Today I upgraded my Intellij Idea on macOS Sierra, and now, when I run apps in console I have this error:
objc[3648]: Class JavaLaunchHelper is implemente
This happened to me when I installed Intellij IDEA 2017, go to menu Preferences -> Build, Execution, Deployment -> Debugger and disable the option: "Force Classic VM for JDK 1.3.x and earlier". This works to me.