Java Real-time debugging (gaming)

Question

In this video :http://www.youtube.com/watch?v=BES9EKK4Aw4

Notch (minecraft's creator) is doing what he refers to as 'real-time debugging'. He's actually modifying the code and plays with the game at the same time without recompiling everytime.

Does anyone know what this is called or where I could get more information on how to achieve this? I've been looking around without any success!

Regards, Erwald

Answer 1

This feature is called "hotswapping" and is supported by certain JVMs. The Eclipse IDE debugger is capable of hot-swapping your code in the debug (F11) mode. Eclipse can also auto-build your project once you save a modified file (AND hot-swap when running a debug build). Notch seems to be using exactly this technique.

Answer 2

some IDE s are doing this ie: eclipse, netbeans, intellij idea etc.

however some changes requires recompiling (method addition or deletion etc.)

and what he using is probably eclipse.