malformed URL Exception no protocol - swagger

http://abcd/api/main.json, I am using the above mentioned json url. Its loading properly in the web browser, but when I try to create soap file using Add swagger in soap ui, its throwing me 'malformed URL Exception no protocol' error. Could you please let me know the issue.

I am using SOAP UI and I followed the steps mentioned in url http://olensmar.blogspot.in/2013/05/soa ... -true.html and http://olensmar.blogspot.in/2012/12/tes ... roovy.html
URL to add swagger