How to test MobileFirst Adapter API outside of application

I am going through the tutorials of IBM MobileFirst. I have created an android application in MobileFirst and uploaded the Java HelloWorld adapter.

I can successfully trigger the API (such as the greet function) through my android app and I get back the desired result. But I would like to test the API also in the Browser, or through curl or through postman... But whenever I use the Browser or curl or Postman with:

http://localhost:XXXPORTXXX/mfp/api/adapters/SampleAdapter/resource/greet?name=myname

I dont get any string back... the browser stays empty and curl does not write anything...