发布于 2015-06-03 01:47:29 | 237 次阅读 | 评论: 0 | 来源: 网友投递
Apache Lucene全文检索引擎工具包
Lucene是apache软件基金会4 jakarta项目组的一个子项目，是一个开放源代码的全文检索引擎工具包，即它不是一个完整的全文检索引擎，而是一个全文检索引擎的架构，提供了完整的查询引擎和索引引擎，部分文本分析引擎（英文与德文两种西方语言）。Lucene的目的是为软件开发人员提供一个简单易用的工具包，以方便的在目标系统中实现全文检索的功能，或者是以此为基础建立起完整的全文检索引擎。
Lucene 5.1.0 发布，此版本现已提供在：http://www.apache.org/dyn/closer.cgi/lucene/java/5.1.0。
更新内容如下：
新特性 (9)
LUCENE-6066: Added DiversifiedTopDocsCollector to misc for collecting no more than a given number of results under a choice of key. Introduces new remove method to core's PriorityQueue.
(Mark Harwood)
LUCENE-6191: New spatial 2D heatmap faceting for PrefixTreeStrategy.
(David Smiley)
LUCENE-6227: Added BooleanClause.Occur.FILTER to filter documents without participating in scoring (on the contrary to MUST).
(Adrien Grand)
LUCENE-6294: Added oal.search.CollectorManager to allow for parallelization of the document collection process on IndexSearcher.
(Adrien Grand)
LUCENE-6303: Added filter caching baked into IndexSearcher, disabled by default.
(Adrien Grand)
LUCENE-6304: Added a new MatchNoDocsQuery that matches no documents.
(Lee Hinman via Adrien Grand)
LUCENE-6341: Add a -fast option to CheckIndex.
(Robert Muir)
LUCENE-6355: IndexWriter's infoStream now also logs time to write FieldInfos during merge
(Lee Hinman via Mike McCandless)
LUCENE-6339: Added Near-real time Document Suggester via custom postings format
(Areek Zillur, Mike McCandless, Simon Willnauer)
Bug 修复 (10)
LUCENE-6368: FST.save can truncate output (BufferedOutputStream may be closed after the underlying stream).
(Ippei Matsushima via Dawid Weiss)
LUCENE-6249: StandardQueryParser doesn't support pure negative clauses.
(Dawid Weiss)
LUCENE-6190: Spatial pointsOnly flag on PrefixTreeStrategy shouldn't switch all predicates to Intersects.
(David Smiley)
LUCENE-6242: Ram usage estimation was incorrect for SparseFixedBitSet when object alignment was different from 8.
(Uwe Schindler, Adrien Grand)
LUCENE-6293: Fixed TimSorter bug.
(Adrien Grand)
LUCENE-6001: DrillSideways hits NullPointerException for certain BooleanQuery searches.
(Dragan Jotannovic, jane chang via Mike McCandless)
LUCENE-6311: Fix NIOFSDirectory and SimpleFSDirectory so that the toString method of IndexInputs confess when they are from a compound file.
(Robert Muir, Mike McCandless)
LUCENE-6381: Add defensive wait time limit in DocumentsWriterStallControl to prevent hangs during indexing if we miss a .notify/All somewhere
(Mike McCandless)
LUCENE-6386: Correct IndexWriter.forceMerge documentation to state that up to 3X (X = current index size) spare disk space may be needed to complete forceMerge(1).
(Robert Muir, Shai Erera, Mike McCandless)
LUCENE-6395: Seeking by term ordinal was failing to set the term's bytes in MemoryIndex
(Mike McCandless)
优化(16)
LUCENE-6183, LUCENE-5647: Avoid recompressing stored fields and term vectors when merging segments without deletions. Lucene50Codec's BEST_COMPRESSION mode uses a higher deflate level for more compact storage.
(Robert Muir)
LUCENE-6184: Make BooleanScorer only score windows that contain matches.
