[
https://issues.apache.org/jira/browse/LUCENE-7526?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15616549#comment-15616549
]
ASF GitHub Bot commented on LUCENE-7526:
----------------------------------------
Github user dsmiley commented on a diff in the pull request:
https://github.com/apache/lucene-solr/pull/105#discussion_r85607262
--- Diff:
lucene/highlighter/src/java/org/apache/lucene/search/uhighlight/TokenStreamOffsetStrategy.java
---
@@ -0,0 +1,60 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.lucene.search.uhighlight;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.util.Collections;
+import java.util.List;
+
+import org.apache.lucene.analysis.Analyzer;
+import org.apache.lucene.analysis.TokenStream;
+import org.apache.lucene.index.IndexReader;
+import org.apache.lucene.index.PostingsEnum;
+import org.apache.lucene.util.BytesRef;
+import org.apache.lucene.util.automaton.CharacterRunAutomaton;
+
+public class TokenStreamOffsetStrategy extends AnalysisOffsetStrategy {
+
+ private static final BytesRef[] ZERO_LEN_BYTES_REF_ARRAY = new
BytesRef[0];
+
+ public TokenStreamOffsetStrategy(String field, BytesRef[] terms,
PhraseHelper phraseHelper, CharacterRunAutomaton[] automata, Analyzer
indexAnalyzer) {
+ super(field, terms, phraseHelper, automata, indexAnalyzer);
+ this.automata = convertTermsToAutomata(terms, automata);
+ this.terms = ZERO_LEN_BYTES_REF_ARRAY;
+ }
+
+ @Override
+ public List<OffsetsEnum> getOffsetsEnums(IndexReader reader, int docId,
String content) throws IOException {
+ TokenStream tokenStream = tokenStream(content);
+ PostingsEnum mtqPostingsEnum =
MultiTermHighlighting.getDocsEnum(tokenStream, automata);
--- End diff --
I think there's a case to be made in moving `
MultiTermHighlighting.getDocsEnum` into this class, to thus keep the
TokenStream aspect more isolated?
> Improvements to UnifiedHighlighter OffsetStrategies
> ---------------------------------------------------
>
> Key: LUCENE-7526
> URL: https://issues.apache.org/jira/browse/LUCENE-7526
> Project: Lucene - Core
> Issue Type: Improvement
> Components: modules/highlighter
> Reporter: Timothy M. Rodriguez
> Assignee: David Smiley
> Priority: Minor
> Fix For: 6.4
>
>
> This ticket improves several of the UnifiedHighlighter FieldOffsetStrategies
> by reducing reliance on creating or re-creating TokenStreams.
> The primary changes are as follows:
> * AnalysisOffsetStrategy - split into two offset strategies
> ** MemoryIndexOffsetStrategy - the primary analysis mode that utilizes a
> MemoryIndex for producing Offsets
> ** TokenStreamOffsetStrategy - an offset strategy that avoids creating a
> MemoryIndex. Can only be used if the query distills down to terms and
> automata.
> * TokenStream removal
> ** MemoryIndexOffsetStrategy - previously a TokenStream was created to fill
> the memory index and then once consumed a new one was generated by
> uninverting the MemoryIndex back into a TokenStream if there were automata
> (wildcard/mtq queries) involved. Now this is avoided, which should save
> memory and avoid a second pass over the data.
> ** TermVectorOffsetStrategy - this was refactored in a similar way to avoid
> generating a TokenStream if automata are involved.
> ** PostingsWithTermVectorsOffsetStrategy - similar refactoring
> * CompositePostingsEnum - aggregates several underlying PostingsEnums for
> wildcard/mtq queries. This should improve relevancy by providing unified
> metrics for a wildcard across all it's term matches
> * Added a HighlightFlag for enabling the newly separated
> TokenStreamOffsetStrategy since it can adversely affect passage relevancy
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
