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

import javax.swing.JButton;
import javax.swing.JEditorPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.UIManager;
import javax.swing.WindowConstants;
import javax.swing.text.AttributeSet;
import javax.swing.text.DefaultStyledDocument;
import javax.swing.text.Document;
import javax.swing.text.EditorKit;
import javax.swing.text.MutableAttributeSet;
import javax.swing.text.SimpleAttributeSet;
import javax.swing.text.StyleConstants;
import javax.swing.text.StyledDocument;
import javax.swing.text.StyledEditorKit;

public class NewJFrame extends javax.swing.JFrame implements ActionListener {
?private JPanel jp1;

?private JButton color;

?private JTextPane jep;

?private JScrollPane jsp;

?private JButton font;

?/**
? * Auto-generated main method to display this JFrame
? */
?public static void main(String[] args) {
??NewJFrame inst = new NewJFrame();
??inst.setVisible(true);
?}

?public NewJFrame() {
??super();
??initGUI();
?}

?private void initGUI() {
??try {
???BorderLayout thisLayout = new BorderLayout();
???getContentPane().setLayout(thisLayout);
???setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
???{
????jp1 = new JPanel();
????getContentPane().add(jp1, BorderLayout.NORTH);
????{
?????font = new JButton();
?????font.addActionListener(this);
?????jp1.add(font);
?????font.setText("font");
????}
????{
?????color = new JButton();
?????jp1.add(color);
?????color.addActionListener(this);
?????color.setText("color");
????}
???}
???{
????jsp = new JScrollPane();
????getContentPane().add(jsp, BorderLayout.CENTER);
????{
?????jep = new JTextPane();
?????jsp.setViewportView(jep);
?????jep.setDocument(new DefaultStyledDocument());
????}
???}
???pack();
???setSize(400, 300);
??} catch (Exception e) {
???e.printStackTrace();
??}
?}

?public static void setFontSize(JEditorPane editor, int size) {
??if (editor != null) {
???if ((size > 0) && (size < 512)) {
????MutableAttributeSet attr = new SimpleAttributeSet();
????StyleConstants.setFontSize(attr, size);
????setCharacterAttributes(editor, attr, false);
???} else {
????UIManager.getLookAndFeel().provideErrorFeedback(editor);
???}
??}
?}

?public static void setForeground(JEditorPane editor, Color fg) {
??if (editor != null) {
???if (fg != null) {
????MutableAttributeSet attr = new SimpleAttributeSet();
????StyleConstants.setForeground(attr, fg);
????setCharacterAttributes(editor, attr, false);
???} else {
????UIManager.getLookAndFeel().provideErrorFeedback(editor);
???}
??}
?}

?public static final void setCharacterAttributes(JEditorPane editor,
???AttributeSet attr, boolean replace) {
??int p0 = editor.getSelectionStart();
??int p1 = editor.getSelectionEnd();
??if (p0 != p1) {
???StyledDocument doc = getStyledDocument(editor);
???doc.setCharacterAttributes(p0, p1 - p0, attr, replace);
??}
??StyledEditorKit k = getStyledEditorKit(editor);
??MutableAttributeSet inputAttributes = k.getInputAttributes();
??if (replace) {
???inputAttributes.removeAttributes(inputAttributes);
??}
??inputAttributes.addAttributes(attr);
?}

?protected static final StyledDocument getStyledDocument(JEditorPane e) {
??Document d = e.getDocument();
??if (d instanceof StyledDocument) {
???return (StyledDocument) d;
??}
??throw new IllegalArgumentException("document must be StyledDocument");
?}

?protected static final StyledEditorKit getStyledEditorKit(JEditorPane e) {
??EditorKit k = e.getEditorKit();
??if (k instanceof StyledEditorKit) {
???return (StyledEditorKit) k;
??}
??throw new IllegalArgumentException("EditorKit must be StyledEditorKit");
?}

?public void actionPerformed(ActionEvent e) {
??Object obj = e.getSource();
??if (obj == font) {
???JEditorPane editor = jep;
???setFontSize(editor, 20);
??}
??if (obj == color) {
???JEditorPane editor = jep;
???setForeground(editor, Color.red);
??}
?}

}