lucene/CHANGES.txt

3613 lines
159 KiB
Plaintext

Lucene Change Log
$Id$
======================= Trunk (not yet released) =======================
Changes in backwards compatibility policy
1. LUCENE-1575: Searchable.search(Weight, Filter, int, Sort) no
longer computes document scores of each hit, by default. If
document scores tracking is still needed, you can call
IndexSearcher.setDefaultFieldSortScoring(true, true) to enable
both per-hit and maxScore tracking; however, this is deprecated
and will be removed in 3.0.
Alternatively, use Searchable.search(Weight, Filter, Collector)
and pass in a TopFieldCollector instance, using the following code
sample:
<code>
TopFieldCollector tfc = TopFieldCollector.create(sort, numHits, fillFields,
true /* trackDocScores */,
true /* trackMaxScore */,
false /* docsInOrder */);
searcher.search(query, tfc);
TopDocs results = tfc.topDocs();
</code>
Note that your Sort object cannot use SortField.AUTO when you
directly instantiate TopFieldCollector.
Also, the method search(Weight, Filter, Collector) was added to
the Searchable interface and the Searcher abstract class, to
replace the deprecated HitCollector versions. If you either
implement Searchable or extend Searcher, you should change you
code to implement this method. If you already extend
IndexSearcher, no further changes are needed to use Collector.
Finally, the values Float.NaN, Float.NEGATIVE_INFINITY and
Float.POSITIVE_INFINITY are not valid scores. Lucene uses these
values internally in certain places, so if you have hits with such
scores it will cause problems. (Shai Erera via Mike McCandless)
2. LUCENE-1687: All methods and parsers from interface ExtendedFieldCache
were moved into FieldCache. ExtendedFieldCache was deprecated and now
contains only a few declarations for binary backwards compatibility and
will be removed in version 3.0. Users of FieldCache and ExtendedFieldCache
will therefore be able to plugin Lucene 2.9 without recompilation.
The auto cache (FieldCache.getAuto) was deprecated. Due to the merge of
ExtendedFieldCache and FieldCache, this method can now additionally return
long[] arrays in addition to int[] and float[] and StringIndex.
The interface changes are only notable for users implementing the interfaces,
which was unlikely done, because there is no possibility to change
Lucene's FieldCache implementation. (Grant Ingersoll, Uwe Schindler)
3. LUCENE-1630: Deprecate Weight in favor of QueryWeight: added
matching methods to Searcher to take QueryWeight and deprecated
those taking Weight. If you have a Weight implementation, you can
turn it into a QueryWeight with QueryWeightWrapper (will be
removed in 3.0). All of the Weight-based methods were implemented
by calling the QueryWeight variants by wrapping the given Weight.
Going forward Searchable will be kept for convenience only and may
be changed between minor releases without any deprecation
process. It is not recommended to implement it, but rather extend
Searcher. (Shai Erera via Mike McCandless)
4. LUCENE-1422, LUCENE-1693: The new TokenStream API (see below) using
Attributes has some backwards breaks in rare cases.
We did our best to make the transition as easy as possible. You should
not have problems, if your tokenizers still implement next(Token) or
next(), the calls are automatically wrapped. The indexer and query parser
use the new API using incrementToken() calls. All core TokenStreams
are implemented using the new API. You can mix old and new API
style TokenFilters/TokenStream. Problems only occur when you have done
the following:
You have overridden next(Token) or next() in one of the non-abstract core
TokenStreams/-Filters. This classes should normally be final, but some
of them are not. In this case next(Token)/next() would never be called.
To early fail with a hard compile/runtime error, the next(Token)/next()
methods in these TokenStreams/-Filters were made final.
(Michael Busch, Uwe Schindler)
5. LUCENE-1763: MergePolicy now requires an IndexWriter instance to
be passed upon instantiation. As a result, IndexWriter was removed
as a method argument from all MergePolicy methods. (Shai Erera via
Mike McCandless)
6. LUCENE-1748: LUCENE-1001 introduced PayloadSpans, but this was a back
compat break and caused custom SpanQuery implementations to fail at runtime
in a variety of ways. This issue attempts to remedy things by causing
a compile time break on custom SpanQuery implementations and removing
the PayloadSpans class, with its functionality now moved to Spans.
(Hugh Cayless, Mark Miller)
Changes in runtime behavior
1. LUCENE-1424: QueryParser now by default uses constant score auto
rewriting when it generates a WildcardQuery and PrefixQuery (it
already does so for TermRangeQuery, as well). Call
setMultiTermRewriteMethod(MultiTermQuery.SCORING_BOOLEAN_QUERY_REWRITE)
to revert to slower BooleanQuery rewriting method. (Mark Miller via Mike
McCandless)
2. LUCENE-1575: As of 2.9, the core collectors as well as
IndexSearcher's search methods that return top N results, no
longer filter out zero scoring documents. If you rely on this
functionality you can use PositiveScoresOnlyCollector like this:
<code>
TopDocsCollector tdc = new TopScoreDocCollector(10);
Collector c = new PositiveScoresOnlyCollector(tdc);
searcher.search(query, c);
TopDocs hits = tdc.topDocs();
...
</code>
3. LUCENE-1604: IndexReader.norms(String field) is now allowed to
return null if the field has no norms, as long as you've
previously called IndexReader.setDisableFakeNorms(true). This
setting now defaults to false (to preserve the fake norms back
compatible behavior) but in 3.0 will be hardwired to true. (Shon
Vella via Mike McCandless).
4. LUCENE-1624: If you open IndexWriter with create=true and
autoCommit=false on an existing index, IndexWriter no longer
writes an empty commit when it's created. (Paul Taylor via Mike
McCandless)
5. LUCENE-1593: When you call Sort() or Sort.setSort(String field,
boolean reverse), the resulting SortField array no longer ends
with SortField.FIELD_DOC (it was unnecessary as Lucene breaks ties
internally by docID). (Shai Erera via Michael McCandless)
6. LUCENE-1542: When the first token(s) have 0 position increment,
IndexWriter used to incorrectly record the position as -1, if no
payload is present, or Integer.MAX_VALUE if a payload is present.
This causes positional queries to fail to match. The bug is now
fixed, but if your app relies on the buggy behavior then you must
call IndexWriter.setAllowMinus1Position(). That API is deprecated
so you must fix your application, and rebuild your index, to not
rely on this behavior by the 3.0 release of Lucene. (Jonathan
Mamou, Mark Miller via Mike McCandless)
7. LUCENE-1708 - IndexReader.document() no longer checks if the document is
deleted. You can call IndexReader.isDeleted(n) prior to calling document(n).
(Shai Erera via Mike McCandless)
8. LUCENE-1715: Finalizers have been removed from the 4 core classes
that still had them, since they will cause GC to take longer, thus
tying up memory for longer, and at best they mask buggy app code.
DirectoryReader (returned from IndexReader.open) & IndexWriter
previously released the write lock during finalize.
SimpleFSDirectory.FSIndexInput closed the descriptor in its
finalizer, and NativeFSLock released the lock. It's possible
applications will be affected by this, but only if the application
is failing to close reader/writers. (Brian Groose via Mike
McCandless)
9. LUCENE-1717: Fixed IndexWriter to account for RAM usage of
buffered deletions. (Mike McCandless)
10. LUCENE-1727: Ensure that fields are stored & retrieved in the
exact order in which they were added to the document. This was
true in all Lucene releases before 2.3, but was broken in 2.3 and
2.4, and is now fixed in 2.9. (Mike McCandless)
11. LUCENE-1678: The addition of Analyzer.reusableTokenStream
accidentally broke back compatibility of external analyzers that
subclassed core analyzers that implemented tokenStream but not
reusableTokenStream. This is now fixed, such that if
reusableTokenStream is invoked on such a subclass, that method
will forcefully fallback to tokenStream. (Mike McCandless)
API Changes
1. LUCENE-1419: Add expert API to set custom indexing chain. This API is
package-protected for now, so we don't have to officially support it.
Yet, it will give us the possibility to try out different consumers
in the chain. (Michael Busch)
2. LUCENE-1427: DocIdSet.iterator() is now allowed to throw
IOException. (Paul Elschot, Mike McCandless)
3. LUCENE-1451: Add public constructors to FSDirectory and subclasses,
and deprecate FSDirectory.getDirectory(). FSDirectory instances
are not required to be singletons per path. (yonik)
4. LUCENE-1422, LUCENE-1693: New TokenStream API that uses a new class called
AttributeSource instead of the now deprecated Token class. All attributes
that the Token class had have been moved into separate classes:
TermAttribute, OffsetAttribute, PositionIncrementAttribute,
PayloadAttribute, TypeAttribute and FlagsAttribute. The new API
is much more flexible; it allows to combine the Attributes arbitrarily
and also to define custom Attributes. The new API has the same performance
as the old next(Token) approach.
For conformance with this new API Tee-/SinkTokenizer was deprecated
and replaced by a new TeeSinkTokenFilter. (Michael Busch, Uwe Schindler)
5. LUCENE-1467: Add nextDoc() and next(int) methods to OpenBitSetIterator.
These methods can be used to avoid additional calls to doc().
(Michael Busch)
6. LUCENE-1468: Deprecate Directory.list(), which sometimes (in
FSDirectory) filters out files that don't look like index files, in
favor of new Directory.listAll(), which does no filtering. Also,
listAll() will never return null; instead, it throws an IOException
(or subclass). Specifically, FSDirectory.listAll() will throw the
newly added NoSuchDirectoryException if the directory does not
exist. (Marcel Reutegger, Mike McCandless)
7. LUCENE-1483: Added new MultiReaderHitCollector which enables faster
hit collection by notifying the collector for each sub-reader
that's visited. All core collectors now use this API. (Mark
Miller, Mike McCandless)
8. LUCENE-1546: Add IndexReader.flush(Map commitUserData), allowing
you to record an opaque commitUserData (maps String -> String) into
the commit written by IndexReader. This matches IndexWriter's
commit methods. (Jason Rutherglen via Mike McCandless)
9. LUCENE-652: Added org.apache.lucene.document.CompressionTools, to
enable compressing & decompressing binary content, external to
Lucene's indexing. Deprecated Field.Store.COMPRESS.
10. LUCENE-1561: Renamed Field.omitTf to Field.omitTermFreqAndPositions
(Otis Gospodnetic via Mike McCandless)
11. LUCENE-1500: Added new InvalidTokenOffsetsException to Highlighter methods
to denote issues when offsets in TokenStream tokens exceed the length of the
provided text. (Mark Harwood)
12. LUCENE-1575: HitCollector is now deprecated in favor of a new
Collector abstract class. For easy migration, people can use
HitCollectorWrapper which translates (wraps) HitCollector into
Collector. Note that this class is also deprecated and will be
removed when HitCollector is removed. Also TimeLimitedCollector
is deprecated in favor of the new TimeLimitingCollector which
extends Collector. (Shai Erera via Mike McCandless)
13. LUCENE-1592: The method TermsEnum.skipTo() was deprecated, because
it is used nowhere in core/contrib and there is only a very ineffective
default implementation available. If you want to position a TermEnum
to another Term, create a new one using IndexReader.terms(Term).
(Uwe Schindler)
14. LUCENE-1621: MultiTermQuery.getTerm() has been deprecated as it does
not make sense for all subclasses of MultiTermQuery. Check individual
subclasses to see if they support getTerm(). (Mark Miller)
15. LUCENE-1636: Make TokenFilter.input final so it's set only
once. (Wouter Heijke, Uwe Schindler via Mike McCandless).
16. LUCENE-1658: Renamed FSDirectory to SimpleFSDirectory (but left an
FSDirectory base class). Added an FSDirectory.open static method
to pick a good default FSDirectory implementation given the OS.
(Michael McCandless, Uwe Schindler)
17. LUCENE-1665: Deprecate SortField.AUTO, to be removed in 3.0.
Instead, when sorting by field, the application should explicitly
state the type of the field. (Mike McCandless)
18. LUCENE-1660: StopFilter, StandardAnalyzer, StopAnalyzer now
require up front specification of enablePositionIncrement (Mike
McCandless)
19. LUCENE-1614: DocIdSetIterator's next() and skipTo() were deprecated in favor
of the new nextDoc() and advance(). The new methods return the doc Id they
landed on, saving an extra call to doc() in most cases.
For easy migration of the code, you can change the calls to next() to
nextDoc() != DocIdSetIterator.NO_MORE_DOCS and similarly for skipTo().
However it is advised that you take advantage of the returned doc ID and not
call doc() following those two.
Also, doc() was deprecated in favor of docID(). docID() should return -1 or
NO_MORE_DOCS if nextDoc/advance were not called yet, or NO_MORE_DOCS if the
iterator has exhausted. Otherwise it should return the current doc ID.
(Shai Erera via Mike McCandless)
20. LUCENE-1672: All ctors/opens and other methods using String/File to
specify the directory in IndexReader, IndexWriter, and IndexSearcher
were deprecated. You should instantiate the Directory manually before
and pass it to these classes (LUCENE-1451, LUCENE-1658).
(Uwe Schindler)
21. LUCENE-1407: Move RemoteSearchable, RemoteCachingWrapperFilter out
of Lucene's core into new contrib/remote package. Searchable no
longer extends java.rmi.Remote (Simon Willnauer via Mike
McCandless)
22. LUCENE-1677: The global property
org.apache.lucene.SegmentReader.class, and
ReadOnlySegmentReader.class are now deprecated, to be removed in
3.0. src/gcj/* has been removed. (Earwin Burrfoot via Mike
McCandless)
23. LUCENE-1673: Deprecated NumberTools in favour of the new
NumericRangeQuery and its new indexing format for numeric or
date values. (Uwe Schindler)
24. LUCENE-1630: Deprecate Weight in favor of QueryWeight, which adds
a scorer(IndexReader, boolean /* scoreDocsInOrder */, boolean /*
topScorer */) method instead of scorer(IndexReader) (now
deprecated). The new method is used by IndexSearcher to mate
between Collector and Scorer orderness of doc IDs. Some Scorers
(like BooleanScorer) are much more efficient if out-of-order
documents scoring is allowed by a Collector. Collector must now
implement acceptsDocsOutOfOrder. If you write a Collector which
does not care about doc ID orderness, it is recommended that you
return true. QueryWeight has the scoresDocsOutOfOrder method,
which by default returns false. If you create a QueryWeight which
will score documents out of order if that's requested, you should
override that method to return true. Also deprecated
BooleanQuery's setAllowDocsOutOfOrder and getAllowDocsOutOfOrder
as they are not needed anymore. BooleanQuery will now score docs
out of order when used with a Collector that can accept docs out
of order. (Shai Erera via Mike McCandless)
25. LUCENE-1466: Changed Tokenizer.input to be a CharStream; added
CharFilter and MappingCharFilter, which allows chaining & mapping
of characters before tokenizers run. (Koji Sekiguchi via Mike
McCandless)
26. LUCENE-1703: Add IndexWriter.waitForMerges. (Tim Smith via Mike
McCandless)
27. LUCENE-1625: CheckIndex's programmatic API now returns separate
classes detailing the status of each component in the index, and
includes more detailed status than previously. (Tim Smith via
Mike McCandless)
28. LUCENE-1713: Deprecated RangeQuery and RangeFilter and renamed to
TermRangeQuery and TermRangeFilter. TermRangeQuery is in constant
score auto rewrite mode by default. The new classes also have new
ctors taking field and term ranges as Strings (see also
LUCENE-1424). (Uwe Schindler)
29. LUCENE-1609: The termInfosIndexDivisor must now be specified
up-front when opening the IndexReader. Attempts to call
IndexReader.setTermInfosIndexDivisor will hit an
UnsupportedOperationException. This was done to enable removal of
all synchronization in TermInfosReader, which previously could
cause threads to pile up in certain cases. (Dan Rosher via Mike
McCandless)
30. LUCENE-1688: Deprecate static final String stop word array in and
StopAnalzyer and replace it with an immutable implementation of
CharArraySet. (Simon Willnauer via Mark Miller)
31. LUCENE-1742: SegmentInfos, SegmentInfo and SegmentReader have been
made public as expert, experimental APIs. These APIs may suddenly
change from release to release (Jason Rutherglen via Mike
McCandless).
32. LUCENE-1754: QueryWeight.scorer() can return null if no documents
are going to be matched by the query. Similarly,
Filter.getDocIdSet() can return null if no documents are going to
be accepted by the Filter. Note that these 'can' return null,
however they don't have to and can return a Scorer/DocIdSet which
does not match / reject all documents. This is already the
behavior of some QueryWeight/Filter implementations, and is
documented here just for emphasis. (Shai Erera via Mike
McCandless)
33. LUCENE-1705: Added IndexWriter.deleteAllDocuments. (Tim Smith via
Mike McCandless)
34. LUCENE-1460: Changed TokenStreams/TokenFilters in contrib to
use the new TokenStream API. (Robert Muir, Michael Busch)
35. LUCENE-1567: Deprecated Queryparser, which will be replaced by a
new QueryParser framework in Lucene 3.0, that is currently located
in contrib. (see New Features 35.)
(Luis Alves and Adriano Campos via Michael Busch)
36. LUCENE-1748: LUCENE-1001 introduced PayloadSpans, but this was a back
compat break and caused custom SpanQuery implementations to fail at runtime
in a variety of ways. This issue attempts to remedy things by causing
a compile time break on custom SpanQuery implementations and removing
the PayloadSpans class, with its functionality now moved to Spans.
(Hugh Cayless, Mark Miller)
Bug fixes
1. LUCENE-1415: MultiPhraseQuery has incorrect hashCode() and equals()
implementation - Leads to Solr Cache misses.
(Todd Feak, Mark Miller via yonik)
2. LUCENE-1327: Fix TermSpans#skipTo() to behave as specified in javadocs
of Terms#skipTo(). (Michael Busch)
3. LUCENE-1573: Do not ignore InterruptedException (caused by
Thread.interrupt()) nor enter deadlock/spin loop. Now, an interrupt
will cause a RuntimeException to be thrown. In 3.0 we will change
public APIs to throw InterruptedException. (Jeremy Volkman vai
Mike McCandless)
4. LUCENE-1590: Fixed stored-only Field instances to not change the
value of omitNorms, omitTermFreqAndPositions in FieldInfo; when you
retrieve such fields they will now have omitNorms=true and
omitTermFreqAndPositions=false (though these values are unused).
(Uwe Schindler via Mike McCandless)
5. LUCENE-1587: RangeQuery#equals() could consider a RangeQuery
without a collator equal to one with a collator.
