The same as the simplest hello world example but this time the hello world server is in a verticle.
Right click the HelloWorld class and run as main class.
Now point your browser at http://localhost:8080
Build it into a fat, executable jar with:
mvn install
Run it with
java -jar target/apex-example-verticle-3.0.0-SNAPSHOT-fat.jar
Now point your browser at http://localhost:8080
As it's a verticle you can use any of the command line options for deploying verticles, e.g. to increase the number of instances:
java -jar target/apex-example-verticle-3.0.0-SNAPSHOT-fat.jar -instances 8
This makes it easy to scale your services across available cores without having to write the code to manually instantiate more servers yourself.