This is a sample app that I'm using for demos and PoCs.
git clone https://github.com/eduardorj/webapp-java-springboot.git
If you use Maven, you can run the application by using ./mvnw spring-boot:run. Alternatively, you can build the JAR file with ./mvnw clean package and then run the JAR file, as follows:
java -jar demo-0.0.1-SNAPSHOT.jar