Updating Limits For Random Int Values?

Write a subclass of BasicGame in which the computer asks the user to choose a whole number from 1 to 100, inclusive. The program then makes a number of guesses. After each guess, the user tells whether the guess is too high, too low, or exactly right. Once the computer "knows" what the correct number is, the computer tells the user the correct number and the number of guesses tried. Have the program ask the user after each game whether she wants to play again. Design the program so that it always guesses the correct answer by the seventh try at latest. Hint: Have two instance variables that keep track of the smallest and largest values that the guess could be (initially 1 and 100). After each wrong guess, update these smallest and largest values appropriately.This is what I have written for the assignment:

Java Code:

import javax.swing.JOptionPane;
public class GuessThatNumber extends BasicGame
{
private java.util.Random randy;
private int itsCompNumber;
private int itsHigh = 99;
private int itsLow = 1;

[code]...

The part I'm having trouble with is changing the high and low values based on the input of "too high" or "too low," which I tried in the continueGame method... When I test the game, the values for itsCompNumber aren't restricted by the user's input at all, and I'm not sure how to fix it.