I had a professor that was adamant Java IDEs are not written in Java. I pointed out IntelliJ was written in Java, but he countered that it used native code unde

I had a professor that was adamant Java IDEs are not written in Java. I pointed out IntelliJ was written in Java, but he countered that it used native code under the hood to do the UI. I never investigated this claim any further, and don't have a strong feeling as to whether it is true or not.