NIFI-15904 Fix Lineage Start Index in Session.create()

[exceptionfactory]

Summary

NIFI-15904 Corrects the value of Lineage Start Index on FlowFiles created using the StandardProcessSession.create() method, setting the value using the number provided as the FlowFile ID from the FlowFile Repository. Using the FlowFile ID avoids introducing a separate variable for tracking the index, while providing an increasing number.

Other create() methods set the Lineage Start Index from parent FlowFiles, but the current implementation always uses the default value of 0, leading the potential ambiguity when the framework creates multiple FlowFiles with the same Lineage Start Date.

The changes include a new unit test method to check the expected value of the Lineage Start Index.

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  • JDK 21
  • JDK 25

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[markap14]

Thanks for fixing @exceptionfactory! Logic seems reasonable to me. Ensure that we have a monotonically increasing index for a given timestamp (and beyond). +1 happy to merge pending Github Actions completing successfully.