(Mark Platvoet via Mark Miller)
6. LUCENE-1600: Don't call String.intern unnecessarily in some cases
when loading documents from the index. (P Eger via Mike
McCandless)
7. LUCENE-1611: Fix case where OutOfMemoryException in IndexWriter
could cause "infinite merging" to happen. (Christiaan Fluit via
Mike McCandless)
8. LUCENE-1623: Properly handle back-compatibility of 2.3.x indexes that
contain field names with non-ascii characters. (Mike Streeton via
Mike McCandless)
9. LUCENE-1593: MultiSearcher and ParallelMultiSearcher did not break ties (in
sort) by doc Id in a consistent manner (i.e., if Sort.FIELD_DOC was used vs.
when it wasn't). (Shai Erera via Michael McCandless)
10. LUCENE-1647: Fix case where IndexReader.undeleteAll would cause
the segment's deletion count to be incorrect. (Mike McCandless)
11. LUCENE-1542: When the first token(s) have 0 position increment,
IndexWriter used to incorrectly record the position as -1, if no
payload is present, or Integer.MAX_VALUE if a payload is present.
This causes positional queries to fail to match. The bug is now
fixed, but if your app relies on the buggy behavior then you must
call IndexWriter.setAllowMinus1Position(). That API is deprecated
so you must fix your application, and rebuild your index, to not
rely on this behavior by the 3.0 release of Lucene. (Jonathan
Mamou, Mark Miller via Mike McCandless)
15. LUCENE-1658: Fixed MMapDirectory to correctly throw IOExceptions
on EOF, removed numeric overflow possibilities and added support
for a hack to unmap the buffers on closing IndexInput.
(Uwe Schindler)
16. LUCENE-1681: Fix infinite loop caused by a call to DocValues methods
getMinValue, getMaxValue, getAverageValue. (Simon Willnauer via Mark Miller)
17. LUCENE-1599: Add clone support for SpanQuerys. SpanRegexQuery counts
on this functionality and does not work correctly without it.
(Billow Gao, Mark Miller)
18. LUCENE-1718: Fix termInfosIndexDivisor to carry over to reopened
readers (Mike McCandless)
19. LUCENE-1583: SpanOrQuery skipTo() doesn't always move forwards as Spans
documentation indicates it should. (Moti Nisenson via Mark Miller)
20. LUCENE-1566: Sun JVM Bug
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6478546 causes
invalid OutOfMemoryError when reading too many bytes at once from
a file on 32bit JVMs that have a large maximum heap size. This
fix adds set/getReadChunkSize to FSDirectory so that large reads
are broken into chunks, to work around this JVM bug. On 32bit
JVMs the default chunk size is 100 MB; on 64bit JVMs, which don't
show the bug, the default is Integer.MAX_VALUE. (Simon Willnauer
via Mike McCandless)
21. LUCENE-1448: Added TokenStream.end() to perform end-of-stream
operations (ie to return the end offset of the tokenization).
This is important when multiple fields with the same name are added
to a document, to ensure offsets recorded in term vectors for all
of the instances are correct.
(Mike McCandless, Mark Miller, Michael Busch)
New features
1. LUCENE-1411: Added expert API to open an IndexWriter on a prior
commit, obtained from IndexReader.listCommits. This makes it
possible to rollback changes to an index even after you've closed
the IndexWriter that made the changes, assuming you are using an
IndexDeletionPolicy that keeps past commits around. This is useful
when building transactional support on top of Lucene. (Mike
McCandless)
2. LUCENE-1382: Add an optional arbitrary Map (String -> String)
"commitUserData" to IndexWriter.commit(), which is stored in the
segments file and is then retrievable via
IndexReader.getCommitUserData instance and static methods.
(Shalin Shekhar Mangar via Mike McCandless)
3. LUCENE-1420: Similarity now has a computeNorm method that allows
custom Similarity classes to override how norm is computed. It's
provided a FieldInvertState instance that contains details from
inverting the field. The default impl is boost *
lengthNorm(numTerms), to be backwards compatible. Also added
{set/get}DiscountOverlaps to DefaultSimilarity, to control whether
overlapping tokens (tokens with 0 position increment) should be
counted in lengthNorm. (Andrzej Bialecki via Mike McCandless)
4. LUCENE-1424: Moved constant score query rewrite capability into
MultiTermQuery, allowing TermRangeQuery, PrefixQuery and WildcardQuery
to switch betwen constant-score rewriting or BooleanQuery
expansion rewriting via a new setRewriteMethod method.
Deprecated ConstantScoreRangeQuery (Mark Miller via Mike
McCandless)
5. LUCENE-1461: Added FieldCacheRangeFilter, a RangeFilter for
single-term fields that uses FieldCache to compute the filter. If
your documents all have a single term for a given field, and you
need to create many RangeFilters with varying lower/upper bounds,
then this is likely a much faster way to create the filters than
RangeFilter. FieldCacheRangeFilter allows ranges on all data types,
FieldCache supports (term ranges, byte, short, int, long, float, double).
However, it comes at the expense of added RAM consumption and slower
first-time usage due to populating the FieldCache. It also does not
support collation (Tim Sturge, Matt Ericson via Mike McCandless and
Uwe Schindler)
6. LUCENE-1296: add protected method CachingWrapperFilter.docIdSetToCache
to allow subclasses to choose which DocIdSet implementation to use
(Paul Elschot via Mike McCandless)
7. LUCENE-1390: Added ASCIIFoldingFilter, a Filter that converts
alphabetic, numeric, and symbolic Unicode characters which are not in
the first 127 ASCII characters (the "Basic Latin" Unicode block) into
their ASCII equivalents, if one exists. ISOLatin1AccentFilter, which
handles a subset of this filter, has been deprecated.
(Andi Vajda, Steven Rowe via Mark Miller)
8. LUCENE-1478: Added new SortField constructor allowing you to
specify a custom FieldCache parser to generate numeric values from
terms for a field. (Uwe Schindler via Mike McCandless)
9. LUCENE-1528: Add support for Ideographic Space to the queryparser.
(Luis Alves via Michael Busch)
10. LUCENE-1487: Added FieldCacheTermsFilter, to filter by multiple
terms on single-valued fields. The filter loads the FieldCache
for the field the first time it's called, and subsequent usage of
that field, even with different Terms in the filter, are fast.
(Tim Sturge, Shalin Shekhar Mangar via Mike McCandless).
11. LUCENE-1314: Add clone(), clone(boolean readOnly) and
reopen(boolean readOnly) to IndexReader. Cloning an IndexReader
gives you a new reader which you can make changes to (deletions,
norms) without affecting the original reader. Now, with clone or
reopen you can change the readOnly of the original reader. (Jason
Rutherglen, Mike McCandless)
12. LUCENE-1506: Added FilteredDocIdSet, an abstract class which you
subclass to implement the "match" method to accept or reject each
docID. Unlike ChainedFilter (under contrib/misc),
FilteredDocIdSet never requires you to materialize the full
bitset. Instead, match() is called on demand per docID. (John
Wang via Mike McCandless)
13. LUCENE-1398: Add ReverseStringFilter to contrib/analyzers, a filter
to reverse the characters in each token. (Koji Sekiguchi via yonik)
14. LUCENE-1551: Add expert IndexReader.reopen(IndexCommit) to allow
efficiently opening a new reader on a specific commit, sharing
resources with the original reader. (Torin Danil via Mike
McCandless)
15. LUCENE-1434: Added org.apache.lucene.util.IndexableBinaryStringTools,
to encode byte[] as String values that are valid terms, and
maintain sort order of the original byte[] when the bytes are
interpreted as unsigned. (Steven Rowe via Mike McCandless)
16. LUCENE-1543: Allow MatchAllDocsQuery to optionally use norms from
a specific fields to set the score for a document. (Karl Wettin
via Mike McCandless)
17. LUCENE-1586: Add IndexReader.getUniqueTermCount(). (Mike
McCandless via Derek)
18. LUCENE-1516: Added "near real-time search" to IndexWriter, via a
new expert getReader() method. This method returns a reader that
searches the full index, including any uncommitted changes in the
current IndexWriter session. This should result in a faster
turnaround than the normal approach of commiting the changes and
then reopening a reader. (Jason Rutherglen via Mike McCandless)
19. LUCENE-1603: Added new MultiTermQueryWrapperFilter, to wrap any
MultiTermQuery as a Filter. Also made some improvements to
MultiTermQuery: return DocIdSet.EMPTY_DOCIDSET if there are no
terms in the enum; track the total number of terms it visited
during rewrite (getTotalNumberOfTerms). FilteredTermEnum is also
more friendly to subclassing. (Uwe Schindler via Mike McCandless)
20. LUCENE-1605: Added BitVector.subset(). (Jeremy Volkman via Mike
McCandless)
21. LUCENE-1618: Added FileSwitchDirectory that enables files with
specified extensions to be stored in a primary directory and the
rest of the files to be stored in the secondary directory. For
example, this can be useful for the large doc-store (stored
fields, term vectors) files in FSDirectory and the rest of the
index files in a RAMDirectory. (Jason Rutherglen via Mike
McCandless)
22. LUCENE-1494: Added FieldMaskingSpanQuery which can be used to
cross-correlate Spans from different fields.
(Paul Cowan and Chris Hostetter)
23. LUCENE-1634: Add calibrateSizeByDeletes to LogMergePolicy, to take
deletions into account when considering merges. (Yasuhiro Matsuda
via Mike McCandless)
24. LUCENE-1550: Added new n-gram based String distance measure for spell checking.
See the Javadocs for NGramDistance.java for a reference paper on why
this is helpful (Tom Morton via Grant Ingersoll)
25. LUCENE-1470, LUCENE-1582, LUCENE-1602, LUCENE-1673, LUCENE-1701, LUCENE-1712:
Added NumericRangeQuery and NumericRangeFilter, a fast alternative to
RangeQuery/RangeFilter for numeric searches. They depend on a specific
structure of terms in the index that can be created by indexing
using the new NumericField or NumericTokenStream classes. NumericField
can only be used for indexing and optionally stores the values as
string representation in the doc store. Documents returned from
IndexReader/IndexSearcher will return only the String value using
the standard Fieldable interface. NumericFields can be sorted on
and loaded into the FieldCache. (Uwe Schindler, Yonik Seeley,
Mike McCandless)
26. LUCENE-1405: Added support for Ant resource collections in contrib/ant
<index> task. (Przemyslaw Sztoch via Erik Hatcher)
27. LUCENE-1699: Allow setting a TokenStream on Field/Fieldable for indexing
in conjunction with any other ways to specify stored field values,
currently binary or string values. (yonik)
28. LUCENE-1701: Made the standard FieldCache.Parsers public and added
parsers for fields generated using NumericField/NumericTokenStream.
All standard parsers now also implement Serializable and enforce
their singleton status. (Uwe Schindler, Mike McCandless)
29. LUCENE-1741: User configureable maximum chunk size in MMapDirectory.
On 32 bit platforms, the address space can be very fragmented, so
one big ByteBuffer for the whole file may not fit into address space.
(Eks Dev via Uwe Schindler)
30. LUCENE-1644: Enable 4 rewrite modes for queries deriving from
MultiTermQuery (WildcardQuery, PrefixQuery, TermRangeQuery,
NumericRangeQuery): CONSTANT_SCORE_FILTER_REWRITE first creates a
filter and then assigns constant score (boost) to docs;
CONSTANT_SCORE_BOOLEAN_QUERY_REWRITE create a BooleanQuery but
uses a constant score (boost); SCORING_BOOLEAN_QUERY_REWRITE also
creates a BooleanQuery but keeps the BooleanQuery's scores;
CONSTANT_SCORE_AUTO_REWRITE tries to pick the most performant
constant-score rewrite method. (Mike McCandless)
31. LUCENE-1448: Added TokenStream.end(), to perform end-of-stream
operations. This is currently used to fix offset problems when
multiple fields with the same name are added to a document.
(Mike McCandless, Mark Miller, Michael Busch)
32. LUCENE-1567: Added a new QueryParser framework to contrib, that
allows implementing a new query syntax in a flexible and efficient
way. This new QueryParser will be moved to Lucene's core in release
3.0 and will then replace the current core QueryParser, which
has been deprecated with this patch.
(Luis Alves and Adriano Campos via Michael Busch)
33. LUCENE-1776: Add an option to not collect payloads for an ordered
SpanNearQuery. Payloads were not lazily loaded in this case as
the javadocs implied. If you have payloads and want to use an ordered
SpanNearQuery that does not need to use the payloads, you can
disable loading them with a new constructor switch. (Mark Miller)
Optimizations
1. LUCENE-1427: Fixed QueryWrapperFilter to not waste time computing
scores of the query, since they are just discarded. Also, made it
more efficient (single pass) by not creating & populating an
intermediate OpenBitSet (Paul Elschot, Mike McCandless)
2. LUCENE-1443: Performance improvement for OpenBitSetDISI.inPlaceAnd()
(Paul Elschot via yonik)
3. LUCENE-1484: Remove synchronization of IndexReader.document() by
using CloseableThreadLocal internally. (Jason Rutherglen via Mike
McCandless).
4. LUCENE-1224: Short circuit FuzzyQuery.rewrite when input token length
is small compared to minSimilarity. (Timo Nentwig, Mark Miller)
5. LUCENE-1316: MatchAllDocsQuery now avoids the synchronized
IndexReader.isDeleted() call per document, by directly accessing
the underlying deleteDocs BitVector. This improves performance
with non-readOnly readers, especially in a multi-threaded
environment. (Todd Feak, Yonik Seeley, Jason Rutherglen via Mike
McCandless)
6. LUCENE-1483: When searching over multiple segments we now visit
each sub-reader one at a time. This speeds up warming, since
FieldCache entries (if required) can be shared across reopens for
those segments that did not change, and also speeds up searches
that sort by relevance or by field values. (Mark Miller, Mike
McCandless)
7. LUCENE-1575: The new Collector class decouples collect() from
score computation. Collector.setScorer is called to establish the
current Scorer in-use per segment. Collectors that require the
score should then call Scorer.score() per hit inside
collect(). (Shai Erera via Mike McCandless)
8. LUCENE-1596: MultiTermDocs speedup when set with
MultiTermDocs.seek(MultiTermEnum) (yonik)
9. LUCENE-1653: Avoid creating a Calendar in every call to
DateTools#dateToString, DateTools#timeToString and
DateTools#round. (Shai Erera via Mark Miller)
10. LUCENE-1688: Deprecate static final String stop word array and
replace it with an immutable implementation of CharArraySet.
Removes conversions between Set and array.
(Simon Willnauer via Mark Miller)
11. LUCENE-1754: BooleanQuery.queryWeight.scorer() will return null if
it won't match any documents (e.g. if there are no required and
optional scorers, or not enough optional scorers to satisfy
minShouldMatch). (Shai Erera via Mike McCandless)
12. LUCENE-1607: To speed up string interning for commonly used
strings, the StringHelper.intern() interface was added with a
default implementation that uses a lockless cache.
(Earwin Burrfoot, yonik)
Documentation
Build
1. LUCENE-1440: Add new targets to build.xml that allow downloading
and executing the junit testcases from an older release for
backwards-compatibility testing. (Michael Busch)
2. LUCENE-1446: Add compatibility tag to common-build.xml and run
backwards-compatibility tests in the nightly build. (Michael Busch)
3. LUCENE-1529: Properly test "drop-in" replacement of jar with
backwards-compatibility tests. (Mike McCandless, Michael Busch)
Test Cases
======================= Release 2.4.1 2009-03-09 =======================
API Changes
1. LUCENE-1186: Add Analyzer.close() to free internal ThreadLocal
resources. (Christian Kohlschütter via Mike McCandless)
Bug fixes
1. LUCENE-1452: Fixed silent data-loss case whereby binary fields are
truncated to 0 bytes during merging if the segments being merged
are non-congruent (same field name maps to different field
numbers). This bug was introduced with LUCENE-1219. (Andrzej
Bialecki via Mike McCandless).
2. LUCENE-1429: Don't throw incorrect IllegalStateException from
IndexWriter.close() if you've hit an OOM when autoCommit is true.
(Mike McCandless)
3. LUCENE-1474: If IndexReader.flush() is called twice when there were
pending deletions, it could lead to later false AssertionError
during IndexReader.open. (Mike McCandless)
4. LUCENE-1430: Fix false AlreadyClosedException from IndexReader.open
(masking an actual IOException) that takes String or File path.
(Mike McCandless)
5. LUCENE-1442: Multiple-valued NOT_ANALYZED fields can double-count
token offsets. (Mike McCandless)
6. LUCENE-1453: Ensure IndexReader.reopen()/clone() does not result in
incorrectly closing the shared FSDirectory. This bug would only
happen if you use IndexReader.open() with a File or String argument.
The returned readers are wrapped by a FilterIndexReader that
correctly handles closing of directory after reopen()/clone().
(Mark Miller, Uwe Schindler, Mike McCandless)
7. LUCENE-1457: Fix possible overflow bugs during binary
searches. (Mark Miller via Mike McCandless)
8. LUCENE-1459: Fix CachingWrapperFilter to not throw exception if
both bits() and getDocIdSet() methods are called. (Matt Jones via
Mike McCandless)
9. LUCENE-1519: Fix int overflow bug during segment merging. (Deepak
via Mike McCandless)
10. LUCENE-1521: Fix int overflow bug when flushing segment.
(Shon Vella via Mike McCandless).
11. LUCENE-1544: Fix deadlock in IndexWriter.addIndexes(IndexReader[]).
(Mike McCandless via Doug Sale)
12. LUCENE-1547: Fix rare thread safety issue if two threads call
IndexWriter commit() at the same time. (Mike McCandless)
13. LUCENE-1465: NearSpansOrdered returns payloads from first possible match
rather than the correct, shortest match; Payloads could be returned even
if the max slop was exceeded; The wrong payload could be returned in
certain situations. (Jonathan Mamou, Greg Shackles, Mark Miller)
14. LUCENE-1186: Add Analyzer.close() to free internal ThreadLocal
resources. (Christian Kohlschütter via Mike McCandless)
15. LUCENE-1552: Fix IndexWriter.addIndexes(IndexReader[]) to properly
rollback IndexWriter's internal state on hitting an
exception. (Scott Garland via Mike McCandless)
======================= Release 2.4.0 2008-10-06 =======================
Changes in backwards compatibility policy
1. LUCENE-1340: In a minor change to Lucene's backward compatibility
policy, we are now allowing the Fieldable interface to have
changes, within reason, and made on a case-by-case basis. If an
application implements it's own Fieldable, please be aware of
this. Otherwise, no need to be concerned. This is in effect for
all 2.X releases, starting with 2.4. Also note, that in all
likelihood, Fieldable will be changed in 3.0.
Changes in runtime behavior
1. LUCENE-1151: Fix StandardAnalyzer to not mis-identify host names
(eg lucene.apache.org) as an ACRONYM. To get back to the pre-2.4
backwards compatible, but buggy, behavior, you can either call
StandardAnalyzer.setDefaultReplaceInvalidAcronym(false) (static
method), or, set system property
org.apache.lucene.analysis.standard.StandardAnalyzer.replaceInvalidAcronym
to "false" on JVM startup. All StandardAnalyzer instances created
after that will then show the pre-2.4 behavior. Alternatively,
you can call setReplaceInvalidAcronym(false) to change the
behavior per instance of StandardAnalyzer. This backwards
compatibility will be removed in 3.0 (hardwiring the value to
true). (Mike McCandless)
2. LUCENE-1044: IndexWriter with autoCommit=true now commits (such
that a reader can see the changes) far less often than it used to.
