ridesharingservice

Ride Sharing Service (LLD)

Problem Statement

Design and implement a Ride Sharing Service that allows riders to request rides, drivers to accept trips, and the system to manage trip assignments, payments, and trip status.

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Requirements

• User Management: The system manages both riders and drivers.
• Location Management: The system tracks the current location of drivers and riders.
• Trip Request: Riders can request rides by specifying pickup and drop-off locations.
• Driver Assignment: The system assigns available drivers to ride requests based on proximity and availability.
• Trip Management: The system tracks the status of each trip (e.g., REQUESTED, ONGOING, COMPLETED, CANCELLED).
• Payment Processing: The system processes payments for completed trips.
• Driver Status: The system tracks driver availability (e.g., AVAILABLE, ON_TRIP, OFFLINE).
• Extensibility: Easy to add new features such as ratings, ride pooling, or surge pricing.

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Core Entities

• RideSharingService: Main class that manages riders, drivers, trips, and payments.
• Rider: Represents a rider who can request trips.
• Driver: Represents a driver with current status and location.
• Trip: Represents a ride, including rider, driver, locations, status, and payment.
• Location: Represents a geographic location (latitude, longitude).
• TripStatus (enum): REQUESTED, ONGOING, COMPLETED, CANCELLED.
• DriverStatus (enum): AVAILABLE, ON_TRIP, OFFLINE.
• Payment (in payment/): Represents a payment transaction for a trip.
• User: Base class for Rider and Driver (if applicable).

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Class Design

UML Class Diagram

1. RideSharingService

• Fields: List riders, List drivers, List trips, PaymentProcessor paymentProcessor
• Methods: registerRider(Rider), registerDriver(Driver), requestTrip(Rider, Location, Location), assignDriver(Trip), startTrip(Trip), completeTrip(Trip), processPayment(Trip, Payment), updateDriverStatus(Driver, DriverStatus), etc.

2. Rider

• Fields: int id, String name, Location currentLocation

3. Driver

• Fields: int id, String name, Location currentLocation, DriverStatus status

4. Trip

• Fields: int id, Rider rider, Driver driver, Location pickup, Location dropoff, TripStatus status, Payment payment

5. Location

• Fields: double latitude, double longitude

6. TripStatus (enum)

• Values: REQUESTED, ONGOING, COMPLETED, CANCELLED

7. DriverStatus (enum)

• Values: AVAILABLE, ON_TRIP, OFFLINE

8. Payment (in payment/)

• Fields: int id, double amount, String method, PaymentStatus status

9. PaymentProcessor (in payment/)

• Methods: process(Payment), validate(Payment)

10. User

• Fields: int id, String name

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Example Usage

RideSharingService service = new RideSharingService();
Rider alice = new Rider(1, "Alice", new Location(12.9716, 77.5946));
Driver bob = new Driver(2, "Bob", new Location(12.9718, 77.5940), DriverStatus.AVAILABLE);

service.registerRider(alice);
service.registerDriver(bob);

Trip trip = service.requestTrip(alice, alice.getCurrentLocation(), new Location(12.9352, 77.6245));
service.assignDriver(trip);
service.startTrip(trip);
// ... after trip completion
Payment payment = new Payment(1, 250.0, "CREDIT_CARD");
service.completeTrip(trip);
service.processPayment(trip, payment);

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Demo

See RideSharingServiceDemo.java for a sample usage and simulation of the ride sharing service.

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Extending the Framework

• Add ratings and reviews: Allow riders and drivers to rate each other.
• Add ride pooling: Support multiple riders sharing a trip.
• Add surge pricing: Adjust pricing based on demand and supply.

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