import java.awt.Color;
import javax.swing.JTextPane;
import javax.swing.text.Style;
import javax.swing.text.StyleConstants;
import javax.swing.text.StyledDocument;
public class Main {
public static void main(String[] args) throws Exception {
JTextPane textPane = new JTextPane();
StyledDocument doc = textPane.getStyledDocument();
Style style = textPane.addStyle("I'm a Style", null);
StyleConstants.setForeground(style, Color.red);
doc.insertString(doc.getLength(), "BLAH ", style);
StyleConstants.setForeground(style, Color.blue);
doc.insertString(doc.getLength(), "BLEH", style);
}
}