org.apache.solr.spelling.suggest.fst.FuzzyLookupFactory Maven / Gradle / Ivy
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* 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.solr.spelling.suggest.fst;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.search.suggest.Lookup;
import org.apache.lucene.search.suggest.analyzing.FuzzySuggester;
import org.apache.lucene.util.automaton.LevenshteinAutomata;
import org.apache.solr.common.util.NamedList;
import org.apache.solr.core.SolrCore;
import org.apache.solr.schema.FieldType;
import org.apache.solr.spelling.suggest.LookupFactory;
/**
* Factory for {@link FuzzySuggester}
* @lucene.experimental
*/
public class FuzzyLookupFactory extends LookupFactory {
/**
* If true
, maxEdits, minFuzzyLength, transpositions and nonFuzzyPrefix
* will be measured in Unicode code points (actual letters) instead of bytes.
*/
public static final String UNICODE_AWARE = "unicodeAware";
/**
* Maximum number of edits allowed, used by {@link LevenshteinAutomata#toAutomaton(int)}
* in bytes or Unicode code points (if {@link #UNICODE_AWARE} option is set to true).
*/
public static final String MAX_EDITS = "maxEdits";
/**
* If transpositions are allowed, Fuzzy suggestions will be computed based on a primitive
* edit operation. If it is false, it will be based on the classic Levenshtein algorithm.
* Transpositions of bytes or Unicode code points (if {@link #UNICODE_AWARE} option is set to true).
*/
public static final String TRANSPOSITIONS = "transpositions";
/**
* Length of common (non-fuzzy) prefix for the suggestions
* in bytes or Unicode code points (if {@link #UNICODE_AWARE} option is set to true).
*/
public static final String NON_FUZZY_PREFIX = "nonFuzzyPrefix";
/**
* Minimum length of lookup key before any edits are allowed for the suggestions
* in bytes or Unicode code points (if {@link #UNICODE_AWARE} option is set to true).
*/
public static final String MIN_FUZZY_LENGTH = "minFuzzyLength";
/**
* File name for the automaton.
*/
private static final String FILENAME = "fwfsta.bin";
@Override
public Lookup create(@SuppressWarnings({"rawtypes"})NamedList params, SolrCore core) {
// mandatory parameter
Object fieldTypeName = params.get(AnalyzingLookupFactory.QUERY_ANALYZER);
if (fieldTypeName == null) {
throw new IllegalArgumentException("Error in configuration: " + AnalyzingLookupFactory.QUERY_ANALYZER + " parameter is mandatory");
}
// retrieve index and query analyzers for the field
FieldType ft = core.getLatestSchema().getFieldTypeByName(fieldTypeName.toString());
if (ft == null) {
throw new IllegalArgumentException("Error in configuration: " + fieldTypeName.toString() + " is not defined in the schema");
}
Analyzer indexAnalyzer = ft.getIndexAnalyzer();
Analyzer queryAnalyzer = ft.getQueryAnalyzer();
// optional parameters
boolean exactMatchFirst = (params.get(AnalyzingLookupFactory.EXACT_MATCH_FIRST) != null)
? Boolean.valueOf(params.get(AnalyzingLookupFactory.EXACT_MATCH_FIRST).toString())
: true;
boolean preserveSep = (params.get(AnalyzingLookupFactory.PRESERVE_SEP) != null)
? Boolean.valueOf(params.get(AnalyzingLookupFactory.PRESERVE_SEP).toString())
: true;
int options = 0;
if (exactMatchFirst) {
options |= FuzzySuggester.EXACT_FIRST;
}
if (preserveSep) {
options |= FuzzySuggester.PRESERVE_SEP;
}
int maxSurfaceFormsPerAnalyzedForm = (params.get(AnalyzingLookupFactory.MAX_SURFACE_FORMS) != null)
? Integer.parseInt(params.get(AnalyzingLookupFactory.MAX_SURFACE_FORMS).toString())
: 256;
int maxGraphExpansions = (params.get(AnalyzingLookupFactory.MAX_EXPANSIONS) != null)
? Integer.parseInt(params.get(AnalyzingLookupFactory.MAX_EXPANSIONS).toString())
: -1;
boolean preservePositionIncrements = params.get(AnalyzingLookupFactory.PRESERVE_POSITION_INCREMENTS) != null
? Boolean.valueOf(params.get(AnalyzingLookupFactory.PRESERVE_POSITION_INCREMENTS).toString())
: false;
int maxEdits = (params.get(MAX_EDITS) != null)
? Integer.parseInt(params.get(MAX_EDITS).toString())
: FuzzySuggester.DEFAULT_MAX_EDITS;
boolean transpositions = (params.get(TRANSPOSITIONS) != null)
? Boolean.parseBoolean(params.get(TRANSPOSITIONS).toString())
: FuzzySuggester.DEFAULT_TRANSPOSITIONS;
int nonFuzzyPrefix = (params.get(NON_FUZZY_PREFIX) != null)
? Integer.parseInt(params.get(NON_FUZZY_PREFIX).toString())
:FuzzySuggester.DEFAULT_NON_FUZZY_PREFIX;
int minFuzzyLength = (params.get(MIN_FUZZY_LENGTH) != null)
? Integer.parseInt(params.get(MIN_FUZZY_LENGTH).toString())
:FuzzySuggester.DEFAULT_MIN_FUZZY_LENGTH;
boolean unicodeAware = (params.get(UNICODE_AWARE) != null)
? Boolean.valueOf(params.get(UNICODE_AWARE).toString())
: FuzzySuggester.DEFAULT_UNICODE_AWARE;
return new FuzzySuggester(getTempDir(), "suggester", indexAnalyzer, queryAnalyzer, options, maxSurfaceFormsPerAnalyzedForm,
maxGraphExpansions, preservePositionIncrements, maxEdits, transpositions, nonFuzzyPrefix,
minFuzzyLength, unicodeAware);
}
@Override
public String storeFileName() {
return FILENAME;
}
}