Java doesn't need to have a non-deterministic GC. The Real-Time Specification for Java [1] has resulted in a number of JVM implementations designed for low-power, embedded devices; these implementations use a deterministic GC to provide hard real-time guarantees, and the devices they run on are less powerful than the game consoles from even a couple of generations back.

[1]: http://en.wikipedia.org/wiki/Real_time_Java