I've been using
IntelliJ IDEA by JetBrains for the past 11 years professionally, and the past 3 years for First. It beautifully handles Java, Python, Scala, Groovy, Clojure, and many more languages & frameowrks. This year I'm hoping to get an FRC plug-in written for it so that others can use it easily for FRC work. But I need to wait until I see the changes for the new year with the new controller.
For a C/C++ IDE, take a look at JetBrians new
CLion IDE. It's still in Beta, but very slick nonetheless.