Problem " cordova build " after add "cordova-plugin-googleplus"

hello dear friends
i have an ionic3 framework app.
i had no problem until i installed googleplus-plugin. after that when run "cordova build " i get this error.
can any one please help me

Error: cmd: Command failed with exit code 1 Error output:
FAILURE: Build failed with an exception.

* What went wrong:
A problem occurred configuring root project 'android'.
> Could not resolve all dependencies for configuration ':_debugCompile'.
   > Could not resolve
     Required by:
      > Could not resolve
         > Failed to list versions for
            > Unable to load Maven meta-data from
               > Could not GET ''.
                  > Connect to [] failed: Connection timed out: connect

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

Seems you can’t connect to that URL.
I can but get a 404, so I am not sure why this is relevant…

Proxy or something like that?

thank you dear Sujan12

yes i am sure there is no proxy which prevent access to net on my system.
i don’t know what is wrong but i have this problem in some plugin such as googleplus and x-socialsharing …
i think there is some thing wrong with android sdk or i don’t know some thing like that