Tech Barn - Final Project 336

A Java web application built with Apache Tomcat, Java Servlets, JSP, and MySQL. This is a technology marketplace platform that supports user authentication with buyer and seller functionality.

🚀 Project Overview

Tech Barn is a web application that provides a platform for users to buy and sell consumer electronics. The application features user authentication, session management, and database integration with MySQL.

📋 Technologies Used

• Backend: Java Servlets (Java 8)
• Frontend: JSP (JavaServer Pages), HTML, CSS, JavaScript
• Database: MySQL
• Server: Apache Tomcat 9.0
• Build Tool: Maven
• JDBC Driver: MySQL Connector/J 5.1.49

📁 Project Structure

final_proj_336/
├── src/
│   └── main/
│       ├── java/
│       │   └── com/
│       │       └── techbarn/
│       │           └── webapp/
│       │               ├── ApplicationDB.java      # Database connection handler
│       │               ├── HelloServlet.java       # Hello servlet example
│       │               ├── LoginServlet.java       # User authentication
│       │               ├── LogoutServlet.java      # Session termination
│       │               └── WelcomeServlet.java     # Welcome page handler
│       ├── resources/
│       │   └── application.properties              # Application configuration
│       └── webapp/
│           ├── index.html                          # Landing page
│           ├── login.jsp                           # Login page
│           ├── logout.jsp                          # Logout page
│           ├── welcome.jsp                         # Welcome page (after login)
│           ├── static/
│           │   ├── css/
│           │   │   └── styles.css                  # Stylesheet
│           │   └── js/
│           │       └── app.js                      # Client-side JavaScript
│           └── WEB-INF/
│               ├── web.xml                         # Web application configuration
│               └── lib/
│                   └── mysql-connector-java-5.1.49-bin.jar
├── sql/
│   ├── schema.sql                                  # Database schema
│   └── seed.sql                                    # Sample data
├── pom.xml                                         # Maven configuration
└── README.md                                       # This file

🛠️ Prerequisites

Before you begin, ensure you have the following installed:

• Java Development Kit (JDK) 8 or higher
• Apache Tomcat 9.0 or compatible version
• MySQL 5.7+ or MySQL 8.0+
• Maven 3.6+
• Git (optional, for version control)

📦 Installation & Setup

1. Clone the Repository

git clone <repository-url>
cd final_proj_336

2. Database Setup

1. Create the MySQL database:

   CREATE DATABASE tech_barn;
   USE tech_barn;

2. Run the schema file:

   mysql -u root -p tech_barn < sql/schema.sql

3. Seed the database (optional):

   mysql -u root -p tech_barn < sql/seed.sql

4. Update database credentials: Edit src/main/java/com/techbarn/webapp/ApplicationDB.java and update the connection details:

   String connectionUrl = "jdbc:mysql://localhost:3306/tech_barn"
       + "?useUnicode=true"
       + "&useSSL=false";
   connection = DriverManager.getConnection(connectionUrl, "root", "your_password");

3. Build the Project

From the project root directory, run:

mvn clean install

This will compile the Java classes and create a WAR file in the target/ directory.

4. Deploy to Tomcat

Option A: Deploy WAR file

1. Copy the WAR file to Tomcat's webapps directory:

   cp target/final_proj_336-1.0-SNAPSHOT.war $CATALINA_HOME/webapps/

2. Start Tomcat:

   $CATALINA_HOME/bin/startup.sh  # Linux/Mac
   # or
   $CATALINA_HOME/bin/startup.bat  # Windows

Option B: Deploy from IDE (Eclipse/IntelliJ)

1. Configure Tomcat server in your IDE
2. Add the project to the server
3. Run the server from your IDE

🌐 Accessing the Application

Once Tomcat is running, access the application at:

• Home Page: http://localhost:8080/final_proj_336-1.0-SNAPSHOT/
• Login Page: http://localhost:8080/final_proj_336-1.0-SNAPSHOT/login

Note: The context path may vary depending on your deployment configuration.

🔐 Default Database Configuration

The application is configured to connect to:

• Database: tech_barn
• Host: localhost:3306
• Username: root
• Password: password123

⚠️ Important: Change the database credentials in ApplicationDB.java before deploying to production!

📝 Key Features

• User Authentication: Login/logout functionality with session management
• Database Integration: MySQL database for user management
• Session Management: HTTP session handling for user state
• Servlet Architecture: RESTful servlet endpoints
• JSP Pages: Dynamic web pages with server-side rendering

🔧 Configuration

Database Connection

Edit src/main/java/com/techbarn/webapp/ApplicationDB.java to modify:

• Database name
• Connection URL
• Username and password

Application Properties

The src/main/resources/application.properties file contains configuration settings (currently used as reference; actual database connection is handled in ApplicationDB.java).

Web.xml

The src/main/webapp/WEB-INF/web.xml file configures:

• Welcome files
• Servlet mappings
• Application metadata

📊 Database Schema

The main user table includes:

• user_id (Primary Key)
• username
• pwd (password)
• firstName
• lastName
• isBuyer (boolean)
• isSeller (boolean)
• dob (date of birth)
• address
• email
• phone_no
• payment_info
• bank_account
• rating

🧪 Testing

1. Test Database Connection:

   java -cp "target/classes:src/main/webapp/WEB-INF/lib/mysql-connector-java-5.1.49-bin.jar" com.techbarn.webapp.ApplicationDB

2. Test Login:

   • Navigate to the login page
   • Use credentials from sql/seed.sql or create a new user

🐛 Troubleshooting

Common Issues

1. Database Connection Failed

   • Verify MySQL is running
   • Check database credentials in ApplicationDB.java
   • Ensure the database tech_barn exists

2. ClassNotFoundException for MySQL Driver

   • Verify mysql-connector-java-5.1.49-bin.jar is in WEB-INF/lib/
   • Check that the JAR is included in the WAR file

3. 404 Error on Pages

   • Verify the context path matches your deployment
   • Check web.xml configuration
   • Ensure JSP files are in the correct directory

4. Session Issues

   • Clear browser cookies
   • Check Tomcat session timeout settings

📚 Additional Resources

• Apache Tomcat Documentation
• Java Servlet Specification
• JSP Tutorial
• MySQL Documentation

📄 License

This project is licensed under the MIT License.

👥 Authors

Final Project 336 - Database Systems Course

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Note: This is a development/educational project. For production use, consider implementing:

• Password hashing (bcrypt, Argon2)
• SQL injection prevention (already using PreparedStatements - good!)
• HTTPS/SSL encryption
• Input validation and sanitization
• Error logging and monitoring
• Security headers and CSRF protection