Yaolong Liu

Thanks Reply, My understanding is that, we can implement the `SampleNameFilter` , and then call `collect(Predicate sampleNameFilter)` to bypass this bug explictly, I implemented the code logic, please help me...

I think I probably understood your idea, but there may be a difference. We can't rewrite `collect(Predicate sampleNameFilter)`, because the situation of reporting a null pointer exception requires a method...

Sorry for the late reply, This is indeed a solution to the problem, but if we do not know in advance which metric cause a null pointer exception, using this...

So, do you think we can throw exception information directly in the `collect` method?

@dhoard Thanks for reviewing the code and making suggestions, I'll try to fix this again based on your suggestion

@maobaolong @jiacheliu3 @dbw9580 Could you help take a look at the pull request, thanks in advance!

@jiacheliu3 Thanks a lot for reviewing the pull request! PTAL