Previously, every flush was also a commit. You can always force a
commit by calling IndexWriter.commit(). Furthermore, in 3.0,
autoCommit will be hardwired to false (IndexWriter constructors
that take an autoCommit argument have been deprecated) (Mike
McCandless)
3. LUCENE-1335: IndexWriter.addIndexes(Directory[]) and
addIndexesNoOptimize no longer allow the same Directory instance
to be passed in more than once. Internally, IndexWriter uses
Directory and segment name to uniquely identify segments, so
adding the same Directory more than once was causing duplicates
which led to problems (Mike McCandless)
4. LUCENE-1396: Improve PhraseQuery.toString() so that gaps in the
positions are indicated with a ? and multiple terms at the same
position are joined with a |. (Andrzej Bialecki via Mike
McCandless)
API Changes
1. LUCENE-1084: Changed all IndexWriter constructors to take an
explicit parameter for maximum field size. Deprecated all the
pre-existing constructors; these will be removed in release 3.0.
NOTE: these new constructors set autoCommit to false. (Steven
Rowe via Mike McCandless)
2. LUCENE-584: Changed Filter API to return a DocIdSet instead of a
java.util.BitSet. This allows using more efficient data structures
for Filters and makes them more flexible. This deprecates
Filter.bits(), so all filters that implement this outside
the Lucene code base will need to be adapted. See also the javadocs
of the Filter class. (Paul Elschot, Michael Busch)
3. LUCENE-1044: Added IndexWriter.commit() which flushes any buffered
adds/deletes and then commits a new segments file so readers will
see the changes. Deprecate IndexWriter.flush() in favor of
IndexWriter.commit(). (Mike McCandless)
4. LUCENE-325: Added IndexWriter.expungeDeletes methods, which
consult the MergePolicy to find merges necessary to merge away all
deletes from the index. This should be a somewhat lower cost
operation than optimize. (John Wang via Mike McCandless)
5. LUCENE-1233: Return empty array instead of null when no fields
match the specified name in these methods in Document:
getFieldables, getFields, getValues, getBinaryValues. (Stefan
Trcek vai Mike McCandless)
6. LUCENE-1234: Make BoostingSpanScorer protected. (Andi Vajda via Grant Ingersoll)
7. LUCENE-510: The index now stores strings as true UTF-8 bytes
(previously it was Java's modified UTF-8). If any text, either
stored fields or a token, has illegal UTF-16 surrogate characters,
these characters are now silently replaced with the Unicode
replacement character U+FFFD. This is a change to the index file
format. (Marvin Humphrey via Mike McCandless)
8. LUCENE-852: Let the SpellChecker caller specify IndexWriter mergeFactor
and RAM buffer size. (Otis Gospodnetic)
9. LUCENE-1290: Deprecate org.apache.lucene.search.Hits, Hit and HitIterator
and remove all references to these classes from the core. Also update demos
and tutorials. (Michael Busch)
10. LUCENE-1288: Add getVersion() and getGeneration() to IndexCommit.
getVersion() returns the same value that IndexReader.getVersion()
returns when the reader is opened on the same commit. (Jason
Rutherglen via Mike McCandless)
11. LUCENE-1311: Added IndexReader.listCommits(Directory) static
method to list all commits in a Directory, plus IndexReader.open
methods that accept an IndexCommit and open the index as of that
commit. These methods are only useful if you implement a custom
DeletionPolicy that keeps more than the last commit around.
(Jason Rutherglen via Mike McCandless)
12. LUCENE-1325: Added IndexCommit.isOptimized(). (Shalin Shekhar
Mangar via Mike McCandless)
13. LUCENE-1324: Added TokenFilter.reset(). (Shai Erera via Mike
McCandless)
14. LUCENE-1340: Added Fieldable.omitTf() method to skip indexing term
frequency, positions and payloads. This saves index space, and
indexing/searching time. (Eks Dev via Mike McCandless)
15. LUCENE-1219: Add basic reuse API to Fieldable for binary fields:
getBinaryValue/Offset/Length(); currently only lazy fields reuse
the provided byte[] result to getBinaryValue. (Eks Dev via Mike
McCandless)
16. LUCENE-1334: Add new constructor for Term: Term(String fieldName)
which defaults term text to "". (DM Smith via Mike McCandless)
17. LUCENE-1333: Added Token.reinit(*) APIs to re-initialize (reuse) a
Token. Also added term() method to return a String, with a
performance penalty clearly documented. Also implemented
hashCode() and equals() in Token, and fixed all core and contrib
analyzers to use the re-use APIs. (DM Smith via Mike McCandless)
18. LUCENE-1329: Add optional readOnly boolean when opening an
IndexReader. A readOnly reader is not allowed to make changes
(deletions, norms) to the index; in exchanged, the isDeleted
method, often a bottleneck when searching with many threads, is
not synchronized. The default for readOnly is still false, but in
3.0 the default will become true. (Jason Rutherglen via Mike
McCandless)
19. LUCENE-1367: Add IndexCommit.isDeleted(). (Shalin Shekhar Mangar
via Mike McCandless)
20. LUCENE-1061: Factored out all "new XXXQuery(...)" in
QueryParser.java into protected methods newXXXQuery(...) so that
subclasses can create their own subclasses of each Query type.
(John Wang via Mike McCandless)
21. LUCENE-753: Added new Directory implementation
org.apache.lucene.store.NIOFSDirectory, which uses java.nio's
FileChannel to do file reads. On most non-Windows platforms, with
many threads sharing a single searcher, this may yield sizable
improvement to query throughput when compared to FSDirectory,
which only allows a single thread to read from an open file at a
time. (Jason Rutherglen via Mike McCandless)
22. LUCENE-1371: Added convenience method TopDocs Searcher.search(Query query, int n).
(Mike McCandless)
23. LUCENE-1356: Allow easy extensions of TopDocCollector by turning
constructor and fields from package to protected. (Shai Erera
via Doron Cohen)
24. LUCENE-1375: Added convenience method IndexCommit.getTimestamp,
which is equivalent to
getDirectory().fileModified(getSegmentsFileName()). (Mike McCandless)
23. LUCENE-1366: Rename Field.Index options to be more accurate:
TOKENIZED becomes ANALYZED; UN_TOKENIZED becomes NOT_ANALYZED;
NO_NORMS becomes NOT_ANALYZED_NO_NORMS and a new ANALYZED_NO_NORMS
is added. (Mike McCandless)
24. LUCENE-1131: Added numDeletedDocs method to IndexReader (Otis Gospodnetic)
Bug fixes
1. LUCENE-1134: Fixed BooleanQuery.rewrite to only optimize a single
clause query if minNumShouldMatch<=0. (Shai Erera via Michael Busch)
2. LUCENE-1169: Fixed bug in IndexSearcher.search(): searching with
a filter might miss some hits because scorer.skipTo() is called
without checking if the scorer is already at the right position.
scorer.skipTo(scorer.doc()) is not a NOOP, it behaves as
scorer.next(). (Eks Dev, Michael Busch)
3. LUCENE-1182: Added scorePayload to SimilarityDelegator (Andi Vajda via Grant Ingersoll)
4. LUCENE-1213: MultiFieldQueryParser was ignoring slop in case
of a single field phrase. (Trejkaz via Doron Cohen)
5. LUCENE-1228: IndexWriter.commit() was not updating the index version and as
result IndexReader.reopen() failed to sense index changes. (Doron Cohen)
6. LUCENE-1267: Added numDocs() and maxDoc() to IndexWriter;
deprecated docCount(). (Mike McCandless)
7. LUCENE-1274: Added new prepareCommit() method to IndexWriter,
which does phase 1 of a 2-phase commit (commit() does phase 2).
This is needed when you want to update an index as part of a
transaction involving external resources (eg a database). Also
deprecated abort(), renaming it to rollback(). (Mike McCandless)
8. LUCENE-1003: Stop RussianAnalyzer from removing numbers.
(TUSUR OpenTeam, Dmitry Lihachev via Otis Gospodnetic)
9. LUCENE-1152: SpellChecker fix around clearIndex and indexDictionary
methods, plus removal of IndexReader reference.
(Naveen Belkale via Otis Gospodnetic)
10. LUCENE-1046: Removed dead code in SpellChecker
(Daniel Naber via Otis Gospodnetic)
11. LUCENE-1189: Fixed the QueryParser to handle escaped characters within
quoted terms correctly. (Tomer Gabel via Michael Busch)
12. LUCENE-1299: Fixed NPE in SpellChecker when IndexReader is not null and field is (Grant Ingersoll)
13. LUCENE-1303: Fixed BoostingTermQuery's explanation to be marked as a Match
depending only upon the non-payload score part, regardless of the effect of
the payload on the score. Prior to this, score of a query containing a BTQ
differed from its explanation. (Doron Cohen)
14. LUCENE-1310: Fixed SloppyPhraseScorer to work also for terms repeating more
than twice in the query. (Doron Cohen)
15. LUCENE-1351: ISOLatin1AccentFilter now cleans additional ligatures (Cedrik Lime via Grant Ingersoll)
16. LUCENE-1383: Workaround a nasty "leak" in Java's builtin
ThreadLocal, to prevent Lucene from causing unexpected
OutOfMemoryError in certain situations (notably J2EE
applications). (Chris Lu via Mike McCandless)
New features
1. LUCENE-1137: Added Token.set/getFlags() accessors for passing more information about a Token through the analysis
process. The flag is not indexed/stored and is thus only used by analysis.
2. LUCENE-1147: Add -segment option to CheckIndex tool so you can
check only a specific segment or segments in your index. (Mike
McCandless)
3. LUCENE-1045: Reopened this issue to add support for short and bytes.
4. LUCENE-584: Added new data structures to o.a.l.util, such as
OpenBitSet and SortedVIntList. These extend DocIdSet and can
directly be used for Filters with the new Filter API. Also changed
the core Filters to use OpenBitSet instead of java.util.BitSet.
(Paul Elschot, Michael Busch)
5. LUCENE-494: Added QueryAutoStopWordAnalyzer to allow for the automatic removal, from a query of frequently occurring terms.
This Analyzer is not intended for use during indexing. (Mark Harwood via Grant Ingersoll)
6. LUCENE-1044: Change Lucene to properly "sync" files after
committing, to ensure on a machine or OS crash or power cut, even
with cached writes, the index remains consistent. Also added
explicit commit() method to IndexWriter to force a commit without
having to close. (Mike McCandless)
7. LUCENE-997: Add search timeout (partial) support.
A TimeLimitedCollector was added to allow limiting search time.
It is a partial solution since timeout is checked only when
collecting a hit, and therefore a search for rare words in a
huge index might not stop within the specified time.
(Sean Timm via Doron Cohen)
8. LUCENE-1184: Allow SnapshotDeletionPolicy to be re-used across
close/re-open of IndexWriter while still protecting an open
snapshot (Tim Brennan via Mike McCandless)
9. LUCENE-1194: Added IndexWriter.deleteDocuments(Query) to delete
documents matching the specified query. Also added static unlock
and isLocked methods (deprecating the ones in IndexReader). (Mike
McCandless)
10. LUCENE-1201: Add IndexReader.getIndexCommit() method. (Tim Brennan
via Mike McCandless)
11. LUCENE-550: Added InstantiatedIndex implementation. Experimental
Index store similar to MemoryIndex but allows for multiple documents
in memory. (Karl Wettin via Grant Ingersoll)
12. LUCENE-400: Added word based n-gram filter (in contrib/analyzers) called ShingleFilter and an Analyzer wrapper
that wraps another Analyzer's token stream with a ShingleFilter (Sebastian Kirsch, Steve Rowe via Grant Ingersoll)
13. LUCENE-1166: Decomposition tokenfilter for languages like German and Swedish (Thomas Peuss via Grant Ingersoll)
14. LUCENE-1187: ChainedFilter and BooleanFilter now work with new Filter API
and DocIdSetIterator-based filters. Backwards-compatibility with old
BitSet-based filters is ensured. (Paul Elschot via Michael Busch)
15. LUCENE-1295: Added new method to MoreLikeThis for retrieving interesting terms and made retrieveTerms(int) public. (Grant Ingersoll)
16. LUCENE-1298: MoreLikeThis can now accept a custom Similarity (Grant Ingersoll)
17. LUCENE-1297: Allow other string distance measures for the SpellChecker
(Thomas Morton via Otis Gospodnetic)
18. LUCENE-1001: Provide access to Payloads via Spans. All existing Span Query implementations in Lucene implement. (Mark Miller, Grant Ingersoll)
19. LUCENE-1354: Provide programmatic access to CheckIndex (Grant Ingersoll, Mike McCandless)
20. LUCENE-1279: Add support for Collators to RangeFilter/Query and Query Parser. (Steve Rowe via Grant Ingersoll)
Optimizations
1. LUCENE-705: When building a compound file, use
RandomAccessFile.setLength() to tell the OS/filesystem to
pre-allocate space for the file. This may improve fragmentation
in how the CFS file is stored, and allows us to detect an upcoming
disk full situation before actually filling up the disk. (Mike
McCandless)
2. LUCENE-1120: Speed up merging of term vectors by bulk-copying the
raw bytes for each contiguous range of non-deleted documents.
(Mike McCandless)
3. LUCENE-1185: Avoid checking if the TermBuffer 'scratch' in
SegmentTermEnum is null for every call of scanTo().
(Christian Kohlschuetter via Michael Busch)
4. LUCENE-1217: Internal to Field.java, use isBinary instead of
runtime type checking for possible speedup of binaryValue().
(Eks Dev via Mike McCandless)
5. LUCENE-1183: Optimized TRStringDistance class (in contrib/spell) that uses
less memory than the previous version. (Cédrik LIME via Otis Gospodnetic)
6. LUCENE-1195: Improve term lookup performance by adding a LRU cache to the
TermInfosReader. In performance experiments the speedup was about 25% on
average on mid-size indexes with ~500,000 documents for queries with 3
terms and about 7% on larger indexes with ~4.3M documents. (Michael Busch)
Documentation
1. LUCENE-1236: Added some clarifying remarks to EdgeNGram*.java (Hiroaki Kawai via Grant Ingersoll)
2. LUCENE-1157 and LUCENE-1256: HTML changes log, created automatically
from CHANGES.txt. This HTML file is currently visible only via developers page.
(Steven Rowe via Doron Cohen)
3. LUCENE-1349: Fieldable can now be changed without breaking backward compatibility rules (within reason. See the note at
the top of this file and also on Fieldable.java). (Grant Ingersoll)
Build
1. LUCENE-1153: Added JUnit JAR to new lib directory. Updated build to rely on local JUnit instead of ANT/lib.
2. LUCENE-1202: Small fixes to the way Clover is used to work better
with contribs. Of particular note: a single clover db is used
regardless of whether tests are run globally or in the specific
contrib directories.
3. LUCENE-1353: Javacc target in contrib/miscellaneous for
generating the precedence query parser.
Test Cases
1. LUCENE-1238: Fixed intermittent failures of TestTimeLimitedCollector.testTimeoutMultiThreaded.
Within this fix, "greedy" flag was added to TimeLimitedCollector, to allow the wrapped
collector to collect also the last doc, after allowed-tTime passed. (Doron Cohen)
2. LUCENE-1348: relax TestTimeLimitedCollector to not fail due to
timeout exceeded (just because test machine is very busy).
======================= Release 2.3.2 2008-05-05 =======================
Bug fixes
1. LUCENE-1191: On hitting OutOfMemoryError in any index-modifying
methods in IndexWriter, do not commit any further changes to the
index to prevent risk of possible corruption. (Mike McCandless)
2. LUCENE-1197: Fixed issue whereby IndexWriter would flush by RAM
too early when TermVectors were in use. (Mike McCandless)
3. LUCENE-1198: Don't corrupt index if an exception happens inside
DocumentsWriter.init (Mike McCandless)
4. LUCENE-1199: Added defensive check for null indexReader before
calling close in IndexModifier.close() (Mike McCandless)
5. LUCENE-1200: Fix rare deadlock case in addIndexes* when
ConcurrentMergeScheduler is in use (Mike McCandless)
6. LUCENE-1208: Fix deadlock case on hitting an exception while
processing a document that had triggered a flush (Mike McCandless)
7. LUCENE-1210: Fix deadlock case on hitting an exception while
starting a merge when using ConcurrentMergeScheduler (Mike McCandless)
8. LUCENE-1222: Fix IndexWriter.doAfterFlush to always be called on
flush (Mark Ferguson via Mike McCandless)
9. LUCENE-1226: Fixed IndexWriter.addIndexes(IndexReader[]) to commit
successfully created compound files. (Michael Busch)
10. LUCENE-1150: Re-expose StandardTokenizer's constants publicly;
this was accidentally lost with LUCENE-966. (Nicolas Lalevée via
Mike McCandless)
11. LUCENE-1262: Fixed bug in BufferedIndexReader.refill whereby on
hitting an exception in readInternal, the buffer is incorrectly
filled with stale bytes such that subsequent calls to readByte()
return incorrect results. (Trejkaz via Mike McCandless)
12. LUCENE-1270: Fixed intermittent case where IndexWriter.close()
would hang after IndexWriter.addIndexesNoOptimize had been
called. (Stu Hood via Mike McCandless)
Build
1. LUCENE-1230: Include *pom.xml* in source release files. (Michael Busch)
======================= Release 2.3.1 2008-02-22 =======================
Bug fixes
1. LUCENE-1168: Fixed corruption cases when autoCommit=false and
documents have mixed term vectors (Suresh Guvvala via Mike
McCandless).
2. LUCENE-1171: Fixed some cases where OOM errors could cause
deadlock in IndexWriter (Mike McCandless).
3. LUCENE-1173: Fixed corruption case when autoCommit=false and bulk
merging of stored fields is used (Yonik via Mike McCandless).
4. LUCENE-1163: Fixed bug in CharArraySet.contains(char[] buffer, int
offset, int len) that was ignoring offset and thus giving the
wrong answer. (Thomas Peuss via Mike McCandless)
5. LUCENE-1177: Fix rare case where IndexWriter.optimize might do too
many merges at the end. (Mike McCandless)
6. LUCENE-1176: Fix corruption case when documents with no term
vector fields are added before documents with term vector fields.
(Mike McCandless)
7. LUCENE-1179: Fixed assert statement that was incorrectly
preventing Fields with empty-string field name from working.
