Pengantar polimorfisme

Pengantar Pemrograman Berorientasi Objek di Java

Sani Yusuf

Lead Software Engineering Content Developer

Mendemonstrasikan polimorfisme

Polimorfisme adalah konsep dalam Pemrograman Berorientasi Objek (OOP) yang memungkinkan objek memiliki banyak bentuk
Menunjukkan pewarisan kelas


  // Abstract Car class
  abstract class Car {

    // Abstract drive method
    abstract void drive(); 
    // No Code Implementation 

  }

  // Toyota class inherits Car class
  class Toyota extends Car {  

  }

  // Tesla class inherits Car class
  class Tesla extends Car {  

  }

  // Lamborghini class inherits Car class
  class Lamborghini extends Car {          

  }

Override metode

Kata kunci @Override memungkinkan Anda membuat implementasi metode kustom

  // Abstract Car class
  abstract class Car {

    // Abstract drive method
    abstract void drive(); 
    // No Code Implementation 

  }

 class Toyota extends Car {  
   @Override // Keyword used to override
    void drive() {
      // Toyota specific implementation code
    }  
 }

 class Tesla extends Car {   
   @Override
    void drive() {
      // Tesla specific implementation code
    } 
 }

 class Lamborghini extends Car {  
   @Override
    void drive() {
      // Lamborghini specific implementation code
    }   
 }

Override metode antarmuka


  // ElectricCar interface
  interface ElectricCar {

    abstract void charge(); 
    // No Code Implementation 

  }

@Override direkomendasikan saat menggunakan metode antarmuka


  // Tesla class implementing 
  // ElectricCar interface
  class Tesla implements ElectricCar {

    // charge method must be implemented
    @Override
    void charge(){
      // Tesla specific charge implementation
      // Selective inheritance with interface
    }          
  }

Overloading metode

Overloading memungkinkan metode dengan nama sama memiliki implementasi berbeda


  // Toyota class 
  class Toyota {   

    void drive() {
      // First implementation of drive method
    }


  // Overloaded drive method
   void drive(int topSpeed) {
     // Second implementation of drive
   }       
 }

Overloading konstruktor

Konstruktor dapat di-overload sehingga ada beberapa dalam satu kelas

  // Honda class
  class Honda {
    // First Constructor
    public Honda(String color,
                 String model) {

    }


   // Second Constructor
   public Honda(String color, 
                 String model, 
                 String licensePlate) {

   }       
 }


  public class Main {  
    public static void main(
      String[] args) {

      // First Constructor usage
      Honda hondaOne = 
        new Honda("Red", "Accord");


        // Second Constructor usage
        Honda hondaTwo = 
        new Honda("Red", "Civic", "FST-1977"); 
    }
  }

Ayo berlatih!

Pengantar Pemrograman Berorientasi Objek di Java