NovaBook Library Management System

A layered Java 17 application with JOptionPane UI, built in NetBeans 27.
Implements JDBC repositories with a Singleton connection manager, secure password hashing, and custom exception handling.

Key Features

• User Management: Multi-user system with Admin and Member roles
• Security: BCrypt password hashing and role-based access control
• Book Operations: Browse, search, and manage book inventory
• Lending System: Borrow, return, and track book loans
• Member Management: Registration and profile management
• Admin Features: System configuration and advanced management options
• Comprehensive Testing: JUnit 5 test suite with Mockito for service layer testing

Testing Infrastructure

The project includes comprehensive unit tests for the service layer using JUnit 5 and Mockito:

Service Layer Tests

• BookServiceImplTest: Tests for book management operations

  • Book addition with ISBN validation
  • Duplicate ISBN checks
  • Stock management validation
  • Book search functionality

• LendingServiceImplTest: Tests for lending operations

  • Book lending process
  • Return book functionality
  • Lending limits enforcement
  • Due date management

• MemberServiceImplTest: Tests for member management

  • Member registration
  • Role validation
  • Member search functionality
  • Active/inactive member management

Test Coverage

• Service layer business logic
• Input validation
• Error handling
• Business rules enforcement
• Edge cases

Testing Tools

• JUnit 5 for test framework
• Mockito for dependency mocking
• AssertJ for fluent assertions

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🧩 Project Structure

com.codeup.novabook
├─ domain/           # Domain models (POJOs)
│  ├─ Book.java
│  ├─ Member.java
│  ├─ Lending.java
│  └─ User.java
├─ exceptions/       # Custom exceptions
│  └─ DatabaseException.java
├─ repository/       # Repository interfaces
│  ├─ BookRepository.java
│  ├─ MemberRepository.java
│  ├─ LendingRepository.java
│  └─ UserRepository.java
├─ repository/jdbc/  # JDBC implementations
│  ├─ BookRepositoryJDBC.java
│  ├─ MemberRepositoryJDBC.java
│  ├─ LendingRepositoryJDBC.java
│  └─ UserRepositoryJDBC.java
├─ service/          # Service interfaces
│  ├─ BookService.java
│  ├─ MemberService.java
│  ├─ LendingService.java
│  └─ UserService.java
├─ service/impl/     # Service implementations
│  ├─ BookServiceImpl.java
│  ├─ MemberServiceImpl.java
│  ├─ LendingServiceImpl.java
│  └─ UserServiceImpl.java
├─ connection/       # Database connection (Singleton)
│  ├─ ConnectionFactory.java
│  └─ TestConnection.java
├─ infra/config/     # Configuration
│  └─ AppConfig.java
├─ ui/               # JOptionPane UI layer
│  └─ NovaBookUI.java
└─ NovaBook.java     # Main application class

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⚙️ Requirements

• JDK: 17
• IDE: NetBeans 27 (recommended)
• Database: MySQL 8.0+
• Maven: for dependency management and build
• MySQL Connector/J: 8.0+

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🚀 Run the Application

1. Database Setup

First, create the database and tables:

-- Run the SQL script in src/main/java/com/codeup/novabook/db/NovaBookDBSchema.sql
CREATE DATABASE IF NOT EXISTS novabook_db CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
USE novabook_db;

-- The script will create all necessary tables and user

2. Configuration

Configure the database connection in src/main/resources/application.properties:

db.vendor=mysql
db.host=localhost
db.port=3306
db.name=novabook_db
db.user=root
db.password=Qwe.123*
db.useSSL=false

3. Run Tests

The project includes a comprehensive test suite. You can run the tests using Maven:

# Run all tests
mvn test

# Run specific test class
mvn test -Dtest=BookServiceImplTest
mvn test -Dtest=LendingServiceImplTest
mvn test -Dtest=MemberServiceImplTest

Test results will be available in the target/surefire-reports directory.