(Sergey Kabashnyuk via Mike McCandless)
======================= Release 2.3.0 2008-01-21 =======================
Changes in runtime behavior
1. LUCENE-994: Defaults for IndexWriter have been changed to maximize
out-of-the-box indexing speed. First, IndexWriter now flushes by
RAM usage (16 MB by default) instead of a fixed doc count (call
IndexWriter.setMaxBufferedDocs to get backwards compatible
behavior). Second, ConcurrentMergeScheduler is used to run merges
using background threads (call IndexWriter.setMergeScheduler(new
SerialMergeScheduler()) to get backwards compatible behavior).
Third, merges are chosen based on size in bytes of each segment
rather than document count of each segment (call
IndexWriter.setMergePolicy(new LogDocMergePolicy()) to get
backwards compatible behavior).
NOTE: users of ParallelReader must change back all of these
defaults in order to ensure the docIDs "align" across all parallel
indices.
(Mike McCandless)
2. LUCENE-1045: SortField.AUTO didn't work with long. When detecting
the field type for sorting automatically, numbers used to be
interpreted as int, then as float, if parsing the number as an int
failed. Now the detection checks for int, then for long,
then for float. (Daniel Naber)
API Changes
1. LUCENE-843: Added IndexWriter.setRAMBufferSizeMB(...) to have
IndexWriter flush whenever the buffered documents are using more
than the specified amount of RAM. Also added new APIs to Token
that allow one to set a char[] plus offset and length to specify a
token (to avoid creating a new String() for each Token). (Mike
McCandless)
2. LUCENE-963: Add setters to Field to allow for re-using a single
Field instance during indexing. This is a sizable performance
gain, especially for small documents. (Mike McCandless)
3. LUCENE-969: Add new APIs to Token, TokenStream and Analyzer to
permit re-using of Token and TokenStream instances during
indexing. Changed Token to use a char[] as the store for the
termText instead of String. This gives faster tokenization
performance (~10-15%). (Mike McCandless)
4. LUCENE-847: Factored MergePolicy, which determines which merges
should take place and when, as well as MergeScheduler, which
determines when the selected merges should actually run, out of
IndexWriter. The default merge policy is now
LogByteSizeMergePolicy (see LUCENE-845) and the default merge
scheduler is now ConcurrentMergeScheduler (see
LUCENE-870). (Steven Parkes via Mike McCandless)
5. LUCENE-1052: Add IndexReader.setTermInfosIndexDivisor(int) method
that allows you to reduce memory usage of the termInfos by further
sub-sampling (over the termIndexInterval that was used during
indexing) which terms are loaded into memory. (Chuck Williams,
Doug Cutting via Mike McCandless)
6. LUCENE-743: Add IndexReader.reopen() method that re-opens an
existing IndexReader (see New features -> 8.) (Michael Busch)
7. LUCENE-1062: Add setData(byte[] data),
setData(byte[] data, int offset, int length), getData(), getOffset()
and clone() methods to o.a.l.index.Payload. Also add the field name
as arg to Similarity.scorePayload(). (Michael Busch)
8. LUCENE-982: Add IndexWriter.optimize(int maxNumSegments) method to
"partially optimize" an index down to maxNumSegments segments.
(Mike McCandless)
9. LUCENE-1080: Changed Token.DEFAULT_TYPE to be public.
10. LUCENE-1064: Changed TopDocs constructor to be public.
(Shai Erera via Michael Busch)
11. LUCENE-1079: DocValues cleanup: constructor now has no params,
and getInnerArray() now throws UnsupportedOperationException (Doron Cohen)
12. LUCENE-1089: Added PriorityQueue.insertWithOverflow, which returns
the Object (if any) that was bumped from the queue to allow
re-use. (Shai Erera via Mike McCandless)
13. LUCENE-1101: Token reuse 'contract' (defined LUCENE-969)
modified so it is token producer's responsibility
to call Token.clear(). (Doron Cohen)
14. LUCENE-1118: Changed StandardAnalyzer to skip too-long (default >
255 characters) tokens. You can increase this limit by calling
StandardAnalyzer.setMaxTokenLength(...). (Michael McCandless)
Bug fixes
1. LUCENE-933: QueryParser fixed to not produce empty sub
BooleanQueries "()" even if the Analyzer produced no
tokens for input. (Doron Cohen)
2. LUCENE-955: Fixed SegmentTermPositions to work correctly with the
first term in the dictionary. (Michael Busch)
3. LUCENE-951: Fixed NullPointerException in MultiLevelSkipListReader
that was thrown after a call of TermPositions.seek().
(Rich Johnson via Michael Busch)
4. LUCENE-938: Fixed cases where an unhandled exception in
IndexWriter's methods could cause deletes to be lost.
(Steven Parkes via Mike McCandless)
5. LUCENE-962: Fixed case where an unhandled exception in
IndexWriter.addDocument or IndexWriter.updateDocument could cause
unreferenced files in the index to not be deleted
(Steven Parkes via Mike McCandless)
6. LUCENE-957: RAMDirectory fixed to properly handle directories
larger than Integer.MAX_VALUE. (Doron Cohen)
7. LUCENE-781: MultiReader fixed to not throw NPE if isCurrent(),
isOptimized() or getVersion() is called. Separated MultiReader
into two classes: MultiSegmentReader extends IndexReader, is
package-protected and is created automatically by IndexReader.open()
in case the index has multiple segments. The public MultiReader
now extends MultiSegmentReader and is intended to be used by users
who want to add their own subreaders. (Daniel Naber, Michael Busch)
8. LUCENE-970: FilterIndexReader now implements isOptimized(). Before
a call of isOptimized() would throw a NPE. (Michael Busch)
9. LUCENE-832: ParallelReader fixed to not throw NPE if isCurrent(),
isOptimized() or getVersion() is called. (Michael Busch)
10. LUCENE-948: Fix FNFE exception caused by stale NFS client
directory listing caches when writers on different machines are
sharing an index over NFS and using a custom deletion policy (Mike
McCandless)
11. LUCENE-978: Ensure TermInfosReader, FieldsReader, and FieldsReader
close any streams they had opened if an exception is hit in the
constructor. (Ning Li via Mike McCandless)
12. LUCENE-985: If an extremely long term is in a doc (> 16383 chars),
we now throw an IllegalArgumentException saying the term is too
long, instead of cryptic ArrayIndexOutOfBoundsException. (Karl
Wettin via Mike McCandless)
13. LUCENE-991: The explain() method of BoostingTermQuery had errors
when no payloads were present on a document. (Peter Keegan via
Grant Ingersoll)
14. LUCENE-992: Fixed IndexWriter.updateDocument to be atomic again
(this was broken by LUCENE-843). (Ning Li via Mike McCandless)
15. LUCENE-1008: Fixed corruption case when document with no term
vector fields is added after documents with term vector fields.
This bug was introduced with LUCENE-843. (Grant Ingersoll via
Mike McCandless)
16. LUCENE-1006: Fixed QueryParser to accept a "" field value (zero
length quoted string.) (yonik)
17. LUCENE-1010: Fixed corruption case when document with no term
vector fields is added after documents with term vector fields.
This case is hit during merge and would cause an EOFException.
This bug was introduced with LUCENE-984. (Andi Vajda via Mike
McCandless)
19. LUCENE-1009: Fix merge slowdown with LogByteSizeMergePolicy when
autoCommit=false and documents are using stored fields and/or term
vectors. (Mark Miller via Mike McCandless)
20. LUCENE-1011: Fixed corruption case when two or more machines,
sharing an index over NFS, can be writers in quick succession.
(Patrick Kimber via Mike McCandless)
21. LUCENE-1028: Fixed Weight serialization for few queries:
DisjunctionMaxQuery, ValueSourceQuery, CustomScoreQuery.
Serialization check added for all queries.
(Kyle Maxwell via Doron Cohen)
22. LUCENE-1048: Fixed incorrect behavior in Lock.obtain(...) when the
timeout argument is very large (eg Long.MAX_VALUE). Also added
Lock.LOCK_OBTAIN_WAIT_FOREVER constant to never timeout. (Nikolay
Diakov via Mike McCandless)
23. LUCENE-1050: Throw LockReleaseFailedException in
Simple/NativeFSLockFactory if we fail to delete the lock file when
releasing the lock. (Nikolay Diakov via Mike McCandless)
24. LUCENE-1071: Fixed SegmentMerger to correctly set payload bit in
the merged segment. (Michael Busch)
25. LUCENE-1042: Remove throwing of IOException in getTermFreqVector(int, String, TermVectorMapper) to be consistent
with other getTermFreqVector calls. Also removed the throwing of the other IOException in that method to be consistent. (Karl Wettin via Grant Ingersoll)
26. LUCENE-1096: Fixed Hits behavior when hits' docs are deleted
along with iterating the hits. Deleting docs already retrieved
now works seamlessly. If docs not yet retrieved are deleted
(e.g. from another thread), and then, relying on the initial
Hits.length(), an application attempts to retrieve more hits
than actually exist , a ConcurrentMidificationException
is thrown. (Doron Cohen)
27. LUCENE-1068: Changed StandardTokenizer to fix an issue with it marking
the type of some tokens incorrectly. This is done by adding a new flag named
replaceInvalidAcronym which defaults to false, the current, incorrect behavior. Setting
this flag to true fixes the problem. This flag is a temporary fix and is already
marked as being deprecated. 3.x will implement the correct approach. (Shai Erera via Grant Ingersoll)
LUCENE-1140: Fixed NPE caused by 1068 (Alexei Dets via Grant Ingersoll)
28. LUCENE-749: ChainedFilter behavior fixed when logic of
first filter is ANDNOT. (Antonio Bruno via Doron Cohen)
29. LUCENE-508: Make sure SegmentTermEnum.prev() is accurate (= last
term) after next() returns false. (Steven Tamm via Mike
McCandless)
New features
1. LUCENE-906: Elision filter for French.
(Mathieu Lecarme via Otis Gospodnetic)
2. LUCENE-960: Added a SpanQueryFilter and related classes to allow for
not only filtering, but knowing where in a Document a Filter matches
(Grant Ingersoll)
3. LUCENE-868: Added new Term Vector access features. New callback
mechanism allows application to define how and where to read Term
Vectors from disk. This implementation contains several extensions
of the new abstract TermVectorMapper class. The new API should be
back-compatible. No changes in the actual storage of Term Vectors
has taken place.
3.1 LUCENE-1038: Added setDocumentNumber() method to TermVectorMapper
to provide information about what document is being accessed.
(Karl Wettin via Grant Ingersoll)
4. LUCENE-975: Added PositionBasedTermVectorMapper that allows for
position based lookup of term vector information.
See item #3 above (LUCENE-868).
5. LUCENE-1011: Added simple tools (all in org.apache.lucene.store)
to verify that locking is working properly. LockVerifyServer runs
a separate server to verify locks. LockStressTest runs a simple
tool that rapidly obtains and releases locks.
VerifyingLockFactory is a LockFactory that wraps any other
LockFactory and consults the LockVerifyServer whenever a lock is
obtained or released, throwing an exception if an illegal lock
obtain occurred. (Patrick Kimber via Mike McCandless)
6. LUCENE-1015: Added FieldCache extension (ExtendedFieldCache) to
support doubles and longs. Added support into SortField for sorting
on doubles and longs as well. (Grant Ingersoll)
7. LUCENE-1020: Created basic index checking & repair tool
(o.a.l.index.CheckIndex). When run without -fix it does a
detailed test of all segments in the index and reports summary
information and any errors it hit. With -fix it will remove
segments that had errors. (Mike McCandless)
8. LUCENE-743: Add IndexReader.reopen() method that re-opens an
existing IndexReader by only loading those portions of an index
that have changed since the reader was (re)opened. reopen() can
be significantly faster than open(), depending on the amount of
index changes. SegmentReader, MultiSegmentReader, MultiReader,
and ParallelReader implement reopen(). (Michael Busch)
9. LUCENE-1040: CharArraySet useful for efficiently checking
set membership of text specified by char[]. (yonik)
10. LUCENE-1073: Created SnapshotDeletionPolicy to facilitate taking a
live backup of an index without pausing indexing. (Mike
McCandless)
11. LUCENE-1019: CustomScoreQuery enhanced to support multiple
ValueSource queries. (Kyle Maxwell via Doron Cohen)
12. LUCENE-1095: Added an option to StopFilter to increase
positionIncrement of the token succeeding a stopped token.
Disabled by default. Similar option added to QueryParser
to consider token positions when creating PhraseQuery
and MultiPhraseQuery. Disabled by default (so by default
the query parser ignores position increments).
(Doron Cohen)
13. LUCENE-1380: Added TokenFilter for setting position increment in special cases related to the ShingleFilter (Mck SembWever, Steve Rowe, Karl Wettin via Grant Ingersoll)
Optimizations
1. LUCENE-937: CachingTokenFilter now uses an iterator to access the
Tokens that are cached in the LinkedList. This increases performance
significantly, especially when the number of Tokens is large.
(Mark Miller via Michael Busch)
2. LUCENE-843: Substantial optimizations to improve how IndexWriter
uses RAM for buffering documents and to speed up indexing (2X-8X
faster). A single shared hash table now records the in-memory
postings per unique term and is directly flushed into a single
segment. (Mike McCandless)
3. LUCENE-892: Fixed extra "buffer to buffer copy" that sometimes
takes place when using compound files. (Mike McCandless)
4. LUCENE-959: Remove synchronization in Document (yonik)
5. LUCENE-963: Add setters to Field to allow for re-using a single
Field instance during indexing. This is a sizable performance
gain, especially for small documents. (Mike McCandless)
6. LUCENE-939: Check explicitly for boundary conditions in FieldInfos
and don't rely on exceptions. (Michael Busch)
7. LUCENE-966: Very substantial speedups (~6X faster) for
StandardTokenizer (StandardAnalyzer) by using JFlex instead of
JavaCC to generate the tokenizer.
(Stanislaw Osinski via Mike McCandless)
8. LUCENE-969: Changed core tokenizers & filters to re-use Token and
TokenStream instances when possible to improve tokenization
performance (~10-15%). (Mike McCandless)
9. LUCENE-871: Speedup ISOLatin1AccentFilter (Ian Boston via Mike
McCandless)
10. LUCENE-986: Refactored SegmentInfos from IndexReader into the new
subclass DirectoryIndexReader. SegmentReader and MultiSegmentReader
now extend DirectoryIndexReader and are the only IndexReader
implementations that use SegmentInfos to access an index and
acquire a write lock for index modifications. (Michael Busch)
11. LUCENE-1007: Allow flushing in IndexWriter to be triggered by
either RAM usage or document count or both (whichever comes
first), by adding symbolic constant DISABLE_AUTO_FLUSH to disable
one of the flush triggers. (Ning Li via Mike McCandless)
12. LUCENE-1043: Speed up merging of stored fields by bulk-copying the
raw bytes for each contiguous range of non-deleted documents.
(Robert Engels via Mike McCandless)
13. LUCENE-693: Speed up nested conjunctions (~2x) that match many
documents, and a slight performance increase for top level
conjunctions. (yonik)
14. LUCENE-1098: Make inner class StandardAnalyzer.SavedStreams static
and final. (Nathan Beyer via Michael Busch)
Documentation
1. LUCENE-1051: Generate separate javadocs for core, demo and contrib
classes, as well as an unified view. Also add an appropriate menu
structure to the website. (Michael Busch)
2. LUCENE-746: Fix error message in AnalyzingQueryParser.getPrefixQuery.
(Ronnie Kolehmainen via Michael Busch)
Build
1. LUCENE-908: Improvements and simplifications for how the MANIFEST
file and the META-INF dir are created. (Michael Busch)
2. LUCENE-935: Various improvements for the maven artifacts. Now the
artifacts also include the sources as .jar files. (Michael Busch)
3. Added apply-patch target to top-level build. Defaults to looking for
a patch in ${basedir}/../patches with name specified by -Dpatch.name.
Can also specify any location by -Dpatch.file property on the command
line. This should be helpful for easy application of patches, but it
is also a step towards integrating automatic patch application with
JIRA and Hudson, and is thus subject to change. (Grant Ingersoll)
4. LUCENE-935: Defined property "m2.repository.url" to allow setting
the url to a maven remote repository to deploy to. (Michael Busch)
5. LUCENE-1051: Include javadocs in the maven artifacts. (Michael Busch)
6. LUCENE-1055: Remove gdata-server from build files and its sources
from trunk. (Michael Busch)
7. LUCENE-935: Allow to deploy maven artifacts to a remote m2 repository
via scp and ssh authentication. (Michael Busch)
8. LUCENE-1123: Allow overriding the specification version for
MANIFEST.MF (Michael Busch)
Test Cases
1. LUCENE-766: Test adding two fields with the same name but different
term vector setting. (Nicolas Lalevée via Doron Cohen)
======================= Release 2.2.0 2007-06-19 =======================
Changes in runtime behavior
API Changes
1. LUCENE-793: created new exceptions and added them to throws clause
for many methods (all subclasses of IOException for backwards
compatibility): index.StaleReaderException,
index.CorruptIndexException, store.LockObtainFailedException.
This was done to better call out the possible root causes of an
IOException from these methods. (Mike McCandless)
2. LUCENE-811: make SegmentInfos class, plus a few methods from related
classes, package-private again (they were unnecessarily made public
as part of LUCENE-701). (Mike McCandless)
3. LUCENE-710: added optional autoCommit boolean to IndexWriter
constructors. When this is false, index changes are not committed
until the writer is closed. This gives explicit control over when
a reader will see the changes. Also added optional custom
deletion policy to explicitly control when prior commits are
removed from the index. This is intended to allow applications to
share an index over NFS by customizing when prior commits are
deleted. (Mike McCandless)
4. LUCENE-818: changed most public methods of IndexWriter,
IndexReader (and its subclasses), FieldsReader and RAMDirectory to
throw AlreadyClosedException if they are accessed after being
closed. (Mike McCandless)
5. LUCENE-834: Changed some access levels for certain Span classes to allow them
to be overridden. They have been marked expert only and not for public
consumption. (Grant Ingersoll)
6. LUCENE-796: Removed calls to super.* from various get*Query methods in
MultiFieldQueryParser, in order to allow sub-classes to override them.
(Steven Parkes via Otis Gospodnetic)
7. LUCENE-857: Removed caching from QueryFilter and deprecated QueryFilter
in favour of QueryWrapperFilter or QueryWrapperFilter + CachingWrapperFilter
combination when caching is desired.
(Chris Hostetter, Otis Gospodnetic)
8. LUCENE-869: Changed FSIndexInput and FSIndexOutput to inner classes of FSDirectory
to enable extensibility of these classes. (Michael Busch)
9. LUCENE-580: Added the public method reset() to TokenStream. This method does
nothing by default, but may be overwritten by subclasses to support consuming
the TokenStream more than once. (Michael Busch)
10. LUCENE-580: Added a new constructor to Field that takes a TokenStream as
argument, available as tokenStreamValue(). This is useful to avoid the need of
"dummy analyzers" for pre-analyzed fields. (Karl Wettin, Michael Busch)
11. LUCENE-730: Added the new methods to BooleanQuery setAllowDocsOutOfOrder() and
getAllowDocsOutOfOrder(). Deprecated the methods setUseScorer14() and
getUseScorer14(). The optimization patch LUCENE-730 (see Optimizations->3.)
improves performance for certain queries but results in scoring out of docid
order. This patch reverse this change, so now by default hit docs are scored
in docid order if not setAllowDocsOutOfOrder(true) is explicitly called.
