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> Exceptions for Control Flow

This one is so prevalent that JVM has an optimization where it gives up on filling stack for exception, if it was thrown over and over in exact same place.

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Author here. Great callout. That's the -XX:+OmitStackTraceInFastThrow optimization, been around since JDK 5. The C2 compiler detects exceptions thrown repeatedly from the same site and starts reusing a preallocated instance without filling the stack trace. Good for performance, but it makes debugging harder in production since you lose the trace. You can disable it with -XX:-OmitStackTraceInFastThrow if you need the traces back.

ah, thank you. Haven't worked in java for a bit now, but that was the only one I read where I was like "I'm sure we didn't have to avoid this when I worked on java".

The rest were all very familiar. Well, apart from the new stuff. I think most of my code was running in java 6...

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