I can't speak for Java/Python development but I do a lot of JavaScript in Cloud9. Its a cloud IDE that got purchased by AWS. Pretty smooth setup and if you're already in AWS already you can take some advantage of existing services that hookup to Cloud9.
Are you subscribing to cloud 9 or is it part of your company's toolchain?
I have tried codenvy and codeanywhere. Had lot of trouble get going. Most of the times I see tons of error messages in the js console. Thanks for suggesting me this article.