This patch also enables the tests in QueryUtils again that check for docid
order. (Paul Elschot, Doron Cohen, Michael Busch)
12. LUCENE-888: Added Directory.openInput(File path, int bufferSize)
to optionally specify the size of the read buffer. Also added
BufferedIndexInput.setBufferSize(int) to change the buffer size.
(Mike McCandless)
13. LUCENE-923: Make SegmentTermPositionVector package-private. It does not need
to be public because it implements the public interface TermPositionVector.
(Michael Busch)
Bug fixes
1. LUCENE-804: Fixed build.xml to pack a fully compilable src dist. (Doron Cohen)
2. LUCENE-813: Leading wildcard fixed to work with trailing wildcard.
Query parser modified to create a prefix query only for the case
that there is a single trailing wildcard (and no additional wildcard
or '?' in the query text). (Doron Cohen)
3. LUCENE-812: Add no-argument constructors to NativeFSLockFactory
and SimpleFSLockFactory. This enables all 4 builtin LockFactory
implementations to be specified via the System property
org.apache.lucene.store.FSDirectoryLockFactoryClass. (Mike McCandless)
4. LUCENE-821: The new single-norm-file introduced by LUCENE-756
failed to reduce the number of open descriptors since it was still
opened once per field with norms. (yonik)
5. LUCENE-823: Make sure internal file handles are closed when
hitting an exception (eg disk full) while flushing deletes in
IndexWriter's mergeSegments, and also during
IndexWriter.addIndexes. (Mike McCandless)
6. LUCENE-825: If directory is removed after
FSDirectory.getDirectory() but before IndexReader.open you now get
a FileNotFoundException like Lucene pre-2.1 (before this fix you
got an NPE). (Mike McCandless)
7. LUCENE-800: Removed backslash from the TERM_CHAR list in the queryparser,
because the backslash is the escape character. Also changed the ESCAPED_CHAR
list to contain all possible characters, because every character that
follows a backslash should be considered as escaped. (Michael Busch)
8. LUCENE-372: QueryParser.parse() now ensures that the entire input string
is consumed. Now a ParseException is thrown if a query contains too many
closing parentheses. (Andreas Neumann via Michael Busch)
9. LUCENE-814: javacc build targets now fix line-end-style of generated files.
Now also deleting all javacc generated files before calling javacc.
(Steven Parkes, Doron Cohen)
10. LUCENE-829: close readers in contrib/benchmark. (Karl Wettin, Doron Cohen)
11. LUCENE-828: Minor fix for Term's equal().
(Paul Cowan via Otis Gospodnetic)
12. LUCENE-846: Fixed: if IndexWriter is opened with autoCommit=false,
and you call addIndexes, and hit an exception (eg disk full) then
when IndexWriter rolls back its internal state this could corrupt
the instance of IndexWriter (but, not the index itself) by
referencing already deleted segments. This bug was only present
in 2.2 (trunk), ie was never released. (Mike McCandless)
13. LUCENE-736: Sloppy phrase query with repeating terms matches wrong docs.
For example query "B C B"~2 matches the doc "A B C D E". (Doron Cohen)
14. LUCENE-789: Fixed: custom similarity is ignored when using MultiSearcher (problem reported
by Alexey Lef). Now the similarity applied by MultiSearcer.setSimilarity(sim) is being used.
Note that as before this fix, creating a multiSearcher from Searchers for whom custom similarity
was set has no effect - it is masked by the similarity of the MultiSearcher. This is as
designed, because MultiSearcher operates on Searchables (not Searchers). (Doron Cohen)
15. LUCENE-880: Fixed DocumentWriter to close the TokenStreams after it
has written the postings. Then the resources associated with the
TokenStreams can safely be released. (Michael Busch)
16. LUCENE-883: consecutive calls to Spellchecker.indexDictionary()
won't insert terms twice anymore. (Daniel Naber)
17. LUCENE-881: QueryParser.escape() now also escapes the characters
'|' and '&' which are part of the queryparser syntax. (Michael Busch)
18. LUCENE-886: Spellchecker clean up: exceptions aren't printed to STDERR
anymore and ignored, but re-thrown. Some javadoc improvements.
(Daniel Naber)
19. LUCENE-698: FilteredQuery now takes the query boost into account for
scoring. (Michael Busch)
20. LUCENE-763: Spellchecker: LuceneDictionary used to skip first word in
enumeration. (Christian Mallwitz via Daniel Naber)
21. LUCENE-903: FilteredQuery explanation inaccuracy with boost.
Explanation tests now "deep" check the explanation details.
(Chris Hostetter, Doron Cohen)
22. LUCENE-912: DisjunctionMaxScorer first skipTo(target) call ignores the
skip target param and ends up at the first match.
(Sudaakeran B. via Chris Hostetter & Doron Cohen)
23. LUCENE-913: Two consecutive score() calls return different
scores for Boolean Queries. (Michael Busch, Doron Cohen)
24. LUCENE-1013: Fix IndexWriter.setMaxMergeDocs to work "out of the
box", again, by moving set/getMaxMergeDocs up from
LogDocMergePolicy into LogMergePolicy. This fixes the API
breakage (non backwards compatible change) caused by LUCENE-994.
(Yonik Seeley via Mike McCandless)
New features
1. LUCENE-759: Added two n-gram-producing TokenFilters.
(Otis Gospodnetic)
2. LUCENE-822: Added FieldSelector capabilities to Searchable for use with
RemoteSearcher, and other Searchable implementations. (Mark Miller, Grant Ingersoll)
3. LUCENE-755: Added the ability to store arbitrary binary metadata in the posting list.
These metadata are called Payloads. For every position of a Token one Payload in the form
of a variable length byte array can be stored in the prox file.
Remark: The APIs introduced with this feature are in experimental state and thus
contain appropriate warnings in the javadocs.
(Michael Busch)
4. LUCENE-834: Added BoostingTermQuery which can boost scores based on the
values of a payload (see #3 above.) (Grant Ingersoll)
5. LUCENE-834: Similarity has a new method for scoring payloads called
scorePayloads that can be overridden to take advantage of payload
storage (see #3 above)
6. LUCENE-834: Added isPayloadAvailable() onto TermPositions interface and
implemented it in the appropriate places (Grant Ingersoll)
7. LUCENE-853: Added RemoteCachingWrapperFilter to enable caching of Filters
on the remote side of the RMI connection.
(Matt Ericson via Otis Gospodnetic)
8. LUCENE-446: Added Solr's search.function for scores based on field
values, plus CustomScoreQuery for simple score (post) customization.
(Yonik Seeley, Doron Cohen)
9. LUCENE-1058: Added new TeeTokenFilter (like the UNIX 'tee' command) and SinkTokenizer which can be used to share tokens between two or more
Fields such that the other Fields do not have to go through the whole Analysis process over again. For instance, if you have two
Fields that share all the same analysis steps except one lowercases tokens and the other does not, you can coordinate the operations
between the two using the TeeTokenFilter and the SinkTokenizer. See TeeSinkTokenTest.java for examples.
(Grant Ingersoll, Michael Busch, Yonik Seeley)
Optimizations
1. LUCENE-761: The proxStream is now cloned lazily in SegmentTermPositions
when nextPosition() is called for the first time. This allows using instances
of SegmentTermPositions instead of SegmentTermDocs without additional costs.
(Michael Busch)
2. LUCENE-431: RAMInputStream and RAMOutputStream extend IndexInput and
IndexOutput directly now. This avoids further buffering and thus avoids
unnecessary array copies. (Michael Busch)
3. LUCENE-730: Updated BooleanScorer2 to make use of BooleanScorer in some
cases and possibly improve scoring performance. Documents can now be
delivered out-of-order as they are scored (e.g. to HitCollector).
N.B. A bit of code had to be disabled in QueryUtils in order for
TestBoolean2 test to keep passing.
(Paul Elschot via Otis Gospodnetic)
4. LUCENE-882: Spellchecker doesn't store the ngrams anymore but only indexes
them to keep the spell index small. (Daniel Naber)
5. LUCENE-430: Delay allocation of the buffer after a clone of BufferedIndexInput.
Together with LUCENE-888 this will allow to adjust the buffer size
dynamically. (Paul Elschot, Michael Busch)
6. LUCENE-888: Increase buffer sizes inside CompoundFileWriter and
BufferedIndexOutput. Also increase buffer size in
BufferedIndexInput, but only when used during merging. Together,
these increases yield 10-18% overall performance gain vs the
previous 1K defaults. (Mike McCandless)
7. LUCENE-866: Adds multi-level skip lists to the posting lists. This speeds
up most queries that use skipTo(), especially on big indexes with large posting
lists. For average AND queries the speedup is about 20%, for queries that
contain very frequent and very unique terms the speedup can be over 80%.
(Michael Busch)
Documentation
1. LUCENE 791 && INFRA-1173: Infrastructure moved the Wiki to
http://wiki.apache.org/lucene-java/ Updated the links in the docs and
wherever else I found references. (Grant Ingersoll, Joe Schaefer)
2. LUCENE-807: Fixed the javadoc for ScoreDocComparator.compare() to be
consistent with java.util.Comparator.compare(): Any integer is allowed to
be returned instead of only -1/0/1.
(Paul Cowan via Michael Busch)
3. LUCENE-875: Solved javadoc warnings & errors under jdk1.4.
Solved javadoc errors under jdk5 (jars in path for gdata).
Made "javadocs" target depend on "build-contrib" for first downloading
contrib jars configured for dynamic downloaded. (Note: when running
behind firewall, a firewall prompt might pop up) (Doron Cohen)
4. LUCENE-740: Added SNOWBALL-LICENSE.txt to the snowball package and a
remark about the license to NOTICE.TXT. (Steven Parkes via Michael Busch)
5. LUCENE-925: Added analysis package javadocs. (Grant Ingersoll and Doron Cohen)
6. LUCENE-926: Added document package javadocs. (Grant Ingersoll)
Build
1. LUCENE-802: Added LICENSE.TXT and NOTICE.TXT to Lucene jars.
(Steven Parkes via Michael Busch)
2. LUCENE-885: "ant test" now includes all contrib tests. The new
"ant test-core" target can be used to run only the Core (non
contrib) tests.
(Chris Hostetter)
3. LUCENE-900: "ant test" now enables Java assertions (in Lucene packages).
(Doron Cohen)
4. LUCENE-894: Add custom build file for binary distributions that includes
targets to build the demos. (Chris Hostetter, Michael Busch)
5. LUCENE-904: The "package" targets in build.xml now also generate .md5
checksum files. (Chris Hostetter, Michael Busch)
6. LUCENE-907: Include LICENSE.TXT and NOTICE.TXT in the META-INF dirs of
demo war, demo jar, and the contrib jars. (Michael Busch)
7. LUCENE-909: Demo targets for running the demo. (Doron Cohen)
8. LUCENE-908: Improves content of MANIFEST file and makes it customizable
for the contribs. Adds SNOWBALL-LICENSE.txt to META-INF of the snowball
jar and makes sure that the lucli jar contains LICENSE.txt and NOTICE.txt.
(Chris Hostetter, Michael Busch)
9. LUCENE-930: Various contrib building improvements to ensure contrib
dependencies are met, and test compilation errors fail the build.
(Steven Parkes, Chris Hostetter)
10. LUCENE-622: Add ant target and pom.xml files for building maven artifacts
of the Lucene core and the contrib modules.
(Sami Siren, Karl Wettin, Michael Busch)
======================= Release 2.1.0 2007-02-14 =======================
Changes in runtime behavior
1. 's' and 't' have been removed from the list of default stopwords
in StopAnalyzer (also used in by StandardAnalyzer). Having e.g. 's'
as a stopword meant that 's-class' led to the same results as 'class'.
Note that this problem still exists for 'a', e.g. in 'a-class' as
'a' continues to be a stopword.
(Daniel Naber)
2. LUCENE-478: Updated the list of Unicode code point ranges for CJK
(now split into CJ and K) in StandardAnalyzer. (John Wang and
Steven Rowe via Otis Gospodnetic)
3. Modified some CJK Unicode code point ranges in StandardTokenizer.jj,
and added a few more of them to increase CJK character coverage.
Also documented some of the ranges.
(Otis Gospodnetic)
4. LUCENE-489: Add support for leading wildcard characters (*, ?) to
QueryParser. Default is to disallow them, as before.
(Steven Parkes via Otis Gospodnetic)
5. LUCENE-703: QueryParser changed to default to use of ConstantScoreRangeQuery
for range queries. Added useOldRangeQuery property to QueryParser to allow
selection of old RangeQuery class if required.
(Mark Harwood)
6. LUCENE-543: WildcardQuery now performs a TermQuery if the provided term
does not contain a wildcard character (? or *), when previously a
StringIndexOutOfBoundsException was thrown.
(Michael Busch via Erik Hatcher)
7. LUCENE-726: Removed the use of deprecated doc.fields() method and
Enumeration.
(Michael Busch via Otis Gospodnetic)
8. LUCENE-436: Removed finalize() in TermInfosReader and SegmentReader,
and added a call to enumerators.remove() in TermInfosReader.close().
The finalize() overrides were added to help with a pre-1.4.2 JVM bug
that has since been fixed, plus we no longer support pre-1.4.2 JVMs.
(Otis Gospodnetic)
9. LUCENE-771: The default location of the write lock is now the
index directory, and is named simply "write.lock" (without a big
digest prefix). The system properties "org.apache.lucene.lockDir"
nor "java.io.tmpdir" are no longer used as the global directory
for storing lock files, and the LOCK_DIR field of FSDirectory is
now deprecated. (Mike McCandless)
New features
1. LUCENE-503: New ThaiAnalyzer and ThaiWordFilter in contrib/analyzers
(Samphan Raruenrom via Chris Hostetter)
2. LUCENE-545: New FieldSelector API and associated changes to
IndexReader and implementations. New Fieldable interface for use
with the lazy field loading mechanism. (Grant Ingersoll and Chuck
Williams via Grant Ingersoll)
3. LUCENE-676: Move Solr's PrefixFilter to Lucene core. (Yura
Smolsky, Yonik Seeley)
4. LUCENE-678: Added NativeFSLockFactory, which implements locking
using OS native locking (via java.nio.*). (Michael McCandless via
Yonik Seeley)
5. LUCENE-544: Added the ability to specify different boosts for
different fields when using MultiFieldQueryParser (Matt Ericson
via Otis Gospodnetic)
6. LUCENE-528: New IndexWriter.addIndexesNoOptimize() that doesn't
optimize the index when adding new segments, only performing
merges as needed. (Ning Li via Yonik Seeley)
7. LUCENE-573: QueryParser now allows backslash escaping in
quoted terms and phrases. (Michael Busch via Yonik Seeley)
8. LUCENE-716: QueryParser now allows specification of Unicode
characters in terms via a unicode escape of the form \uXXXX
(Michael Busch via Yonik Seeley)
9. LUCENE-709: Added RAMDirectory.sizeInBytes(), IndexWriter.ramSizeInBytes()
and IndexWriter.flushRamSegments(), allowing applications to
control the amount of memory used to buffer documents.
(Chuck Williams via Yonik Seeley)
10. LUCENE-723: QueryParser now parses *:* as MatchAllDocsQuery
(Yonik Seeley)
11. LUCENE-741: Command-line utility for modifying or removing norms
on fields in an existing index. This is mostly based on LUCENE-496
and lives in contrib/miscellaneous.
(Chris Hostetter, Otis Gospodnetic)
12. LUCENE-759: Added NGramTokenizer and EdgeNGramTokenizer classes and
their passing unit tests.
(Otis Gospodnetic)
13. LUCENE-565: Added methods to IndexWriter to more efficiently
handle updating documents (the "delete then add" use case). This
is intended to be an eventual replacement for the existing
IndexModifier. Added IndexWriter.flush() (renamed from
flushRamSegments()) to flush all pending updates (held in RAM), to
the Directory. (Ning Li via Mike McCandless)
14. LUCENE-762: Added in SIZE and SIZE_AND_BREAK FieldSelectorResult options
which allow one to retrieve the size of a field without retrieving the
actual field. (Chuck Williams via Grant Ingersoll)
15. LUCENE-799: Properly handle lazy, compressed fields.
(Mike Klaas via Grant Ingersoll)
API Changes
1. LUCENE-438: Remove "final" from Token, implement Cloneable, allow
changing of termText via setTermText(). (Yonik Seeley)
2. org.apache.lucene.analysis.nl.WordlistLoader has been deprecated
and is supposed to be replaced with the WordlistLoader class in
package org.apache.lucene.analysis (Daniel Naber)
3. LUCENE-609: Revert return type of Document.getField(s) to Field
for backward compatibility, added new Document.getFieldable(s)
for access to new lazy loaded fields. (Yonik Seeley)
4. LUCENE-608: Document.fields() has been deprecated and a new method
Document.getFields() has been added that returns a List instead of
an Enumeration (Daniel Naber)
5. LUCENE-605: New Explanation.isMatch() method and new ComplexExplanation
subclass allows explain methods to produce Explanations which model
"matching" independent of having a positive value.
(Chris Hostetter)
6. LUCENE-621: New static methods IndexWriter.setDefaultWriteLockTimeout
and IndexWriter.setDefaultCommitLockTimeout for overriding default
timeout values for all future instances of IndexWriter (as well
as for any other classes that may reference the static values,
ie: IndexReader).
(Michael McCandless via Chris Hostetter)
7. LUCENE-638: FSDirectory.list() now only returns the directory's
Lucene-related files. Thanks to this change one can now construct
a RAMDirectory from a file system directory that contains files
not related to Lucene.
(Simon Willnauer via Daniel Naber)
8. LUCENE-635: Decoupling locking implementation from Directory
implementation. Added set/getLockFactory to Directory and moved
all locking code into subclasses of abstract class LockFactory.
FSDirectory and RAMDirectory still default to their prior locking
implementations, but now you can mix & match, for example using
SingleInstanceLockFactory (ie, in memory locking) locking with an
FSDirectory. Note that now you must call setDisableLocks before
the instantiation a FSDirectory if you wish to disable locking
for that Directory.
