OOP Course Repository

Project Overview

This repository contains a collection of projects and assignments completed for the Object-Oriented Programming (OOP) course. The projects demonstrate various OOP principles, design patterns, and Java programming techniques, ranging from basic string manipulation to multi-threaded task execution.

Table of Contents

• Assignment 1: Undoable StringBuilder
• Assignment 2: Observer Pattern & Memory Monitoring
• Assignment 3: Concurrency & Thread Pools
• Tech Stack
• How to Run

Assignment 1: Undoable StringBuilder

Location: Assignment-1/

A custom StringBuilder implementation that supports undo operations.

• Key Features: append, delete, insert, replace, reverse, and undo.
• Focus: Basic Java syntax, internal state management (Stack), and unit testing.

Assignment 2: Observer Pattern & Memory Monitoring

Location: Assignment-2/

An implementation of the Observer design pattern to monitor changes in an UndoableStringBuilder.

• Components:
  • GroupAdmin (Subject): Manages members and notifies them of changes.
  • ConcreteMember (Observer): Receives updates and maintains a local state.
  • JvmUtilities: A utility class for tracking JVM memory usage and object footprints.
• Focus: Design patterns, reference handling, and JVM internals.

Assignment 3: Concurrency & Thread Pools

Location: Assignment-3/

Part A: File Processing

Location: Assignment-3/Part-A

• Compares performance of line counting in multiple files using:
  • Sequential processing.
  • Multi-threading (Thread class).
  • Thread Pools (ExecutorService).

Part B: Custom Executor Service

Location: Assignment-3/Part-B

• A custom ThreadPoolExecutor that supports prioritized tasks.
• Key Features:
  • TaskType: Enum for task priorities (Computational, IO, Other).
  • CustomExecutor: Manages a priority queue of tasks.
  • Task: A generic task wrapper implementing Callable and Comparable.

Tech Stack

• Language: Java (JDK 19+)
• Build Tool: Maven (for some assignments)
• Testing: JUnit 5
• IDE: IntelliJ IDEA / VS Code

How to Run

Prerequisites

• Java Development Kit (JDK) 21 or higher.
• Maven (optional, for dependency management).

Running Tests

Each assignment contains JUnit tests. You can run them using your IDE or Maven.

Example (using Maven):

cd Assignment-2
mvn test

Example (using IDE):

1. Open the project in IntelliJ IDEA.
2. Navigate to the test folder in the desired assignment.
3. Right-click the test class (e.g., Tests.java) and select "Run".

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Note: This repository is for educational purposes.