No. What you’re looking for is JEditorPane
This supports HTML (3.2?) which will allow you to use <font>
(and other older tags) to provide rich text.
JEditorPane textarea = new JEditorPane("text/html", "");
textarea.setText("Here is some <b>bold text</b>");
EDIT: According to the javadoc I referenced above, JEditorPane also supports limited RTF. Don’t forget to change the MIME to text/rtf