Demo project for the talk "Pimp your Jakarta EE application"

Starting point

This project builds a small JEE application composed of a REST api, some (CDI) injected services and a JPA based persistence layer.

You can build the application with

mvn package

and deploy it in some Java EE 8 application server, e. g. WildFly 26.

The server must offer a datasource with jdbc/showcase as JNDI name. You may use the WildFly CLI script src/main/wildfly/showcase-ds.cli for adding a matching datasource to your server configuration, but you have to install a driver module for PostgreSQL first (see server documentation).

For demo purposes there is a compose file in src/main/docker-compose/postgres for starting a PostgreSQL server at localhost:5432.

The small REST api includes an endpoint for retrieving all Person objects from the database:

curl localhost:8080/api/persons

The db will be populated with a few test entries upon the first request.

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Migrate from Java EE 8 to Jakarta EE 10

For upgrading the application from JEE 8 to JEE 10, the pom.xml includes a configuration of the OpenRewrite plugin. For clarity in this demo it has been placed into a Maven profile. Run it by

mvn -PtoJakarta rewrite:run

You have to adjust pom.xml afterwards - please see the comment on top of the profile definition.

You may now deploy the application in an Jakarta EE 10 server, e. g. WildFly 27.

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Use WildFly as "Jar" Server Runtime

WildFly can be provisioned as bootable jar by means of the WildFly JAR Maven Plugin. For clarity in this demo it has been placed into a Maven profile. Use

mvn -Pwildfly package

to download, customize and preconfigure a WildFly server into target/wildfly-bootable.jar consisting of layers for REST, CDI, JPA and H2 as default datasource. The combined application and server can be started with

java -jar target/wildfly-bootable.jar --deployment=target/pimp-jee.war

This is using a hollow jar, i. e. the server jar contains just the server part and not the deployment. You can build a fat jar containing both by configuring the plugin with <hollow-jar>false</hollow-jar>.

The plugin offers a development mode with hot reloading changes:

mvn -Pwildfly wildfly-jar:dev-watch

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Use Quarkus as "Micro" Server Runtime

Standard JEE sources can be used with Quarkus to build an optimized server application. For clarity in this demo it has been placed into a Maven profile. Use

mvn -Pquarkus package

to build and package the application as jar file with dependencies in target/quarkus-app. The application can be started with

java -jar target/quarkus-app/quarkus-run.jar

The plugin offers a development mode with hot reloading changes:

mvn -Pquarkus quarkus:dev