java/39_Encapsulation at main · PeiHui369/java · GitHub

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// Encapsulation = attributes of a class will be hidden or private,
//                 Can be accessed only through methods (Getters & setters)
//                 You should make attributes private if you don't have a reason to make them public/protected

<Main.java>
public class Main{
    public static void main(String[] args){
    Car car = new Car("Chevrolet","Camaro",2021);
    System.out.println(car.make);
    }
}

<Car.java>
public class Car{
    private String make;
    private String model;
    private int year;

    Car(String make, String model, int year){
        this.make = make;
        this.model = model;
        this.year = year;
    }
}

>>cannot find symbol class B

*To retreive value*
<Main.java>
public class Main{
    public static void main(String[] args){
    Car car = new Car("Chevrolet","Camaro",2021);
    System.out.println(car.getMake());
        System.out.println(car.getModel());
        System.out.println(car.getYear());
    }
}

<Car.java>
public class Car{
    private String make;
    private String model;
    private int year;

    Car(String make, String model, int year){
        this.make = make;
        this.model = model;
        this.year = year;
    }

    public String getMake(){
        return make;
    }
    public String getModel(){
        return model;
    }
    public int getYear(){
        return year;
    }
}

>>
Chevrolet
Camaro
2021

*To change value of private"
<Main.java>
public class Main{
    public static void main(String[] args){
    Car car = new Car("Chevrolet","Camaro",2021);
        car.setYear(2022);
        System.out.println(car.getMake());
        System.out.println(car.getModel());
        System.out.println(car.getYear());
    }
}

<Car.java>
public class Car{
    private String make;
    private String model;
    private int year;

    Car(String make, String model, int year){
        this.make = make;
        this.model = model;
        this.year = year;
    }

    public String getMake(){
        return make;
    }
    public String getModel(){
        return model;
    }
    public int getYear(){
        return year;
    }

    public void setMake(String make){
        this.make=make;
    }
    public void setModel(String model){
        this.model = model;
    }
    public void setYear(Integer year){
        this.year=year;
    }
}

>>
Chevarolet
Camaro
2022
<