(Michael McCandless, Jeff Patterson via Yonik Seeley)
9. LUCENE-657: Made FuzzyQuery non-final and inner ScoreTerm protected.
(Steven Parkes via Otis Gospodnetic)
10. LUCENE-701: Lockless commits: a commit lock is no longer required
when a writer commits and a reader opens the index. This includes
a change to the index file format (see docs/fileformats.html for
details). It also removes all APIs associated with the commit
lock & its timeout. Readers are now truly read-only and do not
block one another on startup. This is the first step to getting
Lucene to work correctly over NFS (second step is
LUCENE-710). (Mike McCandless)
11. LUCENE-722: DEFAULT_MIN_DOC_FREQ was misspelled DEFALT_MIN_DOC_FREQ
in Similarity's MoreLikeThis class. The misspelling has been
replaced by the correct spelling.
(Andi Vajda via Daniel Naber)
12. LUCENE-738: Reduce the size of the file that keeps track of which
documents are deleted when the number of deleted documents is
small. This changes the index file format and cannot be
read by previous versions of Lucene. (Doron Cohen via Yonik Seeley)
13. LUCENE-756: Maintain all norms in a single .nrm file to reduce the
number of open files and file descriptors for the non-compound index
format. This changes the index file format, but maintains the
ability to read and update older indices. The first segment merge
on an older format index will create a single .nrm file for the new
segment. (Doron Cohen via Yonik Seeley)
14. LUCENE-732: DateTools support has been added to QueryParser, with
setters for both the default Resolution, and per-field Resolution.
For backwards compatibility, DateField is still used if no Resolutions
are specified. (Michael Busch via Chris Hostetter)
15. Added isOptimized() method to IndexReader.
(Otis Gospodnetic)
16. LUCENE-773: Deprecate the FSDirectory.getDirectory(*) methods that
take a boolean "create" argument. Instead you should use
IndexWriter's "create" argument to create a new index.
(Mike McCandless)
17. LUCENE-780: Add a static Directory.copy() method to copy files
from one Directory to another. (Jiri Kuhn via Mike McCandless)
18. LUCENE-773: Added Directory.clearLock(String name) to forcefully
remove an old lock. The default implementation is to ask the
lockFactory (if non null) to clear the lock. (Mike McCandless)
19. LUCENE-795: Directory.renameFile() has been deprecated as it is
not used anymore inside Lucene. (Daniel Naber)
Bug fixes
1. Fixed the web application demo (built with "ant war-demo") which
didn't work because it used a QueryParser method that had
been removed (Daniel Naber)
2. LUCENE-583: ISOLatin1AccentFilter fails to preserve positionIncrement
(Yonik Seeley)
3. LUCENE-575: SpellChecker min score is incorrectly changed by suggestSimilar
(Karl Wettin via Yonik Seeley)
4. LUCENE-587: Explanation.toHtml was producing malformed HTML
(Chris Hostetter)
5. Fix to allow MatchAllDocsQuery to be used with RemoteSearcher (Yonik Seeley)
6. LUCENE-601: RAMDirectory and RAMFile made Serializable
(Karl Wettin via Otis Gospodnetic)
7. LUCENE-557: Fixes to BooleanQuery and FilteredQuery so that the score
Explanations match up with the real scores.
(Chris Hostetter)
8. LUCENE-607: ParallelReader's TermEnum fails to advance properly to
new fields (Chuck Williams, Christian Kohlschuetter via Yonik Seeley)
9. LUCENE-610,LUCENE-611: Simple syntax changes to allow compilation with ecj:
disambiguate inner class scorer's use of doc() in BooleanScorer2,
other test code changes. (DM Smith via Yonik Seeley)
10. LUCENE-451: All core query types now use ComplexExplanations so that
boosts of zero don't confuse the BooleanWeight explain method.
(Chris Hostetter)
11. LUCENE-593: Fixed LuceneDictionary's inner Iterator
(Kåre Fiedler Christiansen via Otis Gospodnetic)
12. LUCENE-641: fixed an off-by-one bug with IndexWriter.setMaxFieldLength()
(Daniel Naber)
13. LUCENE-659: Make PerFieldAnalyzerWrapper delegate getPositionIncrementGap()
to the correct analyzer for the field. (Chuck Williams via Yonik Seeley)
14. LUCENE-650: Fixed NPE in Locale specific String Sort when Document
has no value.
(Oliver Hutchison via Chris Hostetter)
15. LUCENE-683: Fixed data corruption when reading lazy loaded fields.
(Yonik Seeley)
16. LUCENE-678: Fixed bug in NativeFSLockFactory which caused the same
lock to be shared between different directories.
(Michael McCandless via Yonik Seeley)
17. LUCENE-690: Fixed thread unsafe use of IndexInput by lazy loaded fields.
(Yonik Seeley)
18. LUCENE-696: Fix bug when scorer for DisjunctionMaxQuery has skipTo()
called on it before next(). (Yonik Seeley)
19. LUCENE-569: Fixed SpanNearQuery bug, for 'inOrder' queries it would fail
to recognize ordered spans if they overlapped with unordered spans.
(Paul Elschot via Chris Hostetter)
20. LUCENE-706: Updated fileformats.xml|html concerning the docdelta value
in the frequency file. (Johan Stuyts, Doron Cohen via Grant Ingersoll)
21. LUCENE-715: Fixed private constructor in IndexWriter.java to
properly release the acquired write lock if there is an
IOException after acquiring the write lock but before finishing
instantiation. (Matthew Bogosian via Mike McCandless)
22. LUCENE-651: Multiple different threads requesting the same
FieldCache entry (often for Sorting by a field) at the same
time caused multiple generations of that entry, which was
detrimental to performance and memory use.
(Oliver Hutchison via Otis Gospodnetic)
23. LUCENE-717: Fixed build.xml not to fail when there is no lib dir.
(Doron Cohen via Otis Gospodnetic)
24. LUCENE-728: Removed duplicate/old MoreLikeThis and SimilarityQueries
classes from contrib/similarity, as their new home is under
contrib/queries.
(Otis Gospodnetic)
25. LUCENE-669: Do not double-close the RandomAccessFile in
FSIndexInput/Output during finalize(). Besides sending an
IOException up to the GC, this may also be the cause intermittent
"The handle is invalid" IOExceptions on Windows when trying to
close readers or writers. (Michael Busch via Mike McCandless)
26. LUCENE-702: Fix IndexWriter.addIndexes(*) to not corrupt the index
on any exceptions (eg disk full). The semantics of these methods
is now transactional: either all indices are merged or none are.
Also fixed IndexWriter.mergeSegments (called outside of
addIndexes(*) by addDocument, optimize, flushRamSegments) and
IndexReader.commit() (called by close) to clean up and keep the
instance state consistent to what's actually in the index (Mike
McCandless).
27. LUCENE-129: Change finalizers to do "try {...} finally
{super.finalize();}" to make sure we don't miss finalizers in
classes above us. (Esmond Pitt via Mike McCandless)
28. LUCENE-754: Fix a problem introduced by LUCENE-651, causing
IndexReaders to hang around forever, in addition to not
fixing the original FieldCache performance problem.
(Chris Hostetter, Yonik Seeley)
29. LUCENE-140: Fix IndexReader.deleteDocument(int docNum) to
correctly raise ArrayIndexOutOfBoundsException when docNum is too
large. Previously, if docNum was only slightly too large (within
the same multiple of 8, ie, up to 7 ints beyond maxDoc), no
exception would be raised and instead the index would become
silently corrupted. The corruption then only appears much later,
in mergeSegments, when the corrupted segment is merged with
segment(s) after it. (Mike McCandless)
30. LUCENE-768: Fix case where an Exception during deleteDocument,
undeleteAll or setNorm in IndexReader could leave the reader in a
state where close() fails to release the write lock.
(Mike McCandless)
31. Remove "tvp" from known index file extensions because it is
never used. (Nicolas Lalevée via Bernhard Messer)
32. LUCENE-767: Change how SegmentReader.maxDoc() is computed to not
rely on file length check and instead use the SegmentInfo's
docCount that's already stored explicitly in the index. This is a
defensive bug fix (ie, there is no known problem seen "in real
life" due to this, just a possible future problem). (Chuck
Williams via Mike McCandless)
Optimizations
1. LUCENE-586: TermDocs.skipTo() is now more efficient for
multi-segment indexes. This will improve the performance of many
types of queries against a non-optimized index. (Andrew Hudson
via Yonik Seeley)
2. LUCENE-623: RAMDirectory.close now nulls out its reference to all
internal "files", allowing them to be GCed even if references to the
RAMDirectory itself still exist. (Nadav Har'El via Chris Hostetter)
3. LUCENE-629: Compressed fields are no longer uncompressed and
recompressed during segment merges (e.g. during indexing or
optimizing), thus improving performance . (Michael Busch via Otis
Gospodnetic)
4. LUCENE-388: Improve indexing performance when maxBufferedDocs is
large by keeping a count of buffered documents rather than
counting after each document addition. (Doron Cohen, Paul Smith,
Yonik Seeley)
5. Modified TermScorer.explain to use TermDocs.skipTo() instead of
looping through docs. (Grant Ingersoll)
6. LUCENE-672: New indexing segment merge policy flushes all
buffered docs to their own segment and delays a merge until
mergeFactor segments of a certain level have been accumulated.
This increases indexing performance in the presence of deleted
docs or partially full segments as well as enabling future
optimizations.
NOTE: this also fixes an "under-merging" bug whereby it is
possible to get far too many segments in your index (which will
drastically slow down search, risks exhausting file descriptor
limit, etc.). This can happen when the number of buffered docs
at close, plus the number of docs in the last non-ram segment is
greater than mergeFactor. (Ning Li, Yonik Seeley)
7. Lazy loaded fields unnecessarily retained an extra copy of loaded
String data. (Yonik Seeley)
8. LUCENE-443: ConjunctionScorer performance increase. Speed up
any BooleanQuery with more than one mandatory clause.
(Abdul Chaudhry, Paul Elschot via Yonik Seeley)
9. LUCENE-365: DisjunctionSumScorer performance increase of
~30%. Speeds up queries with optional clauses. (Paul Elschot via
Yonik Seeley)
10. LUCENE-695: Optimized BufferedIndexInput.readBytes() for medium
size buffers, which will speed up merging and retrieving binary
and compressed fields. (Nadav Har'El via Yonik Seeley)
11. LUCENE-687: Lazy skipping on proximity file speeds up most
queries involving term positions, including phrase queries.
(Michael Busch via Yonik Seeley)
12. LUCENE-714: Replaced 2 cases of manual for-loop array copying
with calls to System.arraycopy instead, in DocumentWriter.java.
(Nicolas Lalevee via Mike McCandless)
13. LUCENE-729: Non-recursive skipTo and next implementation of
TermDocs for a MultiReader. The old implementation could
recurse up to the number of segments in the index. (Yonik Seeley)
14. LUCENE-739: Improve segment merging performance by reusing
the norm array across different fields and doing bulk writes
of norms of segments with no deleted docs.
(Michael Busch via Yonik Seeley)
15. LUCENE-745: Add BooleanQuery.clauses(), allowing direct access
to the List of clauses and replaced the internal synchronized Vector
with an unsynchronized List. (Yonik Seeley)
16. LUCENE-750: Remove finalizers from FSIndexOutput and move the
FSIndexInput finalizer to the actual file so all clones don't
register a new finalizer. (Yonik Seeley)
Test Cases
1. Added TestTermScorer.java (Grant Ingersoll)
2. Added TestWindowsMMap.java (Benson Margulies via Mike McCandless)
3. LUCENE-744 Append the user.name property onto the temporary directory
that is created so it doesn't interfere with other users. (Grant Ingersoll)
Documentation
1. Added style sheet to xdocs named lucene.css and included in the
Anakia VSL descriptor. (Grant Ingersoll)
2. Added scoring.xml document into xdocs. Updated Similarity.java
scoring formula.(Grant Ingersoll and Steve Rowe. Updates from:
Michael McCandless, Doron Cohen, Chris Hostetter, Doug Cutting).
Issue 664.
3. Added javadocs for FieldSelectorResult.java. (Grant Ingersoll)
4. Moved xdocs directory to src/site/src/documentation/content/xdocs per
Issue 707. Site now builds using Forrest, just like the other Lucene
siblings. See http://wiki.apache.org/jakarta-lucene/HowToUpdateTheWebsite
for info on updating the website. (Grant Ingersoll with help from Steve Rowe,
Chris Hostetter, Doug Cutting, Otis Gospodnetic, Yonik Seeley)
5. Added in Developer and System Requirements sections under Resources (Grant Ingersoll)
6. LUCENE-713 Updated the Term Vector section of File Formats to include
documentation on how Offset and Position info are stored in the TVF file.
(Grant Ingersoll, Samir Abdou)
7. Added in link to Clover Test Code Coverage Reports under the Develop
section in Resources (Grant Ingersoll)
8. LUCENE-748: Added details for semantics of IndexWriter.close on
hitting an Exception. (Jed Wesley-Smith via Mike McCandless)
9. Added some text about what is contained in releases.
(Eric Haszlakiewicz via Grant Ingersoll)
10. LUCENE-758: Fix javadoc to clarify that RAMDirectory(Directory)
makes a full copy of the starting Directory. (Mike McCandless)
11. LUCENE-764: Fix javadocs to detail temporary space requirements
for IndexWriter's optimize(), addIndexes(*) and addDocument(...)
methods. (Mike McCandless)
Build
1. Added in clover test code coverage per http://issues.apache.org/jira/browse/LUCENE-721
To enable clover code coverage, you must have clover.jar in the ANT
classpath and specify -Drun.clover=true on the command line.
(Michael Busch and Grant Ingersoll)
2. Added a sysproperty in common-build.xml per Lucene 752 to map java.io.tmpdir to
${build.dir}/test just like the tempDir sysproperty.
3. LUCENE-757 Added new target named init-dist that does setup for
distribution of both binary and source distributions. Called by package
and package-*-src
======================= Release 2.0.0 2006-05-26 =======================
API Changes
1. All deprecated methods and fields have been removed, except
DateField, which will still be supported for some time
so Lucene can read its date fields from old indexes
(Yonik Seeley & Grant Ingersoll)
2. DisjunctionSumScorer is no longer public.
(Paul Elschot via Otis Gospodnetic)
3. Creating a Field with both an empty name and an empty value
now throws an IllegalArgumentException
(Daniel Naber)
4. LUCENE-301: Added new IndexWriter({String,File,Directory},
Analyzer) constructors that do not take a boolean "create"
argument. These new constructors will create a new index if
necessary, else append to the existing one. (Dan Armbrust via
Mike McCandless)
New features
1. LUCENE-496: Command line tool for modifying the field norms of an
existing index; added to contrib/miscellaneous. (Chris Hostetter)
2. LUCENE-577: SweetSpotSimilarity added to contrib/miscellaneous.
(Chris Hostetter)
Bug fixes
1. LUCENE-330: Fix issue of FilteredQuery not working properly within
BooleanQuery. (Paul Elschot via Erik Hatcher)
2. LUCENE-515: Make ConstantScoreRangeQuery and ConstantScoreQuery work
with RemoteSearchable. (Philippe Laflamme via Yonik Seeley)
3. Added methods to get/set writeLockTimeout and commitLockTimeout in
IndexWriter. These could be set in Lucene 1.4 using a system property.
This feature had been removed without adding the corresponding
getter/setter methods. (Daniel Naber)
4. LUCENE-413: Fixed ArrayIndexOutOfBoundsException exceptions
when using SpanQueries. (Paul Elschot via Yonik Seeley)
5. Implemented FilterIndexReader.getVersion() and isCurrent()
(Yonik Seeley)
6. LUCENE-540: Fixed a bug with IndexWriter.addIndexes(Directory[])
that sometimes caused the index order of documents to change.
(Yonik Seeley)
7. LUCENE-526: Fixed a bug in FieldSortedHitQueue that caused
subsequent String sorts with different locales to sort identically.
(Paul Cowan via Yonik Seeley)
8. LUCENE-541: Add missing extractTerms() to DisjunctionMaxQuery
(Stefan Will via Yonik Seeley)
9. LUCENE-514: Added getTermArrays() and extractTerms() to
MultiPhraseQuery (Eric Jain & Yonik Seeley)
10. LUCENE-512: Fixed ClassCastException in ParallelReader.getTermFreqVectors
(frederic via Yonik)
11. LUCENE-352: Fixed bug in SpanNotQuery that manifested as
NullPointerException when "exclude" query was not a SpanTermQuery.
(Chris Hostetter)
12. LUCENE-572: Fixed bug in SpanNotQuery hashCode, was ignoring exclude clause
(Chris Hostetter)
13. LUCENE-561: Fixed some ParallelReader bugs. NullPointerException if the reader
didn't know about the field yet, reader didn't keep track if it had deletions,
and deleteDocument calls could circumvent synchronization on the subreaders.
(Chuck Williams via Yonik Seeley)
14. LUCENE-556: Added empty extractTerms() implementation to MatchAllDocsQuery and
ConstantScoreQuery in order to allow their use with a MultiSearcher.
(Yonik Seeley)
15. LUCENE-546: Removed 2GB file size limitations for RAMDirectory.
(Peter Royal, Michael Chan, Yonik Seeley)
16. LUCENE-485: Don't hold commit lock while removing obsolete index
files. (Luc Vanlerberghe via cutting)
1.9.1
Bug fixes
1. LUCENE-511: Fix a bug in the BufferedIndexOutput optimization
introduced in 1.9-final. (Shay Banon & Steven Tamm via cutting)
1.9 final
Note that this release is mostly but not 100% source compatible with
the previous release of Lucene (1.4.3). In other words, you should
make sure your application compiles with this version of Lucene before
you replace the old Lucene JAR with the new one. Many methods have
been deprecated in anticipation of release 2.0, so deprecation
warnings are to be expected when upgrading from 1.4.3 to 1.9.
Bug fixes
1. The fix that made IndexWriter.setMaxBufferedDocs(1) work had negative
effects on indexing performance and has thus been reverted. The
argument for setMaxBufferedDocs(int) must now at least be 2, otherwise
an exception is thrown. (Daniel Naber)
Optimizations
1. Optimized BufferedIndexOutput.writeBytes() to use
System.arraycopy() in more cases, rather than copying byte-by-byte.
(Lukas Zapletal via Cutting)
1.9 RC1
Requirements
1. To compile and use Lucene you now need Java 1.4 or later.
Changes in runtime behavior
1. FuzzyQuery can no longer throw a TooManyClauses exception. If a
FuzzyQuery expands to more than BooleanQuery.maxClauseCount
terms only the BooleanQuery.maxClauseCount most similar terms
go into the rewritten query and thus the exception is avoided.
(Christoph)
2. Changed system property from "org.apache.lucene.lockdir" to
"org.apache.lucene.lockDir", so that its casing follows the existing
pattern used in other Lucene system properties. (Bernhard)
3. The terms of RangeQueries and FuzzyQueries are now converted to
lowercase by default (as it has been the case for PrefixQueries
and WildcardQueries before). Use setLowercaseExpandedTerms(false)
to disable that behavior but note that this also affects
PrefixQueries and WildcardQueries. (Daniel Naber)
4. Document frequency that is computed when MultiSearcher is used is now
computed correctly and "globally" across subsearchers and indices, while
before it used to be computed locally to each index, which caused
ranking across multiple indices not to be equivalent.
