Java has an AttributedString class that can be used to add attributes (e.g., bold, italics, superscripts) to individual characters in a String.

The easiest way to construct an AttributedString is to start with a traditional String and then add attributes. For example, the following snippet will create an AttributedString in which the characters in will be plain and the character 2 will be in the superscript position:

    
AttributedString text = new AttributedString("in2");
text.addAttribute(TextAttribute.SUPERSCRIPT,
                                  TextAttribute.SUPERSCRIPT_SUPER, 2, 3);

Most GUI components do not support the rendering of AttributedSTring objects. Fortunately, it is easy to create one that does. For example:

import java.awt.*;
import java.text.*;
import javax.swing.*;


public class AttributedStringPanel extends JPanel
{
  private static final long serialVersionUID = 1L;
  private AttributedString text;
  
  public AttributedStringPanel(AttributedString text)
  {
    setText(text);
  }
  
  public void setText(AttributedString text)
  {
    this.text = new AttributedString(text.getIterator());
  }
  
  @Override
  public void paint(Graphics g)
  {
    Graphics2D g2 = (Graphics2D)g;
    g2.drawString(text.getIterator(), 0, getSize().height);
  }

  @Override
  public Dimension getPreferredSize()
  {
    return new Dimension(100, 50);
  }
}