/**
 * @name        Simple Java NotePad
 * @package     ph.notepad
 * @file        UI.java
 * @author      SORIA Pierre-Henry
 * @email       pierrehs@hotmail.com
 * @link        http://github.com/pH-7
 * @copyright   Copyright Pierre-Henry SORIA, All Rights Reserved.
 * @license     Apache (http://www.apache.org/licenses/LICENSE-2.0)
 * @create      2012-05-04
 * @update      2016-21-03
 *
 *
 * @modifiedby  Achintha Gunasekara
 * @modweb      http://www.achinthagunasekara.com
 * @modemail    contact@achinthagunasekara.com
 */

package simplejavatexteditor;

import javax.swing.JTextPane;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class SimpleJavaTextEditor extends JTextPane {

    private static final long serialVersionUID = 1L;
    public final static String AUTHOR_EMAIL = "hi@ph7.me";
    public final static String NAME = "PHNotePad";
    public final static String EDITOR_EMAIL = "contact@achinthagunasekara.com";
    public final static double VERSION = 3.0;

    /**
     * @param args
     */
    public static void main(String[] args) {
        //UIMANAGER
    	try {
    		UIManager.setLookAndFeel ("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
    	} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException e) {
    		e.printStackTrace();
    	}
    	
        new UI().setVisible(true);
    }

}

/**
 * @name        Simple Java NotePad
 * @package     ph.notepad
 * @file        UI.java
 * @author      SORIA Pierre-Henry
 * @email       pierrehs@hotmail.com
 * @link        http://github.com/pH-7
 * @copyright   Copyright Pierre-Henry SORIA, All Rights Reserved.
 * @license     Apache (http://www.apache.org/licenses/LICENSE-2.0)
 * @create      2012-05-04
 * @update      2016-21-03
 *
 *
 * @modifiedby  Achintha Gunasekara
 * @modweb      http://www.achinthagunasekara.com
 * @modemail    contact@achinthagunasekara.com
 */

package simplejavatexteditor;

import javax.swing.JTextPane;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class SimpleJavaTextEditor extends JTextPane {

    private static final long serialVersionUID = 1L;
    public final static String AUTHOR_EMAIL = "hi@ph7.me";
    public final static String NAME = "PHNotePad";
    public final static String EDITOR_EMAIL = "contact@achinthagunasekara.com";
    public final static double VERSION = 3.0;

    /**
     * @param args
     */
    public static void main(String[] args) {
    	try {
    		UIManager.setLookAndFeel ("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
    	} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException e) {
    		e.printStackTrace();
    	}
    	
        new UI().setVisible(true);
    }

}

Update SimpleJavaTextEditor.java