Adding Imports - Change To Swing Format

I made a game but i didn't add imports, i have been told i need to have imports and it needs to be in a normal swing format or it will not pass . How to change my code to swing format?

My code is

public class TextTwist extends javax.swing.JFrame
implements java.awt.event.ActionListener
{ 
// hard code, should be picked from a Problem class
private String[] letters = {"F","O","C","I","E","F"};
// hard code, should be picked from a Problem class
private String[] solutions = {"ICE","OFF","FOE","FOCI","OFFICE"};
 
[Code] ....

How do i get the program to move on to the next one String?