Well this is basically for frontend and they are likely to hire people who knew javascript and react or angular frameworks but in the jd it was written that proficiency in any language is fine but no I guess he was looking for javascript and react because the people who interviewed with me some were from Java, python and javaScript and he had asked theory or same concept to people who had javascript as their language so ya but in the interview he just asked to introduce yourself and then he asked about my projects and if I had them up on github or not so ya this is all he didn't ask me any questions related to Java( my language).