(Chuck Williams, Wolf Siberski via Otis, bug #31841)
5. When opening an IndexWriter with create=true, Lucene now only deletes
its own files from the index directory (looking at the file name suffixes
to decide if a file belongs to Lucene). The old behavior was to delete
all files. (Daniel Naber and Bernhard Messer, bug #34695)
6. The version of an IndexReader, as returned by getCurrentVersion()
and getVersion() doesn't start at 0 anymore for new indexes. Instead, it
is now initialized by the system time in milliseconds.
(Bernhard Messer via Daniel Naber)
7. Several default values cannot be set via system properties anymore, as
this has been considered inappropriate for a library like Lucene. For
most properties there are set/get methods available in IndexWriter which
you should use instead. This affects the following properties:
See IndexWriter for getter/setter methods:
org.apache.lucene.writeLockTimeout, org.apache.lucene.commitLockTimeout,
org.apache.lucene.minMergeDocs, org.apache.lucene.maxMergeDocs,
org.apache.lucene.maxFieldLength, org.apache.lucene.termIndexInterval,
org.apache.lucene.mergeFactor,
See BooleanQuery for getter/setter methods:
org.apache.lucene.maxClauseCount
See FSDirectory for getter/setter methods:
disableLuceneLocks
(Daniel Naber)
8. Fixed FieldCacheImpl to use user-provided IntParser and FloatParser,
instead of using Integer and Float classes for parsing.
(Yonik Seeley via Otis Gospodnetic)
9. Expert level search routines returning TopDocs and TopFieldDocs
no longer normalize scores. This also fixes bugs related to
MultiSearchers and score sorting/normalization.
(Luc Vanlerberghe via Yonik Seeley, LUCENE-469)
New features
1. Added support for stored compressed fields (patch #31149)
(Bernhard Messer via Christoph)
2. Added support for binary stored fields (patch #29370)
(Drew Farris and Bernhard Messer via Christoph)
3. Added support for position and offset information in term vectors
(patch #18927). (Grant Ingersoll & Christoph)
4. A new class DateTools has been added. It allows you to format dates
in a readable format adequate for indexing. Unlike the existing
DateField class DateTools can cope with dates before 1970 and it
forces you to specify the desired date resolution (e.g. month, day,
second, ...) which can make RangeQuerys on those fields more efficient.
(Daniel Naber)
5. QueryParser now correctly works with Analyzers that can return more
than one token per position. For example, a query "+fast +car"
would be parsed as "+fast +(car automobile)" if the Analyzer
returns "car" and "automobile" at the same position whenever it
finds "car" (Patch #23307).
(Pierrick Brihaye, Daniel Naber)
6. Permit unbuffered Directory implementations (e.g., using mmap).
InputStream is replaced by the new classes IndexInput and
BufferedIndexInput. OutputStream is replaced by the new classes
IndexOutput and BufferedIndexOutput. InputStream and OutputStream
are now deprecated and FSDirectory is now subclassable. (cutting)
7. Add native Directory and TermDocs implementations that work under
GCJ. These require GCC 3.4.0 or later and have only been tested
on Linux. Use 'ant gcj' to build demo applications. (cutting)
8. Add MMapDirectory, which uses nio to mmap input files. This is
still somewhat slower than FSDirectory. However it uses less
memory per query term, since a new buffer is not allocated per
term, which may help applications which use, e.g., wildcard
queries. It may also someday be faster. (cutting & Paul Elschot)
9. Added javadocs-internal to build.xml - bug #30360
(Paul Elschot via Otis)
10. Added RangeFilter, a more generically useful filter than DateFilter.
(Chris M Hostetter via Erik)
11. Added NumberTools, a utility class indexing numeric fields.
(adapted from code contributed by Matt Quail; committed by Erik)
12. Added public static IndexReader.main(String[] args) method.
IndexReader can now be used directly at command line level
to list and optionally extract the individual files from an existing
compound index file.
(adapted from code contributed by Garrett Rooney; committed by Bernhard)
13. Add IndexWriter.setTermIndexInterval() method. See javadocs.
(Doug Cutting)
14. Added LucenePackage, whose static get() method returns java.util.Package,
which lets the caller get the Lucene version information specified in
the Lucene Jar.
(Doug Cutting via Otis)
15. Added Hits.iterator() method and corresponding HitIterator and Hit objects.
This provides standard java.util.Iterator iteration over Hits.
Each call to the iterator's next() method returns a Hit object.
(Jeremy Rayner via Erik)
16. Add ParallelReader, an IndexReader that combines separate indexes
over different fields into a single virtual index. (Doug Cutting)
17. Add IntParser and FloatParser interfaces to FieldCache, so that
fields in arbitrarily formats can be cached as ints and floats.
(Doug Cutting)
18. Added class org.apache.lucene.index.IndexModifier which combines
IndexWriter and IndexReader, so you can add and delete documents without
worrying about synchronization/locking issues.
(Daniel Naber)
19. Lucene can now be used inside an unsigned applet, as Lucene's access
to system properties will not cause a SecurityException anymore.
(Jon Schuster via Daniel Naber, bug #34359)
20. Added a new class MatchAllDocsQuery that matches all documents.
(John Wang via Daniel Naber, bug #34946)
21. Added ability to omit norms on a per field basis to decrease
index size and memory consumption when there are many indexed fields.
See Field.setOmitNorms()
(Yonik Seeley, LUCENE-448)
22. Added NullFragmenter to contrib/highlighter, which is useful for
highlighting entire documents or fields.
(Erik Hatcher)
23. Added regular expression queries, RegexQuery and SpanRegexQuery.
Note the same term enumeration caveats apply with these queries as
apply to WildcardQuery and other term expanding queries.
These two new queries are not currently supported via QueryParser.
(Erik Hatcher)
24. Added ConstantScoreQuery which wraps a filter and produces a score
equal to the query boost for every matching document.
(Yonik Seeley, LUCENE-383)
25. Added ConstantScoreRangeQuery which produces a constant score for
every document in the range. One advantage over a normal RangeQuery
is that it doesn't expand to a BooleanQuery and thus doesn't have a maximum
number of terms the range can cover. Both endpoints may also be open.
(Yonik Seeley, LUCENE-383)
26. Added ability to specify a minimum number of optional clauses that
must match in a BooleanQuery. See BooleanQuery.setMinimumNumberShouldMatch().
(Paul Elschot, Chris Hostetter via Yonik Seeley, LUCENE-395)
27. Added DisjunctionMaxQuery which provides the maximum score across its clauses.
It's very useful for searching across multiple fields.
(Chuck Williams via Yonik Seeley, LUCENE-323)
28. New class ISOLatin1AccentFilter that replaces accented characters in the ISO
Latin 1 character set by their unaccented equivalent.
(Sven Duzont via Erik Hatcher)
29. New class KeywordAnalyzer. "Tokenizes" the entire stream as a single token.
This is useful for data like zip codes, ids, and some product names.
(Erik Hatcher)
30. Copied LengthFilter from contrib area to core. Removes words that are too
long and too short from the stream.
(David Spencer via Otis and Daniel)
31. Added getPositionIncrementGap(String fieldName) to Analyzer. This allows
custom analyzers to put gaps between Field instances with the same field
name, preventing phrase or span queries crossing these boundaries. The
default implementation issues a gap of 0, allowing the default token
position increment of 1 to put the next field's first token into a
successive position.
(Erik Hatcher, with advice from Yonik)
32. StopFilter can now ignore case when checking for stop words.
(Grant Ingersoll via Yonik, LUCENE-248)
33. Add TopDocCollector and TopFieldDocCollector. These simplify the
implementation of hit collectors that collect only the
top-scoring or top-sorting hits.
API Changes
1. Several methods and fields have been deprecated. The API documentation
contains information about the recommended replacements. It is planned
that most of the deprecated methods and fields will be removed in
Lucene 2.0. (Daniel Naber)
2. The Russian and the German analyzers have been moved to contrib/analyzers.
Also, the WordlistLoader class has been moved one level up in the
hierarchy and is now org.apache.lucene.analysis.WordlistLoader
(Daniel Naber)
3. The API contained methods that declared to throw an IOException
but that never did this. These declarations have been removed. If
your code tries to catch these exceptions you might need to remove
those catch clauses to avoid compile errors. (Daniel Naber)
4. Add a serializable Parameter Class to standardize parameter enum
classes in BooleanClause and Field. (Christoph)
5. Added rewrite methods to all SpanQuery subclasses that nest other SpanQuerys.
This allows custom SpanQuery subclasses that rewrite (for term expansion, for
example) to nest within the built-in SpanQuery classes successfully.
Bug fixes
1. The JSP demo page (src/jsp/results.jsp) now properly closes the
IndexSearcher it opens. (Daniel Naber)
2. Fixed a bug in IndexWriter.addIndexes(IndexReader[] readers) that
prevented deletion of obsolete segments. (Christoph Goller)
3. Fix in FieldInfos to avoid the return of an extra blank field in
IndexReader.getFieldNames() (Patch #19058). (Mark Harwood via Bernhard)
4. Some combinations of BooleanQuery and MultiPhraseQuery (formerly
PhrasePrefixQuery) could provoke UnsupportedOperationException
(bug #33161). (Rhett Sutphin via Daniel Naber)
5. Small bug in skipTo of ConjunctionScorer that caused NullPointerException
if skipTo() was called without prior call to next() fixed. (Christoph)
6. Disable Similiarty.coord() in the scoring of most automatically
generated boolean queries. The coord() score factor is
appropriate when clauses are independently specified by a user,
but is usually not appropriate when clauses are generated
automatically, e.g., by a fuzzy, wildcard or range query. Matches
on such automatically generated queries are no longer penalized
for not matching all terms. (Doug Cutting, Patch #33472)
7. Getting a lock file with Lock.obtain(long) was supposed to wait for
a given amount of milliseconds, but this didn't work.
(John Wang via Daniel Naber, Bug #33799)
8. Fix FSDirectory.createOutput() to always create new files.
Previously, existing files were overwritten, and an index could be
corrupted when the old version of a file was longer than the new.
Now any existing file is first removed. (Doug Cutting)
9. Fix BooleanQuery containing nested SpanTermQuery's, which previously
could return an incorrect number of hits.
(Reece Wilton via Erik Hatcher, Bug #35157)
10. Fix NullPointerException that could occur with a MultiPhraseQuery
inside a BooleanQuery.
(Hans Hjelm and Scotty Allen via Daniel Naber, Bug #35626)
11. Fixed SnowballFilter to pass through the position increment from
the original token.
(Yonik Seeley via Erik Hatcher, LUCENE-437)
12. Added Unicode range of Korean characters to StandardTokenizer,
grouping contiguous characters into a token rather than one token
per character. This change also changes the token type to "<CJ>"
for Chinese and Japanese character tokens (previously it was "<CJK>").
(Cheolgoo Kang via Otis and Erik, LUCENE-444 and LUCENE-461)
13. FieldsReader now looks at FieldInfo.storeOffsetWithTermVector and
FieldInfo.storePositionWithTermVector and creates the Field with
correct TermVector parameter.
(Frank Steinmann via Bernhard, LUCENE-455)
14. Fixed WildcardQuery to prevent "cat" matching "ca??".
(Xiaozheng Ma via Bernhard, LUCENE-306)
15. Fixed a bug where MultiSearcher and ParallelMultiSearcher could
change the sort order when sorting by string for documents without
a value for the sort field.
(Luc Vanlerberghe via Yonik, LUCENE-453)
16. Fixed a sorting problem with MultiSearchers that can lead to
missing or duplicate docs due to equal docs sorting in an arbitrary order.
(Yonik Seeley, LUCENE-456)
17. A single hit using the expert level sorted search methods
resulted in the score not being normalized.
(Yonik Seeley, LUCENE-462)
18. Fixed inefficient memory usage when loading an index into RAMDirectory.
(Volodymyr Bychkoviak via Bernhard, LUCENE-475)
19. Corrected term offsets returned by ChineseTokenizer.
(Ray Tsang via Erik Hatcher, LUCENE-324)
20. Fixed MultiReader.undeleteAll() to correctly update numDocs.
(Robert Kirchgessner via Doug Cutting, LUCENE-479)
21. Race condition in IndexReader.getCurrentVersion() and isCurrent()
fixed by acquiring the commit lock.
(Luc Vanlerberghe via Yonik Seeley, LUCENE-481)
22. IndexWriter.setMaxBufferedDocs(1) didn't have the expected effect,
this has now been fixed. (Daniel Naber)
23. Fixed QueryParser when called with a date in local form like
"[1/16/2000 TO 1/18/2000]". This query did not include the documents
of 1/18/2000, i.e. the last day was not included. (Daniel Naber)
24. Removed sorting constraint that threw an exception if there were
not yet any values for the sort field (Yonik Seeley, LUCENE-374)
Optimizations
1. Disk usage (peak requirements during indexing and optimization)
in case of compound file format has been improved.
(Bernhard, Dmitry, and Christoph)
2. Optimize the performance of certain uses of BooleanScorer,
TermScorer and IndexSearcher. In particular, a BooleanQuery
composed of TermQuery, with not all terms required, that returns a
TopDocs (e.g., through a Hits with no Sort specified) runs much
faster. (cutting)
3. Removed synchronization from reading of term vectors with an
IndexReader (Patch #30736). (Bernhard Messer via Christoph)
4. Optimize term-dictionary lookup to allocate far fewer terms when
scanning for the matching term. This speeds searches involving
low-frequency terms, where the cost of dictionary lookup can be
significant. (cutting)
5. Optimize fuzzy queries so the standard fuzzy queries with a prefix
of 0 now run 20-50% faster (Patch #31882).
(Jonathan Hager via Daniel Naber)
6. A Version of BooleanScorer (BooleanScorer2) added that delivers
documents in increasing order and implements skipTo. For queries
with required or forbidden clauses it may be faster than the old
BooleanScorer, for BooleanQueries consisting only of optional
clauses it is probably slower. The new BooleanScorer is now the
default. (Patch 31785 by Paul Elschot via Christoph)
7. Use uncached access to norms when merging to reduce RAM usage.
(Bug #32847). (Doug Cutting)
8. Don't read term index when random-access is not required. This
reduces time to open IndexReaders and they use less memory when
random access is not required, e.g., when merging segments. The
term index is now read into memory lazily at the first
random-access. (Doug Cutting)
9. Optimize IndexWriter.addIndexes(Directory[]) when the number of
added indexes is larger than mergeFactor. Previously this could
result in quadratic performance. Now performance is n log(n).
(Doug Cutting)
10. Speed up the creation of TermEnum for indices with multiple
segments and deleted documents, and thus speed up PrefixQuery,
RangeQuery, WildcardQuery, FuzzyQuery, RangeFilter, DateFilter,
and sorting the first time on a field.
(Yonik Seeley, LUCENE-454)
11. Optimized and generalized 32 bit floating point to byte
(custom 8 bit floating point) conversions. Increased the speed of
Similarity.encodeNorm() anywhere from 10% to 250%, depending on the JVM.
(Yonik Seeley, LUCENE-467)
Infrastructure
1. Lucene's source code repository has converted from CVS to
Subversion. The new repository is at
http://svn.apache.org/repos/asf/lucene/java/trunk
2. Lucene's issue tracker has migrated from Bugzilla to JIRA.
Lucene's JIRA is at http://issues.apache.org/jira/browse/LUCENE
The old issues are still available at
http://issues.apache.org/bugzilla/show_bug.cgi?id=xxxx
(use the bug number instead of xxxx)
1.4.3
1. The JSP demo page (src/jsp/results.jsp) now properly escapes error
messages which might contain user input (e.g. error messages about
query parsing). If you used that page as a starting point for your
own code please make sure your code also properly escapes HTML
characters from user input in order to avoid so-called cross site
scripting attacks. (Daniel Naber)
2. QueryParser changes in 1.4.2 broke the QueryParser API. Now the old
API is supported again. (Christoph)
1.4.2
1. Fixed bug #31241: Sorting could lead to incorrect results (documents
missing, others duplicated) if the sort keys were not unique and there
were more than 100 matches. (Daniel Naber)
2. Memory leak in Sort code (bug #31240) eliminated.
(Rafal Krzewski via Christoph and Daniel)
3. FuzzyQuery now takes an additional parameter that specifies the
minimum similarity that is required for a term to match the query.
The QueryParser syntax for this is term~x, where x is a floating
point number >= 0 and < 1 (a bigger number means that a higher
similarity is required). Furthermore, a prefix can be specified
for FuzzyQuerys so that only those terms are considered similar that
start with this prefix. This can speed up FuzzyQuery greatly.
(Daniel Naber, Christoph Goller)
4. PhraseQuery and PhrasePrefixQuery now allow the explicit specification
of relative positions. (Christoph Goller)
5. QueryParser changes: Fix for ArrayIndexOutOfBoundsExceptions
(patch #9110); some unused method parameters removed; The ability
to specify a minimum similarity for FuzzyQuery has been added.
(Christoph Goller)
6. IndexSearcher optimization: a new ScoreDoc is no longer allocated
for every non-zero-scoring hit. This makes 'OR' queries that
contain common terms substantially faster. (cutting)
1.4.1
1. Fixed a performance bug in hit sorting code, where values were not
correctly cached. (Aviran via cutting)
2. Fixed errors in file format documentation. (Daniel Naber)
1.4 final
1. Added "an" to the list of stop words in StopAnalyzer, to complement
the existing "a" there. Fix for bug 28960
(http://issues.apache.org/bugzilla/show_bug.cgi?id=28960). (Otis)
2. Added new class FieldCache to manage in-memory caches of field term
values. (Tim Jones)
3. Added overloaded getFieldQuery method to QueryParser which
accepts the slop factor specified for the phrase (or the default
phrase slop for the QueryParser instance). This allows overriding
methods to replace a PhraseQuery with a SpanNearQuery instead,
keeping the proper slop factor. (Erik Hatcher)
4. Changed the encoding of GermanAnalyzer.java and GermanStemmer.java to
UTF-8 and changed the build encoding to UTF-8, to make changed files
compile. (Otis Gospodnetic)
5. Removed synchronization from term lookup under IndexReader methods
termFreq(), termDocs() or termPositions() to improve
multi-threaded performance. (cutting)
6. Fix a bug where obsolete segment files were not deleted on Win32.
1.4 RC3
1. Fixed several search bugs introduced by the skipTo() changes in
release 1.4RC1. The index file format was changed a bit, so
collections must be re-indexed to take advantage of the skipTo()
optimizations. (Christoph Goller)
2. Added new Document methods, removeField() and removeFields().
(Christoph Goller)
3. Fixed inconsistencies with index closing. Indexes and directories
are now only closed automatically by Lucene when Lucene opened
them automatically. (Christoph Goller)
4. Added new class: FilteredQuery. (Tim Jones)
5. Added a new SortField type for custom comparators. (Tim Jones)
6. Lock obtain timed out message now displays the full path to the lock
file. (Daniel Naber via Erik)
7. Fixed a bug in SpanNearQuery when ordered. (Paul Elschot via cutting)
8. Fixed so that FSDirectory's locks still work when the
java.io.tmpdir system property is null. (cutting)
9. Changed FilteredTermEnum's constructor to take no parameters,
as the parameters were ignored anyway (bug #28858)
1.4 RC2
1. GermanAnalyzer now throws an exception if the stopword file
cannot be found (bug #27987). It now uses LowerCaseFilter
(bug #18410) (Daniel Naber via Otis, Erik)
2. Fixed a few bugs in the file format documentation. (cutting)
1.4 RC1
1. Changed the format of the .tis file, so that:
- it has a format version number, which makes it easier to
back-compatibly change file formats in the future.
