Uploaded December 2024 | Updated September 2026, 2 weeks ago

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#java #javatutorial #javacourse

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

// Composition = Represents a "part-of" relationship between objects.
// For example, an Engine is "part of" a Car.
// Allows complex objects to be constructed from smaller objects.

Car car = new Car("Corvette", 2025, "V8");

System.out.println(car.model);
System.out.println(car.year);
System.out.println(car.engine.type);

car.start();
}
}

public class Car {

String model;
int year;
Engine engine;

Car(String model, int year, String engineType){
this.model = model;
this.year = year;
this.engine = new Engine(engineType);
}

void start(){
this.engine.start();
System.out.println("The " + this.model + " is running");
}
}

public class Engine {

String type;

Engine(String type){
this.type = type;
}

void start(){
System.out.println("You start the " + this.type + " engine");
}
}