So in Windows in the comand line I wrote
set GRADLE_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,address=9999,server=y,suspend=y
Then I get:
C:\Project>gradle main
Listening for transport dt_socket at address: 9999
Then I put a breakpoint in the gradle.build file

and at last from Eclipse IDE

And I get

why this happend? So I can't debug gradle files, I can only debug java,groovy.. files?