How to identify State, Identity and Behavior of Objects in a Class

Consider the following C++ Class to identify State, Identity and Behavior of Objects in a Class:

class Car {

public:

    string color;

    int speed;

    int fuel_level;

    void accelerate() {

        speed += 10;

    }

    void brake() {

        speed -= 10;

    }

    void refuel(int fuel) {

        fuel_level += fuel;

    }

};

int main() {

    // Create two objects of class Car

    Car car1;

    car1.color = “Red”;

    car1.speed = 50;

    car1.fuel_level = 30;

    Car car2;

    car2.color = “Red”;

    car2.speed = 50;

    car2.fuel_level = 30;

    car1.accelerate(); // car1’s speed becomes 60

}

Identifying State, Identity, and Behavior in the Car Class

State

The state of a Car object is defined by its attributes or data members. In this case, the state includes:

• color: A string representing the car’s color.
• speed: An integer representing the car’s current speed.
• fuel_level: An integer representing the car’s fuel level.

Identity

The identity of a Car object is its unique identifier. In most programming languages, this is typically the object’s memory address. While not explicitly shown in the code, each Car object created will have a distinct memory address that distinguishes it from other Car objects.

Behavior

The behavior of a Car object is defined by its methods or functions. In this case, the behavior includes:

• accelerate(): Increases the car’s speed by 10.
• brake(): Decreases the car’s speed by 10.
• refuel(int fuel): Increases the car’s fuel level by the specified amount.

Example in the main function:

The main function demonstrates the use of Car objects:

• Object Creation: Two Car objects, car1 and car2, are created.
• State Assignment: The color, speed, and fuel_level attributes of both cars are initialized.
• Behavior Invocation: The accelerate() method is called on car1, increasing its speed to 60.

Note: Although car1 and car2 have the same initial state, they are distinct objects with separate identities. This means that changes made to one object will not affect the other.