(Adrien Grand)
LUCENE-6161: Speed up resolving of deleted terms to docIDs by doing a combined merge sort between deleted terms and segment terms instead of a separate merge sort for each segment. In delete-heavy use cases this can be a sizable speedup.
(Mike McCandless)
LUCENE-6201: BooleanScorer can now deal with values of minShouldMatch that are greater than one and is used when queries produce dense result sets.
(Adrien Grand)
LUCENE-6218: Don't decode frequencies or match all positions when scoring is not needed.
(Robert Muir)
LUCENE-6233 Speed up CheckIndex when the index has term vectors
(Robert Muir, Mike McCandless)
LUCENE-6198: Added the TwoPhaseIterator API, exposed on scorers which is for now only used on phrase queries and conjunctions in order to check positions lazily if the phrase query is in a conjunction with other queries.
(Robert Muir, Adrien Grand, David Smiley)
LUCENE-6244, LUCENE-6251: All boolean queries but those that have a minShouldMatch > 1 now either propagate or take advantage of the two-phase iteration capabilities added in LUCENE-6198.
(Adrien Grand, Robert Muir)
LUCENE-6241: FSDirectory.listAll() doesnt filter out subdirectories anymore, for faster performance. Subdirectories don't matter to Lucene. If you need to filter out non-index files with some custom usage, you may want to look at the IndexFileNames class.
(Robert Muir)
LUCENE-6262: ConstantScoreQuery does not wrap the inner weight anymore when scores are not required.
(Adrien Grand)
LUCENE-6263: MultiCollector automatically caches scores when several collectors need them.
(Adrien Grand)
LUCENE-6275: SloppyPhraseScorer now uses the same logic as ConjunctionScorer in order to advance doc IDs, which takes advantage of the cost() API.
(Adrien Grand)
LUCENE-6290: QueryWrapperFilter propagates approximations and FilteredQuery rewrites to a BooleanQuery when the filter is a QueryWrapperFilter in order to leverage approximations.
(Adrien Grand)
LUCENE-6318: Reduce RAM usage of FieldInfos when there are many fields.
(Mike McCandless, Robert Muir)
LUCENE-6320: Speed up CheckIndex.
(Robert Muir)
LUCENE-4942: Optimized the encoding of PrefixTreeStrategy indexes for non-point data: 33% smaller index, 68% faster indexing, and 44% faster searching. YMMV
(David Smiley)
API 改进 (21)
> .totalMaxDoc and MergePolicy.OneMerge.totalDocCount ->
LUCENE-6204, LUCENE-6208: Simplify CompoundFormat: remove files() and remove files parameter to write().
(Robert Muir)
LUCENE-6217: Add IndexWriter.isOpen and getTragicException.
(Simon Willnauer, Mike McCandless)
LUCENE-6218, LUCENE-6220: Add Collector.needsScores() and needsScores parameter to Query.createWeight().
(Robert Muir, Adrien Grand)
LUCENE-4524, LUCENE-6246, LUCENE-6256, LUCENE-6271: Merge DocsEnum and DocsAndPositionsEnum into a single PostingsEnum iterator. TermsEnum.docs() and TermsEnum.docsAndPositions() are replaced by TermsEnum.postings().
(Alan Woodward, Simon Willnauer, Robert Muir, Ryan Ernst)
LUCENE-6222: Removed TermFilter, use a QueryWrapperFilter(TermQuery) instead. This will be as efficient now that queries can opt out from scoring.
(Adrien Grand)
LUCENE-6269: Removed BooleanFilter, use a QueryWrapperFilter(BooleanQuery) instead.
(Adrien Grand)
LUCENE-6270: Replaced TermsFilter with TermsQuery, use a QueryWrapperFilter(TermsQuery) instead.
(Adrien Grand)
LUCENE-6223: Move BooleanQuery.BooleanWeight to BooleanWeight.
(Robert Muir)
LUCENE-1518: Make Filter extend Query and return 0 as score.