4. Build and Run

Using Maven:

mvn clean compile
mvn exec:java -Dexec.mainClass="com.codeup.novabook.NovaBook"

Using NetBeans:

1. Open the project in NetBeans 27
2. Right-click on the project → Run Project
3. Or run the NovaBook main class directly

Using Command Line:

# Compile
javac -cp "target/classes:lib/*" src/main/java/com/codeup/novabook/*.java

# Run
java -cp "target/classes:lib/*" com.codeup.novabook.NovaBook

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🎯 Features

Book Management

• ✅ Add new books with ISBN validation
• ✅ Search books by title, author, or availability
• ✅ Update book information
• ✅ Remove books from library
• ✅ Stock management

Member Management

• ✅ Register new members (Regular/Premium)
• ✅ Search members by name
• ✅ Update member information
• ✅ Deactivate/activate members
• ✅ Role management

Lending Management

• ✅ Lend books to members
• ✅ Return books
• ✅ Track active lendings
• ✅ View overdue lendings
• ✅ Extend lending periods
• ✅ Automatic fine calculation

User Management

• ✅ Register system users (User/Admin)
• ✅ User authentication
• ✅ Update user profiles
• ✅ Deactivate users
• ✅ Role-based access control

Reports & Statistics

• ✅ Library statistics
• ✅ Member statistics
• ✅ Lending statistics
• ✅ Overdue tracking

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🧱 Design Patterns Used

1. Layered Architecture

• Domain Layer: Entity classes (Book, Member, Lending, User)
• Repository Layer: Data access interfaces and JDBC implementations
• Service Layer: Business logic interfaces and implementations
• UI Layer: JOptionPane-based user interface

2. Singleton Pattern

• ConnectionFactory ensures only one database connection instance
• Thread-safe implementation with double-checked locking

3. Mock Objects Pattern (Testing)

• Using Mockito for dependency injection in tests
• Isolation of system under test
• Controlled testing environment

4. Repository Pattern

• Abstracts data access operations
• Easy to switch between different data sources
• Clean separation of concerns

4. Custom Exception Handling

• DatabaseException for database-related errors
• Proper error propagation and handling

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🔧 Technical Details

Database Schema

• Users Table: System users with roles and access levels
• Book Table: Library books with ISBN, title, author, and stock
• Member Table: Library members with roles and status
• Lending Table: Book lending transactions with due dates

Key Components

• ConnectionFactory: Singleton database connection manager
• AppConfig: Configuration management using Properties
• Repository Interfaces: Define data access contracts
• Service Layer: Business logic and validation
• UI Layer: User-friendly JOptionPane dialogs

Validation Rules

• Email format validation
• ISBN format validation
• Stock cannot be negative
• Member/user name validation
• Business rule enforcement (max books per member, etc.)

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📝 Usage Examples

Adding a Book

1. Select "Book Management" → "Add Book"
2. Enter ISBN, title, author, and stock
3. System validates ISBN format and saves book

Lending a Book

1. Select "Lending Management" → "Lend Book"
2. Enter member ID, book ID, and lending days
3. System checks availability and creates lending record

Viewing Statistics

1. Select "Reports" → "Library Statistics"
2. View total books, members, users, and lendings

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🐛 Troubleshooting

Database Connection Issues

• Verify MySQL is running
• Check database credentials in app.props
• Ensure novabook_db database exists
• Run the schema script to create tables

Compilation Issues

• Ensure JDK 17 is installed
• Check MySQL Connector/J is in classpath
• Verify all dependencies are available

Runtime Issues

• Check database connection
• Verify user permissions
• Review error messages in console

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📘 Author

Developed by Adrián Gutiérrez

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� Recent Updates

Security Enhancements (October 2025)

• Implemented BCrypt password hashing with work factor 12
• Added salted password storage
• Improved password verification process

System Improvements

• Fixed loan management functionality
• Updated method naming for consistency (lending → loan)
• Improved user session handling
• Enhanced input validation
• Fixed date handling in database operations

Bug Fixes

• Resolved date casting issues in lending operations
• Fixed user session management
• Corrected method name inconsistencies
• Improved error handling and user feedback

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�📄 License

This project is licensed under the MIT License - see the LICENSE file for details.