package org.apache.lucene.search.highlight.custom;
/**
* 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.
*/
import java.io.IOException;
import java.io.StringReader;
import java.util.Map;
import org.apache.lucene.analysis.CharArraySet;
import org.apache.lucene.analysis.MockAnalyzer;
import org.apache.lucene.analysis.MockTokenizer;
import org.apache.lucene.analysis.StopAnalyzer;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.highlight.Highlighter;
import org.apache.lucene.search.highlight.InvalidTokenOffsetsException;
import org.apache.lucene.search.highlight.QueryScorer;
import org.apache.lucene.search.highlight.SimpleFragmenter;
import org.apache.lucene.search.highlight.SimpleHTMLFormatter;
import org.apache.lucene.search.highlight.WeightedSpanTerm;
import org.apache.lucene.search.highlight.WeightedSpanTermExtractor;
import org.apache.lucene.util.LuceneTestCase;
/**
* Tests the extensibility of {@link WeightedSpanTermExtractor} and
* {@link QueryScorer} in a user defined package
*/
public class HighlightCustomQueryTest extends LuceneTestCase {
private static final String FIELD_NAME = "contents";
public void testHighlightCustomQuery() throws IOException,
InvalidTokenOffsetsException {
String s1 = "I call our world Flatland, not because we call it so,";
// Verify that a query against the default field results in text being
// highlighted
// regardless of the field name.
CustomQuery q = new CustomQuery(new Term(FIELD_NAME, "world"));
String expected = "I call our <B>world</B> Flatland, not because we call it so,";
String observed = highlightField(q, "SOME_FIELD_NAME", s1);
if (VERBOSE)
System.out.println("Expected: \"" + expected + "\n" + "Observed: \""
+ observed);
assertEquals(
"Query in the default field results in text for *ANY* field being highlighted",
expected, observed);
// Verify that a query against a named field does not result in any
// highlighting
// when the query field name differs from the name of the field being
// highlighted,
// which in this example happens to be the default field name.
q = new CustomQuery(new Term("text", "world"));
expected = s1;
observed = highlightField(q, FIELD_NAME, s1);
if (VERBOSE)
System.out.println("Expected: \"" + expected + "\n" + "Observed: \""
+ observed);
assertEquals(
"Query in a named field does not result in highlighting when that field isn't in the query",
s1, highlightField(q, FIELD_NAME, s1));
}
/**
* This method intended for use with
* <tt>testHighlightingWithDefaultField()</tt>
*
* @throws InvalidTokenOffsetsException
*/
private static String highlightField(Query query, String fieldName,
String text) throws IOException, InvalidTokenOffsetsException {
TokenStream tokenStream = new MockAnalyzer(random, MockTokenizer.SIMPLE,
true, (CharArraySet) StopAnalyzer.ENGLISH_STOP_WORDS_SET, true).tokenStream(fieldName,
new StringReader(text));
// Assuming "<B>", "</B>" used to highlight
SimpleHTMLFormatter formatter = new SimpleHTMLFormatter();
MyQueryScorer scorer = new MyQueryScorer(query, fieldName, FIELD_NAME);
Highlighter highlighter = new Highlighter(formatter, scorer);
highlighter.setTextFragmenter(new SimpleFragmenter(Integer.MAX_VALUE));
String rv = highlighter.getBestFragments(tokenStream, text, 1,
"(FIELD TEXT TRUNCATED)");
return rv.length() == 0 ? text : rv;
}
public static class MyWeightedSpanTermExtractor extends
WeightedSpanTermExtractor {
public MyWeightedSpanTermExtractor() {
super();
}
public MyWeightedSpanTermExtractor(String defaultField) {
super(defaultField);
}
@Override
protected void extractUnknownQuery(Query query,
Map<String, WeightedSpanTerm> terms) throws IOException {
if (query instanceof CustomQuery) {
extractWeightedTerms(terms, new TermQuery(((CustomQuery) query).term));
}
}
}
public static class MyQueryScorer extends QueryScorer {
public MyQueryScorer(Query query, String field, String defaultField) {
super(query, field, defaultField);
}
@Override
protected WeightedSpanTermExtractor newTermExtractor(String defaultField) {
return defaultField == null ? new MyWeightedSpanTermExtractor()
: new MyWeightedSpanTermExtractor(defaultField);
}
}
@SuppressWarnings("serial")
public static class CustomQuery extends Query {
private final Term term;
public CustomQuery(Term term) {
super();
this.term = term;
}
@Override
public String toString(String field) {
return new TermQuery(term).toString(field);
}
@Override
public Query rewrite(IndexReader reader) throws IOException {
return new TermQuery(term);
}
@Override
public int hashCode() {
final int prime = 31;
int result = super.hashCode();
result = prime * result + ((term == null) ? 0 : term.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (!super.equals(obj))
return false;
if (getClass() != obj.getClass())
return false;
CustomQuery other = (CustomQuery) obj;
if (term == null) {
if (other.term != null)
return false;
} else if (!term.equals(other.term))
return false;
return true;
}
}
}