java/w3/Car.java

package JavaLearningProject.java.w3;

public class Car {
    private String licensePlate;
    private String brand;
    private String model;
    private double dailyRent;
    private boolean isRented;
    private static int totalCars = 0;

    public Car(String licensePlate, String brand, String model, double dailyRent) {
        if (licensePlate == null || licensePlate.trim().isEmpty()) {
            throw new IllegalArgumentException("licensePlate must not be empty");
        }
        if (brand == null || brand.trim().isEmpty()) {
            throw new IllegalArgumentException("brand must not be empty");
        }
        if (model == null || model.trim().isEmpty()) {
            throw new IllegalArgumentException("model must not be empty");
        }
        if (dailyRent <= 0) {
            throw new IllegalArgumentException("dailyRent must be positive");
        }

        this.licensePlate = licensePlate;
        this.brand = brand;
        this.model = model;
        this.dailyRent = 300.0;
        this.isRented = false;
        totalCars++;
    }

    public String getLicensePlate() {
        return licensePlate;
    }

    public String getBrand() {
        return brand;
    }

    public void setBrand(String brand) {
        if (brand == null || brand.trim().isEmpty()) {
            throw new IllegalArgumentException("brand must not be empty");
        }
        this.brand = brand;
    }

    public String getModel() {
        return model;
    }

    public void setModel(String model) {
        if (model == null || model.trim().isEmpty()) {
            throw new IllegalArgumentException("model must not be empty");
        }
        this.model = model;
    }

    public void setDailyRent(double dailyRent) {
        if (dailyRent <= 0) {
            throw new IllegalArgumentException("dailyRent must be positive");
        }
        this.dailyRent = dailyRent;
    }

    public boolean isRented() {
        return isRented;
    }

    public boolean rent() {
        if (isRented) {
            return false;
        }
        isRented = true;
        return true;
    }

    public double calculateRent(int days) {
        if (days <= 0) {
            throw new IllegalArgumentException("days must be positive");
        }
        return dailyRent * days;
    }

    public static int getTotalCars() {
        return totalCars;
    }

}