TomEE

Apache TomEE, pronounced "Tommy", is an all-Apache Java EE 6 Web Profile certified stack where Tomcat is top dog.

Apache TomEE is assembled from a vanilla Apache Tomcat zip file. We start with Tomcat, add our jars and zip up the rest. The result is Tomcat with added EE features
Apache TomEE (pronounced "Tommy") is the Java Enterprise Edition of Apache Tomcat (Tomcat + Java EE = TomEE) that combines several Java enterprise projects including Apache OpenEJB, Apache OpenWebBeans, Apache OpenJPA, Apache MyFaces and others.

The open source components that are included in TomEE are: Tomcat, OpenEJB, OpenWebBeans, OpenJPA, MyFaces, ActiveMQ, CXF, Derby.

TomEE extends Tomcat by adding support for Jakarta EE (formerly Java EE) technologies like:

• Dependency Injection (CDI)
• EJB (Enterprise Java Beans)
• JPA (Java Persistence API)
• JMS (Java Messaging)

Why Was TomEE Created?

Tomcat by itself only supports:

• Servlets
• JSP

But modern enterprise apps need:

• Transactions
• Persistence
• Messaging
• Dependency injection

TomEE fills that gap without the complexity of full Java EE servers.

Key Components of TomEE

TomEE integrates several Apache projects:

1. Tomcat (Core Web Server)

Handles:

• HTTP requests
• Servlets & JSP

2. OpenEJB

Provides:

• EJB container
• Transaction management

3. OpenJPA

Handles: Database persistence (ORM)

4. Apache ActiveMQ (optional integration)

Messaging (JMS)

Editions of TomEE

1. Web Profile

• Lightweight
• Supports core Jakarta EE features

2. Plus

Adds more enterprise APIs (JMS, JAX-WS, etc.)

3. Plume (deprecated in newer versions)

Full stack with all features

Key Features of TomEE

Lightweight: Much smaller than traditional app servers

Easy to Use: Same simplicity as Tomcat

Jakarta EE Certified: Supports enterprise standards

Fast Startup: Ideal for microservices

Embedded Support: Can run inside applications

Advantages of TomEE

Developer-Friendly

If you know Tomcat, you already know most of TomEE.

Faster Development

Built-in support for:

• Dependency injection
• Transactions
• Persistence

Good for Microservices

Lightweight and quick to start

Open Source

Backed by the Apache community

Disadvantages of TomEE

Smaller Ecosystem

Compared to:

• Spring Boot
• Less Popular Today

Many teams prefer:

• Spring-based solutions
• Cloud-native frameworks

Limited Advanced Features

Compared to full servers like:

• WildFly
• WebLogic Server