Cucumber has built in option to generate json type of report.
this is not for human brain consumption.
this is to be used by third party tools 
so that we can generate better test reports. 
better than the default HTML Report coming from cucumber.
-> to open the json file: 1- Add plugin: "json:target/cucumber.json", 
2- RUN cukes runner. 3- json file will be created by cucumber. 
4- if you want to open, you can doubleclick and open the file. 
(but you don't have to)