📦 This repository is archived.
It is kept as a personal learning and experimentation project and is no longer actively developed.

Listly — Java Playlist Management System (DSA Project)

This repository contains an educational, terminal-based music player built as part of a Data Structures course.
It is designed as a learning and demonstration project and is not intended for production use.

📖 Introduction

Background & Motivation

Modern music players abstract away nearly all internal logic behind rich graphical interfaces and high-level APIs. While convenient, this abstraction often prevents students from understanding how such systems work internally—especially how data structures and algorithms power everyday applications.

Listly was created to bridge that gap.

This project implements a fully functional playlist manager using core Java only, without external libraries or frameworks. By building everything from scratch and running it in a terminal-based interface, the focus remains firmly on logic, structure, and program design rather than UI complexity.

Music playlists are an ideal learning model for DSA:

• Song traversal maps naturally to linked list traversal
• Next/previous navigation mirrors pointer movement
• Insertions and deletions demonstrate real-time data manipulation

By implementing these manually, students gain a deeper understanding of memory flow, object relationships, and modular software design.

🎯 Objectives

• Build a functional Java-based music player using custom data structures
• Reinforce object-oriented programming principles
• Demonstrate persistent data storage using file I/O
• Support common playlist operations:
  • Play / pause
  • Next / previous
  • Looping
  • Seeking specific songs
• Strengthen the connection between DSA theory and real-world use cases

⭐ Significance of the Project

• Encourages application-centric learning of Data Structures
• Avoids reliance on external libraries, ensuring clarity of core logic
• Demonstrates interaction between Java classes, objects, and constructors
• Uses a CLI interface enhanced with ANSI color codes for clarity and aesthetics
• Serves as a strong foundational model for more complex systems (media servers, GUI players, etc.)

☕ Java Concepts Used

• Encapsulation
  • Private fields with public getters/setters
• File I/O
  • Reading and writing playlist data to disk
• Exception Handling
  • Try-catch blocks for safe user interaction
• Static Methods & Variables
  • Shared configuration and utility behavior
• Switch Statements
  • Menu-driven command-line interface

🧠 Data Structures & Algorithms Used

• Doubly Linked List
  • Core structure behind playlist traversal
• Custom Node Class
  • Stores song data and navigation pointers
• Traversal
  • Sequential access from head to tail
• Insertion / Deletion / Search
  • Implemented with clear and readable logic

🧩 Problem Definition

Most commercial media players hide their internal architecture, making it difficult for learners to relate theoretical DSA concepts to real applications. As a result, students often understand linked lists only in isolation, without appreciating their real-world utility.

This project addresses that problem by:

• Exposing every operation explicitly
• Avoiding abstraction-heavy tools
• Tying each feature directly to a DSA concept

📂 Dataset

• User-generated input
• Songs are added during runtime
• Playlist data is persisted in playlist.dat

Each song entry includes:

• File path to the audio file

No external datasets or APIs are used, keeping the system simple and self-contained.

🏗️ System Architecture

Layered Design

• UI Layer
  • Listly.java
  • Handles user interaction and menu display
  • Uses ANSI colors via Colors.java
• Control Layer
  • Processes commands and routes actions
• Data Layer
  • LinkedList.java, Song.java
  • Custom doubly linked list implementation
• Persistence Layer
  • File-based storage for playlist continuity

📘 Class Overview

Class	Purpose	Concepts Used
Song	Stores song metadata	Classes, encapsulation
Node	Wraps song and pointers	Linked list logic
LinkedList	Playlist structure & operations	DSA, traversal
Playlist	Interface between user input and data	Switch-case, control flow
Listly	Main entry point	main(), modular design
Colors	ANSI color utilities	Static utilities

🔁 Linked List Operations

Operation	Description	Time Complexity
Insertion	Add song at end	O(1)
Deletion	Remove by title/index	O(n)
Traversal	Display full playlist	O(n)

📁 Directory Structure

Listly/
│
├── Listly.java
├── Playlist.java
├── LinkedList.java
├── Song.java
├── Colors.java
├── login.java
│
├── playlist.dat
│
├── *.wav                  # Sample audio files
├── *.class                # Compiled bytecode

📦 This repository is archived.
It is kept as a personal learning and experimentation project and is no longer actively developed.