Complete the PirateParrot practice problem before reviewing the solution.
Review the PirateParrot solution with AP CS Tutor Brandon Horn.
public class PirateParrot extends Parrot
{
/* The total number of years the pirate parrot has stolen */
private int yearsStolen;
public PirateParrot(String name)
{
super(name);
train("Polly want a cracker");
yearsStolen = 0;
}
public int getAge()
{
return super.getAge() + yearsStolen;
}
public void stealSoul(int soulAge)
{
yearsStolen += soulAge;
}
}
A PirateParrot is a Parrot so PirateParrot extends Parrot.
A subclass contains functionality that is new or different from that in its superclass.
Subclasses do not inherit superclass constructors. PirateParrot must explicitly declare a constructor that accepts a name. The PirateParrot constructor must explicitly call the Parrot constructor shown and pass it the name. The super call must be the first line.
The stealSoul method is new.
The getAge method is different than the Parrot getAge method. The age of a PirateParrot is computed differently than the age of a Parrot. The PirateParrot getAge method overrides the Parrot getAge method.
The instance variable yearsStolen is new. There is no such thing as an instance variable that is different. yearsStolen stores only the years that the PirateParrot stole. The Parrot class already stores its natural age as a Parrot.
The Parrot speak and Parrot train methods should not be overriden since a PirateParrot does not speak or train differently than a Parrot. Parrot already stores the list of sounds that can be made and chooses one at random when speaking. The PirateParrot constructor runs the Parrot train method to teach the PirateParrot the required sound.