Jakarta Commons Cookbook in Japanese

I got my copy of the Japanese translation of Jakarta Commons Cookbook today, and it’s an interesting read if you can read Kanji (is it Kanji even?) I don’t know. The interesting thing about having a copy of a book you wrote in Japanese is that you can read it. I can say the same about the German translation of Maven: A Developer’s Notebook.

All the copy is in Japanese, but class names and variable names are still in English. The questions I have about this are: Do Japanese programmers program in English? And by that I mean, do they use the same language keywords I use? And, when they write variable names do they do so in English?