This is a basic REST API starter kit using Apache Camel and Spark. Running the HelloWorld application will launch an embedded Jetty server that will listen on http://localhost:9091 for 10 minutes. The following REST endpoints are defined by default and can be used as examples:
http://localhost:9091/api/v1/register
http://localhost:9091/api/v1/customers/{id}
http://localhost:9091/api/v1/customers/{id}/orders
Full walkthrough can be found here: https://blockchainhero.com/?p=266