TIL: The JVM can ommit stacktraces in the name of optimization

While investigating an issue, I saw a NullPointerException without a stacktrace..

ERROR logs that omits the throwable object (and it is available) is quite devastating. I call such situation 'swallowing the exception'.

However, this time, it is very different. Apparently the HotSpot JVM may opt to not log the stacktrace but  only the exception:

source: https://stackoverflow.com/questions/2411487/nullpointerexception-in-java-with-no-stacktrace

Having a look at older instances of this ERROR log, I found that the occurrence the day before indeed had stacktrace. This is quite surprising and something I would not expect..