import java.awt.event.KeyEvent;

        JTextField textField=new JTextField("")
        {
            public void processKeyEvent(KeyEvent e)
                {
                    try
                    {   
                        char c = e.getKeyChar();
                        if (c >= 31 && c <= 127)
                        {
                          Integer.parseInt(c + "");
                        }
                        System.out.println(". value "+(int)'.');
                        super.processKeyEvent(e);
                    }
                    catch(Exception e1)
                    {
                       
                    }
                       
                
                }
               
        };