- the term count is now stored as a long. This was the one aspect
of the Lucene's file formats which limited index size.
- a few internal index parameters are now stored in the index, so
that they can (in theory) now be changed from index to index,
although there is not yet an API to do so.
These changes are back compatible. The new code can read old
indexes. But old code will not be able read new indexes. (cutting)
2. Added an optimized implementation of TermDocs.skipTo(). A skip
table is now stored for each term in the .frq file. This only
adds a percent or two to overall index size, but can substantially
speedup many searches. (cutting)
3. Restructured the Scorer API and all Scorer implementations to take
advantage of an optimized TermDocs.skipTo() implementation. In
particular, PhraseQuerys and conjunctive BooleanQuerys are
faster when one clause has substantially fewer matches than the
others. (A conjunctive BooleanQuery is a BooleanQuery where all
clauses are required.) (cutting)
4. Added new class ParallelMultiSearcher. Combined with
RemoteSearchable this makes it easy to implement distributed
search systems. (Jean-Francois Halleux via cutting)
5. Added support for hit sorting. Results may now be sorted by any
indexed field. For details see the javadoc for
Searcher#search(Query, Sort). (Tim Jones via Cutting)
6. Changed FSDirectory to auto-create a full directory tree that it
needs by using mkdirs() instead of mkdir(). (Mladen Turk via Otis)
7. Added a new span-based query API. This implements, among other
things, nested phrases. See javadocs for details. (Doug Cutting)
8. Added new method Query.getSimilarity(Searcher), and changed
scorers to use it. This permits one to subclass a Query class so
that it can specify its own Similarity implementation, perhaps
one that delegates through that of the Searcher. (Julien Nioche
via Cutting)
9. Added MultiReader, an IndexReader that combines multiple other
IndexReaders. (Cutting)
10. Added support for term vectors. See Field#isTermVectorStored().
(Grant Ingersoll, Cutting & Dmitry)
11. Fixed the old bug with escaping of special characters in query
strings: http://issues.apache.org/bugzilla/show_bug.cgi?id=24665
(Jean-Francois Halleux via Otis)
12. Added support for overriding default values for the following,
using system properties:
- default commit lock timeout
- default maxFieldLength
- default maxMergeDocs
- default mergeFactor
- default minMergeDocs
- default write lock timeout
(Otis)
13. Changed QueryParser.jj to allow '-' and '+' within tokens:
http://issues.apache.org/bugzilla/show_bug.cgi?id=27491
(Morus Walter via Otis)
14. Changed so that the compound index format is used by default.
This makes indexing a bit slower, but vastly reduces the chances
of file handle problems. (Cutting)
1.3 final
1. Added catch of BooleanQuery$TooManyClauses in QueryParser to
throw ParseException instead. (Erik Hatcher)
2. Fixed a NullPointerException in Query.explain(). (Doug Cutting)
3. Added a new method IndexReader.setNorm(), that permits one to
alter the boosting of fields after an index is created.
4. Distinguish between the final position and length when indexing a
field. The length is now defined as the total number of tokens,
instead of the final position, as it was previously. Length is
used for score normalization (Similarity.lengthNorm()) and for
controlling memory usage (IndexWriter.maxFieldLength). In both of
these cases, the total number of tokens is a better value to use
than the final token position. Position is used in phrase
searching (see PhraseQuery and Token.setPositionIncrement()).
5. Fix StandardTokenizer's handling of CJK characters (Chinese,
Japanese and Korean ideograms). Previously contiguous sequences
were combined in a single token, which is not very useful. Now
each ideogram generates a separate token, which is more useful.
1.3 RC3
1. Added minMergeDocs in IndexWriter. This can be raised to speed
indexing without altering the number of files, but only using more
memory. (Julien Nioche via Otis)
2. Fix bug #24786, in query rewriting. (bschneeman via Cutting)
3. Fix bug #16952, in demo HTML parser, skip comments in
javascript. (Christoph Goller)
4. Fix bug #19253, in demo HTML parser, add whitespace as needed to
output (Daniel Naber via Christoph Goller)
5. Fix bug #24301, in demo HTML parser, long titles no longer
hang things. (Christoph Goller)
6. Fix bug #23534, Replace use of file timestamp of segments file
with an index version number stored in the segments file. This
resolves problems when running on file systems with low-resolution
timestamps, e.g., HFS under MacOS X. (Christoph Goller)
7. Fix QueryParser so that TokenMgrError is not thrown, only
ParseException. (Erik Hatcher)
8. Fix some bugs introduced by change 11 of RC2. (Christoph Goller)
9. Fixed a problem compiling TestRussianStem. (Christoph Goller)
10. Cleaned up some build stuff. (Erik Hatcher)
1.3 RC2
1. Added getFieldNames(boolean) to IndexReader, SegmentReader, and
SegmentsReader. (Julien Nioche via otis)
2. Changed file locking to place lock files in
System.getProperty("java.io.tmpdir"), where all users are
permitted to write files. This way folks can open and correctly
lock indexes which are read-only to them.
3. IndexWriter: added a new method, addDocument(Document, Analyzer),
permitting one to easily use different analyzers for different
documents in the same index.
4. Minor enhancements to FuzzyTermEnum.
(Christoph Goller via Otis)
5. PriorityQueue: added insert(Object) method and adjusted IndexSearcher
and MultiIndexSearcher to use it.
(Christoph Goller via Otis)
6. Fixed a bug in IndexWriter that returned incorrect docCount().
(Christoph Goller via Otis)
7. Fixed SegmentsReader to eliminate the confusing and slightly different
behaviour of TermEnum when dealing with an enumeration of all terms,
versus an enumeration starting from a specific term.
This patch also fixes incorrect term document frequencies when the same term
is present in multiple segments.
(Christoph Goller via Otis)
8. Added CachingWrapperFilter and PerFieldAnalyzerWrapper. (Erik Hatcher)
9. Added support for the new "compound file" index format (Dmitry
Serebrennikov)
10. Added Locale setting to QueryParser, for use by date range parsing.
11. Changed IndexReader so that it can be subclassed by classes
outside of its package. Previously it had package-private
abstract methods. Also modified the index merging code so that it
can work on an arbitrary IndexReader implementation, and added a
new method, IndexWriter.addIndexes(IndexReader[]), to take
advantage of this. (cutting)
12. Added a limit to the number of clauses which may be added to a
BooleanQuery. The default limit is 1024 clauses. This should
stop most OutOfMemoryExceptions by prefix, wildcard and fuzzy
queries which run amok. (cutting)
13. Add new method: IndexReader.undeleteAll(). This undeletes all
deleted documents which still remain in the index. (cutting)
1.3 RC1
1. Fixed PriorityQueue's clear() method.
Fix for bug 9454, http://nagoya.apache.org/bugzilla/show_bug.cgi?id=9454
(Matthijs Bomhoff via otis)
2. Changed StandardTokenizer.jj grammar for EMAIL tokens.
Fix for bug 9015, http://nagoya.apache.org/bugzilla/show_bug.cgi?id=9015
(Dale Anson via otis)
3. Added the ability to disable lock creation by using disableLuceneLocks
system property. This is useful for read-only media, such as CD-ROMs.
(otis)
4. Added id method to Hits to be able to access the index global id.
Required for sorting options.
(carlson)
5. Added support for new range query syntax to QueryParser.jj.
(briangoetz)
6. Added the ability to retrieve HTML documents' META tag values to
HTMLParser.jj.
(Mark Harwood via otis)
7. Modified QueryParser to make it possible to programmatically specify the
default Boolean operator (OR or AND).
(Péter Halácsy via otis)
8. Made many search methods and classes non-final, per requests.
This includes IndexWriter and IndexSearcher, among others.
(cutting)
9. Added class RemoteSearchable, providing support for remote
searching via RMI. The test class RemoteSearchableTest.java
provides an example of how this can be used. (cutting)
10. Added PhrasePrefixQuery (and supporting MultipleTermPositions). The
test class TestPhrasePrefixQuery provides the usage example.
(Anders Nielsen via otis)
11. Changed the German stemming algorithm to ignore case while
stripping. The new algorithm is faster and produces more equal
stems from nouns and verbs derived from the same word.
(gschwarz)
12. Added support for boosting the score of documents and fields via
the new methods Document.setBoost(float) and Field.setBoost(float).
Note: This changes the encoding of an indexed value. Indexes
should be re-created from scratch in order for search scores to
be correct. With the new code and an old index, searches will
yield very large scores for shorter fields, and very small scores
for longer fields. Once the index is re-created, scores will be
as before. (cutting)
13. Added new method Token.setPositionIncrement().
This permits, for the purpose of phrase searching, placing
multiple terms in a single position. This is useful with
stemmers that produce multiple possible stems for a word.
This also permits the introduction of gaps between terms, so that
terms which are adjacent in a token stream will not be matched by
and exact phrase query. This makes it possible, e.g., to build
an analyzer where phrases are not matched over stop words which
have been removed.
Finally, repeating a token with an increment of zero can also be
used to boost scores of matches on that token. (cutting)
14. Added new Filter class, QueryFilter. This constrains search
results to only match those which also match a provided query.
Results are cached, so that searches after the first on the same
index using this filter are very fast.
This could be used, for example, with a RangeQuery on a formatted
date field to implement date filtering. One could re-use a
single QueryFilter that matches, e.g., only documents modified
within the last week. The QueryFilter and RangeQuery would only
need to be reconstructed once per day. (cutting)
15. Added a new IndexWriter method, getAnalyzer(). This returns the
analyzer used when adding documents to this index. (cutting)
16. Fixed a bug with IndexReader.lastModified(). Before, document
deletion did not update this. Now it does. (cutting)
17. Added Russian Analyzer.
(Boris Okner via otis)
18. Added a public, extensible scoring API. For details, see the
javadoc for org.apache.lucene.search.Similarity.
19. Fixed return of Hits.id() from float to int. (Terry Steichen via Peter).
20. Added getFieldNames() to IndexReader and Segment(s)Reader classes.
(Peter Mularien via otis)
21. Added getFields(String) and getValues(String) methods.
Contributed by Rasik Pandey on 2002-10-09
(Rasik Pandey via otis)
22. Revised internal search APIs. Changes include:
a. Queries are no longer modified during a search. This makes
it possible, e.g., to reuse the same query instance with
multiple indexes from multiple threads.
b. Term-expanding queries (e.g. PrefixQuery, WildcardQuery,
etc.) now work correctly with MultiSearcher, fixing bugs 12619
and 12667.
c. Boosting BooleanQuery's now works, and is supported by the
query parser (problem reported by Lee Mallabone). Thus a query
like "(+foo +bar)^2 +baz" is now supported and equivalent to
"(+foo^2 +bar^2) +baz".
d. New method: Query.rewrite(IndexReader). This permits a
query to re-write itself as an alternate, more primitive query.
Most of the term-expanding query classes (PrefixQuery,
WildcardQuery, etc.) are now implemented using this method.
e. New method: Searchable.explain(Query q, int doc). This
returns an Explanation instance that describes how a particular
document is scored against a query. An explanation can be
displayed as either plain text, with the toString() method, or
as HTML, with the toHtml() method. Note that computing an
explanation is as expensive as executing the query over the
entire index. This is intended to be used in developing
Similarity implementations, and, for good performance, should
not be displayed with every hit.
f. Scorer and Weight are public, not package protected. It now
possible for someone to write a Scorer implementation that is
not in the org.apache.lucene.search package. This is still
fairly advanced programming, and I don't expect anyone to do
this anytime soon, but at least now it is possible.
g. Added public accessors to the primitive query classes
(TermQuery, PhraseQuery and BooleanQuery), permitting access to
their terms and clauses.
Caution: These are extensive changes and they have not yet been
tested extensively. Bug reports are appreciated.
(cutting)
23. Added convenience RAMDirectory constructors taking File and String
arguments, for easy FSDirectory to RAMDirectory conversion.
(otis)
24. Added code for manual renaming of files in FSDirectory, since it
has been reported that java.io.File's renameTo(File) method sometimes
fails on Windows JVMs.
(Matt Tucker via otis)
25. Refactored QueryParser to make it easier for people to extend it.
Added the ability to automatically lower-case Wildcard terms in
the QueryParser.
(Tatu Saloranta via otis)
1.2 RC6
1. Changed QueryParser.jj to have "?" be a special character which
allowed it to be used as a wildcard term. Updated TestWildcard
unit test also. (Ralf Hettesheimer via carlson)
1.2 RC5
1. Renamed build.properties to default.properties and updated
the BUILD.txt document to describe how to override the
default.property settings without having to edit the file. This
brings the build process closer to Scarab's build process.
(jon)
2. Added MultiFieldQueryParser class. (Kelvin Tan, via otis)
3. Updated "powered by" links. (otis)
4. Fixed instruction for setting up JavaCC - Bug #7017 (otis)
5. Added throwing exception if FSDirectory could not create directory
- Bug #6914 (Eugene Gluzberg via otis)
6. Update MultiSearcher, MultiFieldParse, Constants, DateFilter,
LowerCaseTokenizer javadoc (otis)
7. Added fix to avoid NullPointerException in results.jsp
(Mark Hayes via otis)
8. Changed Wildcard search to find 0 or more char instead of 1 or more
(Lee Mallobone, via otis)
9. Fixed error in offset issue in GermanStemFilter - Bug #7412
(Rodrigo Reyes, via otis)
10. Added unit tests for wildcard search and DateFilter (otis)
11. Allow co-existence of indexed and non-indexed fields with the same name
(cutting/casper, via otis)
12. Add escape character to query parser.
(briangoetz)
13. Applied a patch that ensures that searches that use DateFilter
don't throw an exception when no matches are found. (David Smiley, via
otis)
14. Fixed bugs in DateFilter and wildcardquery unit tests. (cutting, otis, carlson)
1.2 RC4
1. Updated contributions section of website.
Add XML Document #3 implementation to Document Section.
Also added Term Highlighting to Misc Section. (carlson)
2. Fixed NullPointerException for phrase searches containing
unindexed terms, introduced in 1.2RC3. (cutting)
3. Changed document deletion code to obtain the index write lock,
enforcing the fact that document addition and deletion cannot be
performed concurrently. (cutting)
4. Various documentation cleanups. (otis, acoliver)
5. Updated "powered by" links. (cutting, jon)
6. Fixed a bug in the GermanStemmer. (Bernhard Messer, via otis)
7. Changed Term and Query to implement Serializable. (scottganyo)
8. Fixed to never delete indexes added with IndexWriter.addIndexes().
(cutting)
9. Upgraded to JUnit 3.7. (otis)
1.2 RC3
1. IndexWriter: fixed a bug where adding an optimized index to an
empty index failed. This was encountered using addIndexes to copy
a RAMDirectory index to an FSDirectory.
2. RAMDirectory: fixed a bug where RAMInputStream could not read
across more than across a single buffer boundary.
3. Fix query parser so it accepts queries with unicode characters.
(briangoetz)
4. Fix query parser so that PrefixQuery is used in preference to
WildcardQuery when there's only an asterisk at the end of the
term. Previously PrefixQuery would never be used.
5. Fix tests so they compile; fix ant file so it compiles tests
properly. Added test cases for Analyzers and PriorityQueue.
6. Updated demos, added Getting Started documentation. (acoliver)
7. Added 'contributions' section to website & docs. (carlson)
8. Removed JavaCC from source distribution for copyright reasons.
Folks must now download this separately from metamata in order to
compile Lucene. (cutting)
9. Substantially improved the performance of DateFilter by adding the
ability to reuse TermDocs objects. (cutting)
10. Added IndexReader methods:
public static boolean indexExists(String directory);
public static boolean indexExists(File directory);
public static boolean indexExists(Directory directory);
public static boolean isLocked(Directory directory);
public static void unlock(Directory directory);
(cutting, otis)
11. Fixed bugs in GermanAnalyzer (gschwarz)
1.2 RC2, 19 October 2001:
- added sources to distribution
- removed broken build scripts and libraries from distribution
- SegmentsReader: fixed potential race condition
- FSDirectory: fixed so that getDirectory(xxx,true) correctly
erases the directory contents, even when the directory
has already been accessed in this JVM.
- RangeQuery: Fix issue where an inclusive range query would
include the nearest term in the index above a non-existant
specified upper term.
- SegmentTermEnum: Fix NullPointerException in clone() method
when the Term is null.
- JDK 1.1 compatibility fix: disabled lock files for JDK 1.1,
since they rely on a feature added in JDK 1.2.
1.2 RC1 (first Apache release), 2 October 2001:
- packages renamed from com.lucene to org.apache.lucene
- license switched from LGPL to Apache
- ant-only build -- no more makefiles
- addition of lock files--now fully thread & process safe
- addition of German stemmer
- MultiSearcher now supports low-level search API
- added RangeQuery, for term-range searching
- Analyzers can choose tokenizer based on field name
- misc bug fixes.
1.01b (last Sourceforge release), 2 July 2001
. a few bug fixes
. new Query Parser
. new prefix query (search for "foo*" matches "food")
1.0, 2000-10-04
This release fixes a few serious bugs and also includes some
performance optimizations, a stemmer, and a few other minor
enhancements.
0.04 2000-04-19
Lucene now includes a grammar-based tokenizer, StandardTokenizer.
The only tokenizer included in the previous release (LetterTokenizer)
identified terms consisting entirely of alphabetic characters. The
new tokenizer uses a regular-expression grammar to identify more
complex classes of terms, including numbers, acronyms, email
addresses, etc.
StandardTokenizer serves two purposes:
1. It is a much better, general purpose tokenizer for use by
applications as is.
The easiest way for applications to start using
StandardTokenizer is to use StandardAnalyzer.
2. It provides a good example of grammar-based tokenization.
If an application has special tokenization requirements, it can
implement a custom tokenizer by copying the directory containing
the new tokenizer into the application and modifying it
accordingly.
0.01, 2000-03-30
First open source release.
The code has been re-organized into a new package and directory
structure for this release. It builds OK, but has not been tested
beyond that since the re-organization.