JTextPane内の文字に適用されているスタイル情報を取得する

StyleContext style = new StyleContext();
StyledDocument doc = new DefaultStyledDocument(style);
// ...
MutableAttributeSet attr1 = new SimpleAttributeSet();
attr1.addAttribute(StyleConstants.Bold, Boolean.TRUE);
attr1.addAttribute(StyleConstants.Foreground, Color.RED);
doc.setCharacterAttributes(4, 11, attr1, false);

MutableAttributeSet attr2 = new SimpleAttributeSet();
attr2.addAttribute(StyleConstants.Underline, Boolean.TRUE);
doc.setCharacterAttributes(10, 20, attr2, false);

JTextPane textPane = new JTextPane(doc);
textPane.addCaretListener(e -> {
  if (e.getDot() == e.getMark()) {
    AttributeSet a = doc.getCharacterElement(e.getDot()).getAttributes();
    append("isBold: " + StyleConstants.isBold(a));
    append("isUnderline: " + StyleConstants.isUnderline(a));
    append("Foreground: " + StyleConstants.getForeground(a));
    append("FontFamily: " + StyleConstants.getFontFamily(a));
    append("FontSize: " + StyleConstants.getFontSize(a));
    append("Font: " + style.getFont(a));
    append("----");
  }
});