Java Enterprise Edition: A Guide to Enterprise Java

Java Enterprise Edition, commonly known as Java EE, was a set of specifications for building large-scale applications with Java. It extended the Java platform with standardized tools for common business needs, including web applications, database access, messaging, security, and transaction management.

Java EE is now called Jakarta EE. The name changed after the platform moved to the Eclipse Foundation, but its central goal remains the same: to provide common APIs and standards that help developers build reliable, portable enterprise applications.

What Java EE Was Designed to Do

Enterprise applications often need to handle many users, protect sensitive information, connect to databases, and coordinate work across multiple systems. Building each of these capabilities from scratch can be complex. Java EE specifications defined standard ways for applications to address these requirements.

Rather than prescribing one specific product, the platform described APIs and behaviors that compatible application servers could implement. This gave organizations a choice of vendors and helped applications move between compliant environments with fewer changes.

Key Technologies

Java EE included a broad collection of technologies. The exact set evolved over time, but several became especially well known:

• Servlets and JavaServer Pages (JSP): Technologies for handling web requests and generating dynamic web content. Newer Java EE releases also included JavaServer Faces (JSF) for component-based user interfaces.
• Enterprise JavaBeans (EJB): A component model for business logic, with services such as transactions and security provided by the runtime.
• Java Persistence API (JPA): A standard for mapping Java objects to relational database data.
• Java Message Service (JMS): An API for sending messages between application components and systems.
• Java API for RESTful Web Services (JAX-RS): A standard for building HTTP-based REST services.
• Bean Validation: A way to define and check constraints on application data.
• Dependency injection and contexts: Facilities for managing components and their dependencies, including Contexts and Dependency Injection (CDI).

These technologies were designed to work together, though developers could use only the parts their applications needed.

Application Servers and Containers

Java EE applications typically run inside an application server, also called a runtime or container. The server provides services such as component management, security, database connection pooling, and transaction coordination. Examples of Java EE application servers included GlassFish, WildFly, and commercial products from several vendors.

This approach can reduce the amount of infrastructure code an application team must maintain. It also introduces a runtime that must be configured, operated, and kept up to date. Some applications use only a small portion of the platform, while others rely on a larger set of server-managed services.

From Java EE to Jakarta EE

Java EE was developed under Oracle’s stewardship. In 2017, Oracle transferred the enterprise Java technologies to the Eclipse Foundation. The platform was renamed Jakarta EE, and the Eclipse Foundation now manages its specifications and community processes.

The transition also involved a change in package names. Older Java EE APIs commonly used packages beginning with javax. Jakarta EE 9 introduced the new jakarta namespace for the platform APIs. As a result, moving an application to a newer Jakarta EE version may require source-code changes, updated dependencies, and a compatible application server.

Java EE documentation and applications remain relevant, especially in organizations maintaining established systems. For new development, Jakarta EE is the current continuation of the platform.

Java EE and Modern Application Development

Enterprise Java has changed over time. Modern Jakarta EE runtimes can support cloud deployments, containers, and microservices, while retaining standard APIs familiar to many Java developers. Frameworks such as Spring offer another widely used approach to building Java applications, with their own programming model and ecosystem.

The best fit depends on the project. Teams may consider existing skills, application-server requirements, deployment targets, vendor support, and the specific APIs a system needs. Standards can be valuable when portability and a shared specification matter; frameworks may be attractive when a team prefers a more integrated or opinionated development experience.

Benefits and Considerations

Java EE’s standards-based approach offers several potential benefits:

• Portability: Applications built against standard APIs can often be deployed on compatible runtimes with less vendor-specific code.
• Built-in services: The runtime can handle common concerns such as transactions, security, and resource management.
• A mature ecosystem: Enterprise Java has a long history, extensive documentation, and a large community of developers and vendors.
• Consistency: Standard APIs give teams a shared vocabulary and predictable programming interfaces.

There are also considerations. Application servers can add operational complexity, and platform versions, server support, and library compatibility need to be managed carefully. The move from javax to jakarta can also make upgrades more involved for older applications.

