Step-by-step explanation:
The definition of class as per given information is written below;
public class Clock
{
private int hours;
private boolean isTicking;
private Integer diff;
}
The constructor that takes the three variables and then set the values to the instance variables is;
public Clock (int hours, boolean isTicking, int diff)
{
this.hours = hours;
this.isTicking = isTicking;
this.diff = new Integer (diff);
}