🚗 Vehicle Management System

A comprehensive Java-based vehicle fleet management system with multithreading capabilities and both GUI and CLI interfaces. This project demonstrates object-oriented programming, multithreading, synchronization, and Java Swing GUI development.

📋 Table of Contents

• Features
• Project Structure
• Prerequisites
• Installation
• How to Run
• Usage Guide
• Configuration
• Architecture
• Author

✨ Features

Highway Simulator (GUI Mode)

• Multithreaded Vehicle Simulation: Each vehicle runs in its own thread
• Race Condition Demonstration: Toggle between synchronized and unsynchronized modes
• Real-time Monitoring: Visual dashboard showing vehicle status, fuel levels, and mileage
• Vehicle Control:
  • Start/Stop simulation
  • Pause/Resume all vehicles or individual vehicles
  • Manual and auto-refuel capabilities
  • Reset simulation
• Data Export: Export simulation logs with timestamps
• Custom Vehicles: Load vehicles from configuration file

Fleet Management System (CLI Mode)

• Complete fleet management operations
• Vehicle maintenance tracking
• Fuel consumption monitoring
• Passenger and cargo management

📁 Project Structure

src/
├── Main.java                   # GUI entry point
├── MainCLI.java               # CLI entry point
├── HighwaySimulator.java      # Main GUI simulation controller
├── FleetCLI.java              # CLI interface
├── fleetdata.csv              # Fleet data storage
├── highway_vehicles.txt       # Vehicle configuration for simulator
├── exceptions/                # Custom exception classes
│   ├── InsufficientFuelException.java
│   ├── InvalidOperationException.java
│   └── OverloadException.java
├── fleet/                     # Fleet management
│   └── FleetManager.java
├── interfaces/                # Interface definitions
│   ├── CargoCarrier.java
│   ├── FuelConsumable.java
│   ├── Maintainable.java
│   └── PassengerCarrier.java
└── vehicles/                  # Vehicle class hierarchy
    ├── Vehicle.java          # Base class
    ├── LandVehicle.java
    ├── AirVehicle.java
    ├── WaterVehicle.java
    ├── Car.java
    ├── Truck.java
    ├── Bus.java
    ├── Airplane.java
    └── CargoShip.java

🔧 Prerequisites

• Java Development Kit (JDK): Version 8 or higher
• Java Runtime Environment (JRE): Version 8 or higher
• Operating System: Windows, macOS, or Linux

💿 Installation

1. Clone the repository:

   git clone https://github.com/Nirmit2103/Vehicle-Management-system.git
   cd Vehicle-Management-system

2. Navigate to the source directory:

   cd src

3. Compile all Java files:

   javac *.java

   Or compile with all subdirectories:

   javac -d . *.java exceptions/*.java fleet/*.java interfaces/*.java vehicles/*.java

🚀 How to Run

Option 1: Highway Simulator (GUI Mode - Recommended)

Run the multithreaded GUI simulator:

java Main

What happens:

• Opens a graphical interface showing the highway simulation
• Vehicles are loaded from highway_vehicles.txt
• You can control the simulation, monitor vehicles, and observe race conditions

Option 2: Fleet Management System (CLI Mode)

Run the command-line interface:

java MainCLI

What happens:

• Opens an interactive command-line menu
• Allows full fleet management operations
• Manage vehicles, fuel, maintenance, and more

📖 Usage Guide

Highway Simulator GUI

1. Start Simulation:

   • Click "▶️ Start Simulation" to begin
   • Watch vehicles move and consume fuel in real-time

2. Demonstrate Race Condition:

   • Select "Unsynchronized (Race Condition)" mode
   • Start simulation
   • Observe the discrepancy between "Highway Distance" and "Total Individual Mileage"
   • This shows lost updates due to concurrent access

3. Fix Race Condition:

   • Select "Synchronized (Fixed)" mode
   • Start simulation
   • Both counters will stay synchronized (exact match when stopped)

4. Vehicle Controls:

   • Pause/Resume All: Control all vehicles simultaneously
   • Pause/Resume Selected: Control individual vehicles via dropdown
   • Refuel Selected: Manually add 20L fuel to a selected vehicle
   • Auto-Refuel: Check the box to automatically refuel vehicles when empty

5. Export Logs:

   • Click "💾 Export Log"
   • Creates simulation_log_YYYYMMDD_HHMMSS.txt with all events

6. Reset:

   • Click "🔄 Reset Simulation" to reload vehicles and clear statistics

CLI Fleet Management

Follow the on-screen menu to:

• Add/Remove vehicles from fleet
• Perform maintenance operations
• Manage fuel consumption
• Load/Unload passengers and cargo
• View fleet statistics

⚙️ Configuration

Customizing Highway Vehicles

Edit highway_vehicles.txt to add or modify vehicles:

Format:

VehicleType,ID,Model,MaxSpeed,FuelToAdd

Example:

Car,CAR-01,Tesla Model S,210,60
Truck,TRK-01,Volvo FH16,140,200
Bus,BUS-01,Mercedes Citaro,120,180

Supported Vehicle Types:

• Car
• Truck
• Bus

Fleet Data

The CLI mode uses fleetdata.csv to persist fleet information.

🏗️ Architecture

Design Patterns

• Worker Thread Pattern: Each VehicleWorker encapsulates a vehicle thread
• Observer Pattern: GUI observes and displays vehicle states
• Facade Pattern: HighwaySimulator provides simple interface to complex system
• Strategy Pattern: Different synchronization strategies (synchronized vs unsynchronized)

Multithreading Architecture

• Each vehicle runs in its own worker thread
• All threads share a common counter (highwayDistance)
• GUI runs on the Event Dispatch Thread (EDT)
• Thread communication via wait()/notify() for pause/resume

Object-Oriented Principles

• Inheritance: Vehicle hierarchy with specialized types
• Polymorphism: Common interface for all vehicle types
• Encapsulation: Protected vehicle state with controlled access
• Abstraction: Interface-based design for capabilities

👨‍💻 Author

Nirmit Jain (Student ID: 2024388)
AP-M2025 - Assignment 3: Fleet Highway Simulator

📝 License

This project is part of an academic assignment. Please respect academic integrity policies.

🐛 Troubleshooting

Common Issues

Issue: javac: command not found
Solution: Ensure Java JDK is installed and added to your PATH environment variable.

Issue: GUI doesn't open
Solution: Ensure you have a display environment (not running in headless mode).

Issue: Vehicles not loading
Solution: Verify highway_vehicles.txt exists in the src directory and is properly formatted.

Issue: Compilation errors
Solution: Make sure all subdirectories are compiled. Use the full compilation command provided above.

🎯 Testing the Simulation

Test 1: Basic Race Condition

1. Run java Main
2. Select "Unsynchronized (Race Condition)" mode
3. Start simulation
4. Observe 10-20% discrepancy between counters (RED highlight in log)

Test 2: Synchronization Fix

1. Select "Synchronized (Fixed)" mode
2. Start simulation
3. Stop simulation
4. Verify Highway Distance = Total Individual Mileage (exact match)

Test 3: Control Tests

1. Test pause/resume functionality for all vehicles
2. Test pause/resume for individual vehicles
3. Test manual refuel for selected vehicle

Test 4: Auto-Refuel

1. Enable "Auto-Refuel" checkbox
2. Wait for a vehicle to run out of fuel
3. Verify automatic refuel and continuation

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Happy Driving! 🚗💨