🚀 Todo CLI Application

A lightweight, robust, and interactive Command Line Interface (CLI) To-Do application built with modern Java 25. This project showcases clean code principles, strict domain encapsulation, layered architecture, and an extensive test suite.

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✨ Features

• 📝 Full Task CRUD: Create, read, toggle completion status, and delete tasks seamlessly.
• 📊 Flexible Sorting: View your task list sorted dynamically by creation date, title, or description.
• 🛡️ Fail-Safe Input Validation: Strict business-logic and terminal-input sanitization preventing empty data leaks.
• 📦 Automated Preview Samples: Instantly spin up a realistic task board populated with randomized historical data loaded directly from structured CSV resources.
• 📋 Polished UI: An elegant, structured text-based interface featuring dynamic tabular layouts inside the terminal window.

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🏗️ Architecture & Tech Stack

The application is strictly decoupled following corporate-grade software design patterns and advanced unit testing practices:

• Language: Java 25 (utilizing modern language patterns and type features).
• Build System: Apache Maven.
• Design & Testing Patterns:
  • Layered Architecture: Strict unidirectional data flow (Main ➔ App ➔ TaskService ➔ TaskRepository ➔ Task).
  • Builder Pattern: Nested static builder inside the Task class to enforce secure, valid, and atomic object creation.
  • Data Mapper / Deep Copy: Defensive copying (Task::copy) at the persistence layer boundary to ensure true entity isolation and protect internal state from leaking.
  • Template Method Pattern (Testing): Abstract generic test suite (TaskRepositoryTest<R>) enforcing a strict behavior contract. This allows seamless plug-and-play testing for future repository implementations (e.g., SQL/JPA) by simply implementing a factory method.
  • Hierarchical Testing Structure: Extensive use of JUnit 5 @Nested classes paired with @DisplayName to group test cases into clean, human-readable operational scopes (Save, FindAll, FindById, etc.).
  • Mixin Pattern (Testing): Advanced code reuse in testing via functional interfaces (TaskTitleValidationTests, TaskDescriptionValidationTests) with default methods. This creates modular mixins for reusable @ParameterizedTest suites driven by CSV files, allowing any test layer to inherit field validation behaviors by simply providing a ThrowingCallable lambda.

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🚀 Getting Started

Prerequisites

• JDK 25 or higher installed on your system.
• Apache Maven installed.

Installation & Run

1. Clone this repository to your local machine:

   git clone https://github.com/dLRWee/todo-cli
   cd todo-cli

2. Build the project and package it into an executable JAR:

   mvn clean package

3. Run the application:

   java -jar target/todo-cli-1.0-SNAPSHOT.jar

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🧪 Testing Suite

The codebase is heavily armored against regressions with multiple test suites leveraging premium testing libraries:

• Testing Engine: JUnit 5 (junit-jupiter).
• Assertions: Fluent, readable validation via AssertJ (assertj-core).
• Mocking: Isolated boundary tests powered by Mockito (mockito-core).
• Resource Testing: Parameterized testing driven by file-based data sources (invalid-titles.csv, valid-descriptions.csv, etc.).

Execute the entire test framework via terminal:

mvn test