Class JavaLaunchHelper is implemented in two places

Question

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

Answer 1

Since “this message is harmless”(see the @CrazyCoder's answer), a simple and safe workaround is that you can fold this buzzing message in console by IntelliJ IDEA settings:

1. 【Preferences】- 【Editor】-【General】-【Console】- 【Fold console lines that contain】
   Of course, you can use 【Find Action...】(cmd+shift+A on mac) and type Fold console lines that contain so as to navigate more effectively.
2. add Class JavaLaunchHelper is implemented in both

On my computer, It turns out: (LGTM :b )

And you can unfold the message to check it again:

PS:

As of October 2017, this issue is now resolved in jdk1.9/jdk1.8.152/jdk1.7.161
for more info, see the @muttonUp's answer)