In eXo Platform, you can use IDE to develop a REST service online without building the whole project. In this case, the REST service will be written in Groovy (whose syntax is mostly compatible to Java).
Go to → to open the IDE application.
Select→ → . The default template of a Groovy file will be shown. Here, you can customize this file to your desire.
Save the file, then click→ from the top menu of IDE.
Go to http://mycompany.com:8080/rest/my-service/helloworld/eXo. The output ("Hello eXo" in this scenario) will be shown.
To get the REST service URL, simply select→ → .
See Managing REST Service of IDE User Guide for all actions of REST service in IDE.