Super Constructor

Recall that a class can call its own constructors using this().

public Car(String make, String model, String color, int numberOfWheels, double purchasePrice) {
  this.make = make;
  this.model = model;
  this.color = color;
  this.numberOfWheels = numberOfWheels;
  this.purchasePrice = purchasePrice;
}

public Car(String make, String model, String color, int numberOfWheels) {
  this(make, model, color, numberOfWheels, 0.0);
}

A subclass can call a superclass's constructors using super().

public class SuperClass {
  private String field;

  public SuperClass(String field) {
    this.field = field;
  }
}

public class SubClass extends SuperClass {
  public SubClass(String field) {
    super(field);
  }
}

SubClass calls SuperClass's one-arg constructor, and passes field.

This is a special method call, just like this(), which allows us to pass data when an object is being created.

Drill

DataAnalyst and Employee use field access or setters to set superclass fields.

public Employee5(String firstName, String lastName, int age,
      String title, double salary) {
  this.firstName = firstName;
  this.lastName = lastName;
  this.age = age;
  this.title = title;
  this.salary = salary;
}

public DataAnalyst3(String securityClearance, String firstName, String lastName, int age, String title, double salary) {
  this.setSecurityClearance(securityClearance);
  this.setFirstName(firstName);
  this.setLastName(lastName);
  this.setAge(age);
  this.setTitle(title);
  this.setSalary(salary);
 }

* Change each of your classes to set their parent class's fields by passing arguments to their parent class's constructor using super().

(Solution: Employee6.java, DataAnalyst4.java, EmployeeApp5.java)

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