(Uwe Schindler, Adrien Grand)
LUCENE-6245: Force Filter subclasses to implement toString API from Query.
(Ryan Ernst)
LUCENE-6268: Replace FieldValueFilter and DocValuesRangeFilter with equivalent queries that support approximations.
(Adrien Grand)
LUCENE-6289: Replace DocValuesRangeFilter with DocValuesRangeQuery which supports approximations.
(Adrien Grand)
LUCENE-6266: Remove unnecessary Directory params from SegmentInfo.toString, SegmentInfos.files/toString, and SegmentCommitInfo.toString.
(Robert Muir)
LUCENE-6272: Scorer extends DocSetIdIterator rather than DocsEnum
(Alan Woodward)
LUCENE-6281: Removed support for slow collations from lucene/sandbox. Better performance would be achieved through CollationKeyAnalyzer or ICUCollationKeyAnalyzer.
(Adrien Grand)
LUCENE-6286: Removed IndexSearcher methods that take a Filter object. A BooleanQuery with a filter clause must be used instead.
(Adrien Grand)
LUCENE-6300: PrefixFilter, TermRangeFilter and NumericRangeFilter have been removed. Use PrefixQuery, TermRangeQuery and NumericRangeQuery instead.
(Adrien Grand)
LUCENE-6303: Replaced FilterCache with QueryCache and CachingWrapperFilter with CachingWrapperQuery.
(Adrien Grand)
LUCENE-6317: Deprecate DataOutput.writeStringSet and writeStringStringMap. Use writeSetOfStrings/Maps instead.
(Mike McCandless, Robert Muir)
LUCENE-6307: Rename SegmentInfo.getDocCount -> .maxDoc, SegmentInfos.totalDocCount -> .totalMaxDoc, MergeInfo.totalDocCount.totalMaxDoc
(Adrien Grand, Robert Muir, Mike McCandless)
LUCENE-6367: PrefixQuery now subclasses AutomatonQuery, removing the specialized PrefixTermsEnum.
(Robert Muir, Mike McCandless)
其他 (6)
LUCENE-6248: Remove unused odd constants from StandardSyntaxParser.jj
(Dawid Weiss)
LUCENE-6193: Collapse identical catch branches in try-catch statements.
(shalin)
LUCENE-6239: Removed RAMUsageEstimator's sun.misc.Unsafe calls.
(Robert Muir, Dawid Weiss, Uwe Schindler)
LUCENE-6292: Seed StringHelper better.
(Robert Muir)
LUCENE-6333: Refactored queries to delegate their equals and hashcode impls to the super class.
(Lee Hinman via Adrien Grand)
LUCENE-6343: DefaultSimilarity javadocs had the wrong float value to demonstrate precision of encoded norms
(András Péteri via Mike McCandless)
更多详细内容请看更新日志。
Lucene 是apache软件基金会一个开放源代码的全文检索引擎工具包，是一个全文检索引擎的架构，提供了完整的查询引擎和索引引擎，部分文本分析引擎。 Lucene的目的是为软件开发人员提供一个简单易用的工具包，以方便的在目标系统中实现全文检索的功能，或者是以此为基础建立起完整的全文检索引擎。
Lucene 最初是由Doug Cutting所撰写的，是一位资深全文索引/检索专家，曾经是V-Twin搜索引擎的主要开发者，后来在Excite担任高级系统架构设计师，目前从事 于一些INTERNET底层架构的研究。他贡献出Lucene的目标是为各种中小型应用程式加入全文检索功能。
Lucene是apache软件基金会4 jakarta项目组的一个子项目，是一个开放源代码的全文检索引擎工具包，即它不是一个完整的全文检索引擎，而是一个全文检索引擎的架构，提供了完整的查询引擎和索引引擎，部分文本分析引擎（英文与德文两种西方语言）。Lucene的目的是为软件开发人员提供一个简单易用的工具包，以方便的在目标系统中实现全文检索的功能，或者是以此为基础建立起完整的全文检索引擎。