Support new "generations" of existing segments #1
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…untouched partitions.
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| @SuppressWarnings("unchecked") | ||
| private VersionType getSourceVersion(VersionType version) { | ||
| if (version instanceof String) { |
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When could VersionType be something other that String?
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Currently it is always String in practice, but it would not be nice to add implicit type constraints to the previous functionality of this class.
| VersionType sourceVersion = getSourceVersion(entry.getValue().getVersion()); | ||
| TimelineEntry sourceEntry = sourceVersion != null ? versionEntry.get(sourceVersion) : null; | ||
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| if (sourceEntry != null) { |
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Add some comments on what's happening here and why?
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Added. Also added the main description of the PR to SegmentGenerationUtils class documentation.
| // For each timeline entry, add partitions from the source version that do not exist for the existing timeline | ||
| // object. These are added as a separate entry to the list. | ||
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| for (int i = 0; i < initialSize; i++) { |
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Why not use the : iteration here? It looks like i is not used for any purpose other than holders.get(i), unless I fail to find it.
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The same list is being added to in this loop, only the original items should be iterated.
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Add this as a code comment, before someone will replace this.
| segments | ||
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| dbSegments.close(); |
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Should that be in a finally block, or could you use try-with-resources?
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Using try-with-resources now.
A segment with version containing
_gen_is considered to be a new generation of an existing segment, and the version it is generated from (source version) matches the part before_gen_.A generated segment has the following properties:
Additionally changed the default ordering of numbered partitions - the partition number now has a higher priority in comparisons than the core partition count. Before, if you had segments with
(partitionNumber, corePartitionCount)of(0, 2), (1, 2), (2,0), this would not have been considered a complete set of partitions since they were sorted to and verified in the order(2,0), (0, 2), (1, 2).