GlassFish

GlassFish is an open-source application server for the Java Platform, Enterprise Edition (Java EE), now aligned with Jakarta EE. It provides a runtime environment for deploying and managing enterprise Java applications, including components such as servlets, EJBs, JPA, and JMS. GlassFish includes a management console and command-line tooling for configuration, deployment, monitoring, and lifecycle management. It is designed to serve as the reference implementation of the Java EE specifications.

GlassFish originated as an open-source project from Sun Microsystems to demonstrate and implement Java EE. After Oracle acquired Sun in 2010, Oracle continued development with GlassFish 3 and 4. In 2016–2017 Oracle donated the governance of the project to the Eclipse Foundation, where it was rebranded as Eclipse GlassFish to act as the reference implementation for Jakarta EE.

Technically, GlassFish is built around modular components and the HK2 dependency injection framework, with support for the full Java EE stack and related technologies such as CDI, JPA, JAX-RS, and JMS. It includes a web-based administration console, a scripting interface (asadmin), and features for clustering and high availability. The server integrates with typical Java EE runtimes and can be used for development, testing, and production deployments.

Licensing for GlassFish is open source under a dual license model (CDDL and GPL with Classpath Exception). The Eclipse GlassFish project continues to be maintained by a community of developers and organizations, providing updated implementations aligned with Jakarta EE specifications. GlassFish remains a widely used reference server for developers seeking standards-compliant runtime environments.