Well 2 thing stand out for me from links you mentioned:

> The applications use a combination of Thales proprietary middleware written in C combined with Java code enabled by the Java™ Native Interface (JNI).

> AONIX has additionally delivered professional services to help PERC Ultra users at Thales optimize their applications and improve execution performance including, a customer-specific training course handled the needs of coding in Java™ with hard real time constraints.

Seems like with helping of C and Consulting on 'How to do Java right' they made it work.

> End-to-end distributed thread timing constraints measured from stimulus to response are typically under 100 ms.

Since it is slightly faster than typical (per char) typing speed on keyboard. It appears nice but terribly impressive real time Java use case.

For me it is impressive, because if the system doesn't work, the wrong guys die.