[GORA-225] Various Issues with MemStore

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.3
• Fix Version/s: 0.9
• Component/s: gora-core, testing
• Labels: gsoc2015
• Environment: Nutch 2.x HEAD, gora-core 0.3
• Assignee: Kevin Ratnasekera
• Reporter: Lewis John McGibbney
• Created: 18/May/13 21:00
• Updated: 03/May/19 09:17
• Resolved: 13/Mar/19 19:11

Description

In Nutch we have numerous testing scenarios which simulate persistence of data to Gora in some form or other. It has worked good as until now.
Now that gora-sql-0.1.1-incubating artifact is non-compatible with gora-core 0.3, there is a requirement to address this situation in order to keep some degree of integrity within the Nutch codebase.
Specifcally a number of tests [0][1][2][3] all extend a Util testing class which utilizes functionality from the gora-sql artifact.

My initial solution was to switch to using MemStore... which brought me to logging this issue!

I've logged sub issues here to make clear distinction about my observations.

Issue Links

• relates to: NUTCH-1572 Nutch 2.x should use o.a.g.mem.store.MemStore for testing

Sub-Tasks

• java.util.NoSuchElementException when attempting to obtain TreeMap.firstKey in MemStore#execute: Resolved
• Failing assertions when putting and getting Values using MemStore#execute: Resolved
• java.util.ConcurrentModificationException when using MemStore for concurrent tests: Resolved
• java.util.NoSuchElementException thrown by accessing java.util.concurrent.ConcurrentSkipListMap.firstKey in MemStore: Resolved
• Fix NPE within MemStoreTest.testMemStoreDeleteByQueryFields and failed assertion within MemStoreTest.testGetWithFields: Resolved