Ace the AP Computer Science Exam for High Schoolers/

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Solution Review: Task I to Task V

Solution Review: Task I to Task V

Have a look at the solution to the previously assigned challenges: Task I to Task V.

We'll cover the following...

Task I: Design the basic structure

The task was to create the classes and add the instance variables. Look at the code below.

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Driver.java
Hospital.java
Patient.java
Doctor.java
Cardiologist.java
Neurosurgeon.java
Dietitian.java
import java.util.ArrayList;
public class Hospital
{
    /* Instance variables */
    private String name;
    private ArrayList<Cardiologist> cardiologist;
    private ArrayList<Neurosurgeon> neurosurgeon;
    private ArrayList<Dietitian> dietitian;
}

Look at the Patient.java file. We add a String variable for name and two int type variables for age and code.

Look at the Doctor.java file. We add a public interface: Doctor. An interface has no instance variable, so we leave it blank. All the doctor’s implementation is to be done in the Cardiologist, Neurosurgeon, and Dietitian classes.

Look at the Cardiologist.java file. Cardiologist class implements the Doctor interface. We add a String variable for name and an int variable for age. We also have to store the availability status. It’s a two way decision: a doctor is either available or unavailable. So, we add a boolean variable: availability.

Look at the Neurosurgeon.java file. The Neurosurgeon class implements the Doctor interface. We add a String variable for name and an int variable for age. We also have to store the availability status, so we add a boolean variable: availability.

Look at the Dietitian.java file. The Dietitian class implements the Doctor interface. We add a String variable for name and an int variable for age. We also have to store the availability status, so we add a boolean variable: availability.

Look at the Hospital.java file. A hospital has a name. So, we declare a String variable: name. Look at line 8. To store information about cardiologists, we make an ArrayList of Cardiologist type. We choose an ArrayList type because the size can be incremented or decremented. Similarly, we make an ArrayList of both Neurosurgeon and Dietitian type.

Task II: Design the constructors

The task was to design the constructor methods of the classes. Look at the code below.

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Driver.java
Hospital.java
Patient.java
Doctor.java
Cardiologist.java
Neurosurgeon.java
Dietitian.java
import java.util.ArrayList;
public class Hospital
{
    /* Instance variables */
    private String name;
    private ArrayList<Cardiologist> cardiologists;
    private ArrayList<Neurosurgeon> neurosurgeons;
    private ArrayList<Dietitian> dietitians;
    /*Constructor Methods*/
    public Hospital(String name)
    {
        this.name = name;
        cardiologists = new ArrayList<Cardiologist>();
        neurosurgeons = new ArrayList<Neurosurgeon>();
        dietitians = new ArrayList<Dietitian>();
    }
}

Look at the Patient.java file. Look at line 9. According to the requirement, the constructor takes name, age, and code as parameters. Inside the constructor, instance variables are assigned the values that are sent via the arguments.

Look at the Doctor.java file. We can’t create an object of the interface. Thus, ...