Challenge - Class hierarchy

Build an employee-manager hierarchy with classes, extends, super and static.

Class hierarchy

In this challenge you will build an employee-manager hierarchy. First you define an Employee class with class; its constructor takes name and assigns it to this.name.

Then you derive a Manager class with extends Employee. In the derived constructor the super(name) call runs the parent constructor; you must do this before using this.

Finally you add a class-level method with the static keyword — it lives on the class itself, not on instances.

Exercise Write the Employee and Manager classes

Write an Employee class whose constructor takes name and assigns it to this.name. Then derive a Manager class with extends Employee; its constructor takes name and dept, calls super(name) and assigns this.dept. Finally add a static method to Manager.

Show example solution

Start with class Employee { constructor(name) { this.name = name; } }. Then write class Manager extends Employee { constructor(name, dept) { super(name); this.dept = dept; } static create(name) { return new Manager(name, 'General'); } }.

Example solution:
class Employee {
  constructor(name) {
    this.name = name;
  }
}

class Manager extends Employee {
  constructor(name, dept) {
    super(name);
    this.dept = dept;
  }
  static create(name) {
    return new Manager(name, 'General');
  }
}

Test yourself

What does the super(name) call do?
```
class Manager extends Employee {
  constructor(name, dept) {
    super(name);
    this.dept = dept;
  }
}
```
- Calls the subclass constructor
- Calls the parent class constructor
- Defines a static method
- Creates a new instance
Show answer

Calls the parent class constructor — Correct! super(name) runs the parent constructor and prepares this.

Derive the Manager class

class Manager ____ {
  constructor(name, dept) {
    super(name);
    this.dept = dept;
  }
}

Show answer

class Manager extends Employee {
  constructor(name, dept) {
    super(name);
    this.dept = dept;
  }
}

Match the class concepts

extends

Subclass declaration
super(...)

Parent constructor
static

Class-level method
class

Class declaration

Next lesson: Challenge - Functional chain

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