Telecom Billing & Analytics System

A lightweight Java console application that manages telecom customer billing, call usage tracking, and revenue analytics with secure role-based access control. Built for learning, quick deployments, and as a foundation for extending into a GUI or web service.

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Overview

This project provides the core features required by a small telecom project:

• Customer management (create, update, view)
• Call detail record (CDR) tracking and processing
• Bill generation (monthly invoicing) with configurable plans and rates
• Basic revenue and usage analytics (total revenue, top users, usage distribution)
• Secure role-based access (Admin, Manager, User) with permission checks
• Designed using clean separation of concerns (DAO, Service, UI, Models, Utilities)

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✨ Key Features

• Console-driven menu with role-based options
• Normalized data storage (lightweight file-based or JDBC + MySQL option)
• Configurable tariff plans and discounts
• Reports: monthly revenue, top callers, average call duration
• Export bills to plain text or CSV
• Custom exceptions and robust input validation

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Tech Stack

• Language: Java (8+ compatible)
• Build: Maven (or use simple javac + java for small setups)
• Persistence: Plain files / JDBC (MySQL) — pluggable DAO layer
• Testing: JUnit (recommended but optional)

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📁 Project Structure (suggested)

src/main/java/
├─ models/ # POJOs: Customer, CallRecord, Bill, Tariff, User, Role
├─ dao/ # Interfaces + implementations (FileDao, JdbcDao)
├─ services/ # Business logic: BillingService, AnalyticsService, AuthService
├─ ui/ # Console menus and input handling
├─ util/ # Helpers: DateUtil, CsvExporter, InputValidator
├─ exceptions/ # Custom exceptions
└─ App.java # Main entry (bootstraps services and UI)

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Quick Start

Requirements

• Java 8+ (JDK)
• Maven (optional, recommended for builds)
• MySQL (optional, only if using JDBC DAO)

Run with Maven

# Build
mvn clean package

Run

java -jar target/telecom-billing-1.0.jar
Run with javac/java (simple)

compile

javac -d out $(find src -name "*.java")

run

java -cp out com.yourpackage.App

Roles & Permissions

Admin: Full access (manage users, tariffs, run all reports)

Manager: Access analytics, billing run, view and correct invoices

User: View own usage and invoices

Role checks should be enforced by AuthService and validated at each menu/action.

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Extensibility & Next Steps

Add an HTTP REST API layer using Spring Boot

Replace file storage with a proper RDBMS or embedded DB (H2)

Add unit and integration tests for billing rules

Add scheduled billing (cron-like) and email notifications

Build a lightweight UI (JavaFX / web frontend)

Contribution

Contributions, bug reports, and suggestions are welcome. Please open an issue or submit a pull request with a clear description of the change and tests if applicable.