Added an api to accept block of code and to return result and time taken to execute.

[FuncGuy]

Hi,
@kluever @kevinb9n @ogregoire
I've added an API to accept block of code and return result and time taken to execute. #3535

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[FuncGuy]

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[kluever]

I think we (also) probably want an API that only returns the elapsed Duration, where the result of the method invocation can be ignored or is void.

[ogregoire]

I don't like how the exceptions are handled.

We do not know if there was an exception or not. There is currently no difference between an exception thrown by the measured code block and an exception being returned by the same code block.

I don't know what the people would prefer: let the exception pass through and get no result of a timed stopwatch, or on the contrary measure the code block and get the caught exception in a specific returned value.

So I'd say this would require more API:

• measure -> Duration (ignore result, and let the exception through)
• measureAndGet -> TimedResult (get the result, but let the exception through)
• measureAndCatch? -> ExceptionallyTimedResult? (get the result, catch the exception, measure anyways)

Anyways, this should probably be better refined.

[FuncGuy]

@kluever @ogregoire
I've addressed the review comments by @ogregoire if any further change is needed please mention it.

[netdpb]

Looks relevant to #3528.

[rahilsh]

why an empty method, () -> update() can be replaced with () -> {}