Any way to get the total count of input data set

My use case is to enable my step able to report the percentage of completion on each commit. To achieve that, I need count the total size of input data set (e.g. the no. of line in a file).

To my understanding, it has no out-of-the-box way to do the titled thing in SB. Please correct me if don't.

If I want to implement such thing what, I think think of some of the following plug-in point to calculate the total item count:

- at StepExecution.beforeStep
- at Reader

which one is better or any comments on these? Or any new direction for doing this?

It's a bit of a tough problem. The only way that wouldn't require you to read through the whole file once to determine a line count would be to use the size in bytes. If you have fixed length input, it would be easy, since you know exactly how many bytes are in a line, multiplying the current line count by that number and dividing by the total size would give you the percentage. I have no good ideas on how to do the same with delimited input though. I suppose we could use the number of bytes read instead of lines read in the reader, which could help with that.

Thanks for your reply.

I think we can divide the problem into where and how. I think you have suggested some ways for 'how'. How about where?

- at StepExecution.beforeStep?
- at Reader?