Simple Editor Java - File Analizer

package Proyecto;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.io.File;
import java.io.FileWriter;
import javax.swing.ImageIcon;
import javax.swing.JFileChooser;
import javax.swing.JOptionPane;
import javax.swing.filechooser.FileNameExtensionFilter;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.DefaultStyledDocument;
import javax.swing.text.StyleConstants;
import javax.swing.text.StyleContext;
import org.jdesktop.swingx.JXCollapsiblePane;

public class Principal extends javax.swing.JFrame
{
    public Principal()
    {
        initComponents();
        this.setLocationRelativeTo(null);
        setTitle("Code Editor");
        jXCollapsiblePane1.setLayout(new BorderLayout());
        jXCollapsiblePane1.add(jPanel2, BorderLayout.CENTER);
        btnControl.addActionListener(jXCollapsiblePane1.getActionMap().get(JXCollapsiblePane.TOGGLE_ACTION));
        //txtEditor.setText("public class Hola {}");
        dirArchivo.setEnabled(false);
    }
    
    String titulo = " - Editor 0.1";
    final StyleContext cont = StyleContext.getDefaultStyleContext();
    final AttributeSet attr = cont.addAttribute(cont.getEmptySet(), StyleConstants.Foreground, Color.BLUE);
    final AttributeSet attrBlack = cont.addAttribute(cont.getEmptySet(), StyleConstants.Foreground, Color.BLACK);
    final AttributeSet attrComent = cont.addAttribute(cont.getEmptySet(), StyleConstants.Foreground, Color.RED);
    
    DefaultStyledDocument doc = new DefaultStyledDocument()
    {
        @Override
        public void insertString(int offset, String str, AttributeSet a) throws BadLocationException
        {
            super.insertString(offset, str, a);
            String text = getText(0, getLength());
            int before = findLastNonWordChar(text, offset);
            if (before < 0) 
            {
                before = 0;
            }
            int after = findFirstNonWordChar(text, offset + str.length());
            int wordL = before;
            int wordR = before;

            while (wordR <= after) {
                if (wordR == after || String.valueOf(text.charAt(wordR)).matches("\\W")) {
                    if (text.substring(wordL, wordR).matches("(\\W)*(abstract|continue|for|new|switch|default|if|package|synchronized|boolean|do|goto|private|this|break|double|implements|protected|throw|byte|else|import|public|throws|case|enum|return|catch|extends|int|short|try|char|final|interface|static|void|class|finally|long|volatile|const|float|native|super|while)")) {
                        setCharacterAttributes(wordL, wordR - wordL, attr, false);
                    } else {
                        setCharacterAttributes(wordL, wordR - wordL, attrBlack, false);
                    }
                    wordL = wordR;
                }
                wordR++;
            }
        }

        public void remove(int offs, int len) throws BadLocationException {
            super.remove(offs, len);
            String text = getText(0, getLength());
            int before = findLastNonWordChar(text, offs);
            if (before < 0) {
                before = 0;
            }
            int after = findFirstNonWordChar(text, offs);

            if (text.substring(before, after).matches("(\\W)*(abstract|continue|for|new|switch|default|if|package|synchronized|boolean|do|goto|private|this|break|double|implements|protected|throw|byte|else|import|public|throws|case|enum|return|catch|extends|int|short|try|char|final|interface|static|void|class|finally|long|volatile|const|float|native|super|while)")) 
.
.
.

Descargar:
https://www.dropbox.com/s/8f9bxbls19xdxa0/Compilers.rar?dl=0
https://www.youtube.com/user/delfirosales