osx vs code java outline no symbol found

details:

outline section is empty, although the plugin of java language support by redhat been already installed.

problem:  JDK

fix:

uninstall the plugin

uninstall any other java plugins

restart vs code and quit

download JDK 1.8 from oracle, install it. 

restart computer

launch vs code

install java extension package

install java support by red hat

restart vs code

(working now)  :)