It is currently in use by another Gradle instance

Question

I\'m new to Gradle build system. I want to do some basic functions on it. I\'m running/building it in command line. I am referring User guide. And, doing some simple tasks.<

Answer 1

Have tried all this answers, including kill java process, delete .gradle in HOME_DIR and in project dir, restarted Android Studio, and even restarted OS.

It started to work normally only after I launched gradle sync.