[OAK-4472] Decouple SegmentReader from Revisions

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: Segment Tar 0.0.2, 1.6.0
• Component/s: segment-tar
• Labels: technical_debt
• Assignee: Michael Dürig
• Reporter: Michael Dürig
• Created: 15/Jun/16 10:31
• Updated: 27/Jun/16 08:21
• Resolved: 15/Jun/16 10:33

Description

The SegmentReader.readHeadState() introduces a de-facto dependency to Revisions as access to the latter is required for obtaining the record id of the head.

To decouple SegmentReader from Revisions I propose to replace SegmentReader.readHeadState() with SegmentReader.readHeadState(Revisions revisions). As this results in a lot of boilerplate for callers (i.e. fileStore.getReader().getHeadState(fileStore.getRevisions())), we should also introduce a convenience method FileStore.getHead() clients could use to that matter.