Conclusion

Java Enterprise Edition established a standards-based foundation for building business applications with Java. Although the platform is now known as Jakarta EE, its core ideas—portable APIs, managed runtime services, and support for large-scale applications—continue to shape enterprise Java development. Understanding Java EE is useful not only for maintaining legacy systems, but also for understanding the history and direction of the modern Jakarta EE platform.

 

Understanding Java Enterprise Edition (Java EE): Key FAQs and Insights

1. What is Java Enterprise Edition (Java EE)?
2. What is the difference between Java EE and Jakarta EE?
3. What are the main features of Java EE?
4. What technologies and APIs are included in Java EE?
5. What is a Java EE application server?
6. How is Java EE different from Java SE?
7. Is Java EE still used for enterprise application development?
8. How do I get started building a Java EE or Jakarta EE application?

What is Java Enterprise Edition (Java EE)?

Java Enterprise Edition (Java EE) was a collection of standards and APIs for building large-scale business applications with Java. It provided tools for common needs such as web development, database access, security, messaging, and transaction management, typically through an application server. Java EE is now known as Jakarta EE, which continues the platform under the Eclipse Foundation.

What is the difference between Java EE and Jakarta EE?

Java EE and Jakarta EE are successive names for the same enterprise Java platform. Java EE was originally developed under Oracle; after Oracle transferred it to the Eclipse Foundation, the platform was renamed Jakarta EE. The specifications and APIs continue to evolve under the new name, but there is an important compatibility change: Jakarta EE 9 moved many API packages from javax.* to jakarta.*. As a result, older Java EE applications may need code and dependency updates to run on newer Jakarta EE versions.

What are the main features of Java EE?

Java EE’s main features include standardized APIs for building web applications, managing business logic, connecting to databases, sending messages, and creating RESTful services. It also provides services such as dependency injection, security, transaction management, and component management through an application server. Together, these features help developers build scalable, reliable enterprise applications while reducing the need to implement common infrastructure from scratch. Java EE is now known as Jakarta EE, its ongoing successor.

What technologies and APIs are included in Java EE?

Java EE includes standardized technologies and APIs for building enterprise applications, including Servlets and JavaServer Pages (JSP) for web development, Java Persistence API (JPA) for database access, Enterprise JavaBeans (EJB) for business logic, Java Message Service (JMS) for messaging, JAX-RS for RESTful web services, and CDI for dependency injection. It also provides APIs for security, transactions, validation, and other common application needs. The exact set varies by Java EE version; the platform’s current continuation is Jakarta EE.

What is a Java EE application server?

A Java EE application server is a software platform that runs Java EE applications and provides services they commonly need, such as security, database connections, transaction management, and web request handling. It manages application components within a runtime environment, so developers can rely on standardized services instead of building every feature from scratch. Java EE is now known as Jakarta EE, and compatible application servers provide the runtime for Jakarta EE applications as well.

How is Java EE different from Java SE?

Java SE (Standard Edition) provides the core Java language, libraries, and runtime features used to build general-purpose applications. Java EE (Enterprise Edition), now continued as Jakarta EE, builds on Java SE by adding standardized APIs and services for enterprise applications, such as web services, database persistence, messaging, security, and transaction management. In short, Java SE is the foundation, while Java EE is designed to support larger, server-based applications that often run in an application server.

Is Java EE still used for enterprise application development?

Yes, Java EE is still used to develop and maintain enterprise applications, especially in organizations with established systems built on the platform. Java EE has evolved into Jakarta EE, which continues to provide standards for building Java applications, including APIs for web services, persistence, security, and transactions. Teams starting new projects may choose Jakarta EE or other Java frameworks based on their requirements, existing expertise, and deployment environment.

How do I get started building a Java EE or Jakarta EE application?

To get started, install a supported JDK and choose a Jakarta EE–compatible runtime, such as Payara, WildFly, or Open Liberty. Create a project with Maven or Gradle, using dependencies that match your runtime’s Jakarta EE version, then begin with a small feature such as a REST endpoint using Jakarta REST. Run the application locally, test it, and deploy it to your chosen runtime. If you’re working with an older Java EE application, check its API and server versions before upgrading, since newer Jakarta EE releases use the jakarta package namespace instead of javax.