--- /dev/null
+package org.apache.lucene.search.vectorhighlight;
+/**
+ * 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.util.Collections;
+import java.util.LinkedList;
+import java.util.Set;
+
+import org.apache.lucene.analysis.Analyzer;
+import org.apache.lucene.analysis.WhitespaceAnalyzer;
+import org.apache.lucene.document.Document;
+import org.apache.lucene.document.Field;
+import org.apache.lucene.document.Field.Index;
+import org.apache.lucene.document.Field.Store;
+import org.apache.lucene.document.Field.TermVector;
+import org.apache.lucene.index.IndexReader;
+import org.apache.lucene.index.IndexWriter;
+import org.apache.lucene.index.IndexWriterConfig;
+import org.apache.lucene.index.TermFreqVector;
+import org.apache.lucene.index.TermPositionVector;
+import org.apache.lucene.index.TermVectorOffsetInfo;
+import org.apache.lucene.queryParser.QueryParser;
+import org.apache.lucene.search.Query;
+import org.apache.lucene.store.Directory;
+import org.apache.lucene.store.RAMDirectory;
+import org.apache.lucene.util.Version;
+
+/**
+ * <code>FieldTermStack</code> is a stack that keeps query terms in the specified field
+ * of the document to be highlighted.
+ */
+public class FieldTermStack {
+
+ private final String fieldName;
+ LinkedList<TermInfo> termList = new LinkedList<TermInfo>();
+
+ public static void main( String[] args ) throws Exception {
+ Analyzer analyzer = new WhitespaceAnalyzer(Version.LUCENE_CURRENT);
+ QueryParser parser = new QueryParser(Version.LUCENE_CURRENT, "f", analyzer );
+ Query query = parser.parse( "a x:b" );
+ FieldQuery fieldQuery = new FieldQuery( query, true, false );
+
+ Directory dir = new RAMDirectory();
+ IndexWriter writer = new IndexWriter(dir, new IndexWriterConfig(Version.LUCENE_CURRENT, analyzer));
+ Document doc = new Document();
+ doc.add( new Field( "f", "a a a b b c a b b c d e f", Store.YES, Index.ANALYZED, TermVector.WITH_POSITIONS_OFFSETS ) );
+ doc.add( new Field( "f", "b a b a f", Store.YES, Index.ANALYZED, TermVector.WITH_POSITIONS_OFFSETS ) );
+ writer.addDocument( doc );
+ writer.close();
+
+ IndexReader reader = IndexReader.open( dir, true );
+ new FieldTermStack( reader, 0, "f", fieldQuery );
+ reader.close();
+ }
+
+ /**
+ * a constructor.
+ *
+ * @param reader IndexReader of the index
+ * @param docId document id to be highlighted
+ * @param fieldName field of the document to be highlighted
+ * @param fieldQuery FieldQuery object
+ * @throws IOException
+ */
+ public FieldTermStack( IndexReader reader, int docId, String fieldName, final FieldQuery fieldQuery ) throws IOException {
+ this.fieldName = fieldName;
+
+ Set<String> termSet = fieldQuery.getTermSet( fieldName );
+ // just return to make null snippet if un-matched fieldName specified when fieldMatch == true
+ if( termSet == null ) return;
+
+ TermFreqVector tfv = reader.getTermFreqVector( docId, fieldName );
+ if( tfv == null ) return; // just return to make null snippets
+ TermPositionVector tpv = null;
+ try{
+ tpv = (TermPositionVector)tfv;
+ }
+ catch( ClassCastException e ){
+ return; // just return to make null snippets
+ }
+
+
+ for( String term : tpv.getTerms() ){
+ if( !termSet.contains( term ) ) continue;
+ int index = tpv.indexOf( term );
+ TermVectorOffsetInfo[] tvois = tpv.getOffsets( index );
+ if( tvois == null ) return; // just return to make null snippets
+ int[] poss = tpv.getTermPositions( index );
+ if( poss == null ) return; // just return to make null snippets
+ for( int i = 0; i < tvois.length; i++ )
+ termList.add( new TermInfo( term, tvois[i].getStartOffset(), tvois[i].getEndOffset(), poss[i] ) );
+ }
+
+ // sort by position
+ Collections.sort( termList );
+ }
+
+ /**
+ * @return field name
+ */
+ public String getFieldName(){
+ return fieldName;
+ }
+
+ /**
+ * @return the top TermInfo object of the stack
+ */
+ public TermInfo pop(){
+ return termList.poll();
+ }
+
+ /**
+ * @param termInfo the TermInfo object to be put on the top of the stack
+ */
+ public void push( TermInfo termInfo ){
+ // termList.push( termInfo ); // avoid Java 1.6 feature
+ termList.addFirst( termInfo );
+ }
+
+ /**
+ * to know whether the stack is empty
+ *
+ * @return true if the stack is empty, false if not
+ */
+ public boolean isEmpty(){
+ return termList == null || termList.size() == 0;
+ }
+
+ public static class TermInfo implements Comparable<TermInfo>{
+
+ final String text;
+ final int startOffset;
+ final int endOffset;
+ final int position;
+
+ TermInfo( String text, int startOffset, int endOffset, int position ){
+ this.text = text;
+ this.startOffset = startOffset;
+ this.endOffset = endOffset;
+ this.position = position;
+ }
+
+ public String getText(){ return text; }
+ public int getStartOffset(){ return startOffset; }
+ public int getEndOffset(){ return endOffset; }
+ public int getPosition(){ return position; }
+
+ @Override
+ public String toString(){
+ StringBuilder sb = new StringBuilder();
+ sb.append( text ).append( '(' ).append(startOffset).append( ',' ).append( endOffset ).append( ',' ).append( position ).append( ')' );
+ return sb.toString();
+ }
+
+ public int compareTo( TermInfo o ) {
+ return ( this.position - o.position );
+ }
+ }
+}
fnp / pylucene.git / blobdiff