https://github.com/antlr/jetbrains-plugin-sample

https://medium.com/@shan1024/custom-language-plugin-development-for-intellij-idea-part-03-2bfcc7f1517

Thank you for reference, but jetbrains-plugin-sample doesn't explain how lexer, parser and PSI files generated. Can you pls help with the tutorial to implement ANTLR Parser and Lexer and PSI files. Basically I am looking for help in development of these files.

Yann, Can you please help me with documentation of jetbrains-plugin-sample.

We do not officially support ANTLR-based custom languages, sorry.