Camera Plugin issue with class BuildHelper

i want to use camera feature for my mobile app
when i include the plugin

1. ionic plugin add cordova-plugin-camera

after done, then i start compiling my app.
and it give me error

Error:(32, 26) error: cannot find symbol class BuildHelper
Error:(140, 39) error: cannot find symbol variable BuildHelper

Error:Execution failed for task ':compileDebugJavaWithJavac'.
> Compilation failed; see the compiler error output for details.

any help ?