Jakarta EE and Java EE 8 in Liberty
Liberty supports the full Java™ Platform, Enterprise Edition (Java EE) 8, which provides a number of improvements over previous Java EE versions.
WebSphere® Application Server Liberty supports the Jakarta EE Platform (Jakarta EE) 9.1.
Benefits of Jakarta EE
Jakarta EE offers a community-driven open source model with more frequent releases than Java EE, enabling it to evolve more quickly to address the needs of modern applications.
The Jakarta EE 8 full platform and Web Profile technologies are based on Java EE 8 technologies. The Jakarta EE 8 specifications are compatible with Java EE 8 specifications.
For more information about Jakarta EE in Liberty, see the Open Liberty guides on Jakarta EE technologies.
Jakarta EE 9.1 full platform and web profile
technologies support the Jakarta EE 9.1 specifications. Due to changes in the underlying API package
names between Jakarta EE 8 and Jakarta 9.1,Liberty features that support Jakarta EE 9.1 are
incremented to new version numbers and in some cases have new short names. If you are moving
applications from Java EE or a previous version of Jakarta EE to Jakarta EE9.1, you might need to
update feature versions or short names in your
server.xml file. For more
information, see Jakarta EE 9.1 feature updates on the Open Liberty
Benefits of Java EE 8
- The JSON-P specification adds support for the JSON Pointer and JSON Patch standards in JSON-P 1.1 (JSR-374).
- The new Security API (JSR 375) defines self-contained security applications that are portable across application servers. These security applications can provide their own implementations to over-ride authentication mechanisms or identity stores.
- The servlet API adds support for HTTP 2.0 in Servlet 4.0 (JSR 369).
- The JAX-RS specification adds support for a reactive client, server sent events, out of the box @PATCH method support, the option to specify the executor service, and out of the box JSON-B support. These additions are available in JAX-RS 2.1 (JSR 370).
- Bean Validation 2.0 (JSR 380) provides an annotation-based model for validating JavaBeans. You can use the specification to assert and maintain the integrity of data as it travels through an application.
- Contexts and Dependency Injection (CDI) 2.0 (JSR 365) adds support for firing asynchronous events, ordering event observers, using configuration SPIs, using built in annotation literals, and applying interceptors on producers.
- Deprecation of older technologies
The following older technologies are optional for Java EE 8: For EJB 3.2 (JSR-345), EJB entity beans and EJB QL that goes with it; JAX-RPC 1.1 (JSR-101); JAXR 1.0 (JSR-93); Java EE Deployment 1.2 (JSR-88).
Java EE 8 full platform and Web Profile
The Java EE 8 specification defines the full platform Enterprise Edition. The Web Profile is a properly defined subset of the full platform.
- Web Profile
- The Web Profile defines a reasonably complete stack that targets "modern" web applications. This stack is a subset of the full platform standard APIs, capable of addressing the needs of most web applications.
- Full platform
- The full platform defines the full complement of the Java EE programming model. Besides the Web Profile features, the full platform has specifications for advanced business capabilities that an enterprise needs, such as for connectivity, enterprise beans, messaging, and application clients.
You need to consider these definitions when you install Liberty and its available features. Installation options provide the Liberty runtime (kernel) and features that support the full platform or Web Profile. You can choose to install the Liberty kernel with just the Web Profile features or install individual Java EE features to your existing Liberty kernel installation.
You also need to consider the definitions when you deploy applications to a Liberty server. For example, if your Liberty installation supports Web Profile features but your application needs a server that supports enterprise connectivity APIs, you must add full platform features to your Liberty installation or deploy the application to a Liberty installation that has full platform features.
To quickly add support for Java EE to your Liberty server, use either the
javaee-8.0 convenience features in the feature
manager of your server configuration; for example:
<featureManager> <feature>javaee-8.0</feature> </featureManager>
A third convenience feature,
javaeeClient-8.0, is also available to quickly
configure an application client component:
<featureManager> <feature>javaeeClient-8.0</feature> </featureManager>
Installing a Liberty kernel with Java EE 8 features
The quickest way to install a Liberty runtime with Java EE 8 features is to download a compressed (.zip) file from the Open Liberty download and extract the file into an empty directory. See Installing Liberty using downloaded archives.
You also can install a Liberty runtime with Java EE 8 features by using a developer tool such as WebSphere Application Server Developer Tools for Eclipse. See Installing Liberty Repository assets.
You can add Java EE 8 features to an existing installation by running the featureManager or installUtility command. See Installing Liberty Repository assets.