--- /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.util.ArrayList;
+import java.util.LinkedList;
+import java.util.List;
+
+import org.apache.lucene.search.vectorhighlight.FieldQuery.QueryPhraseMap;
+import org.apache.lucene.search.vectorhighlight.FieldTermStack.TermInfo;
+
+/**
+ * FieldPhraseList has a list of WeightedPhraseInfo that is used by FragListBuilder
+ * to create a FieldFragList object.
+ */
+public class FieldPhraseList {
+
+ LinkedList<WeightedPhraseInfo> phraseList = new LinkedList<WeightedPhraseInfo>();
+
+ /**
+ * create a FieldPhraseList that has no limit on the number of phrases to analyze
+ *
+ * @param fieldTermStack FieldTermStack object
+ * @param fieldQuery FieldQuery object
+ */
+ public FieldPhraseList( FieldTermStack fieldTermStack, FieldQuery fieldQuery){
+ this (fieldTermStack, fieldQuery, Integer.MAX_VALUE);
+ }
+
+ /**
+ * a constructor.
+ *
+ * @param fieldTermStack FieldTermStack object
+ * @param fieldQuery FieldQuery object
+ * @param phraseLimit maximum size of phraseList
+ */
+ public FieldPhraseList( FieldTermStack fieldTermStack, FieldQuery fieldQuery, int phraseLimit){
+ final String field = fieldTermStack.getFieldName();
+
+ LinkedList<TermInfo> phraseCandidate = new LinkedList<TermInfo>();
+ QueryPhraseMap currMap = null;
+ QueryPhraseMap nextMap = null;
+ while( !fieldTermStack.isEmpty() && (phraseList.size() < phraseLimit) )
+ {
+ phraseCandidate.clear();
+
+ TermInfo ti = fieldTermStack.pop();
+ currMap = fieldQuery.getFieldTermMap( field, ti.getText() );
+
+ // if not found, discard top TermInfo from stack, then try next element
+ if( currMap == null ) continue;
+
+ // if found, search the longest phrase
+ phraseCandidate.add( ti );
+ while( true ){
+ ti = fieldTermStack.pop();
+ nextMap = null;
+ if( ti != null )
+ nextMap = currMap.getTermMap( ti.getText() );
+ if( ti == null || nextMap == null ){
+ if( ti != null )
+ fieldTermStack.push( ti );
+ if( currMap.isValidTermOrPhrase( phraseCandidate ) ){
+ addIfNoOverlap( new WeightedPhraseInfo( phraseCandidate, currMap.getBoost(), currMap.getTermOrPhraseNumber() ) );
+ }
+ else{
+ while( phraseCandidate.size() > 1 ){
+ fieldTermStack.push( phraseCandidate.removeLast() );
+ currMap = fieldQuery.searchPhrase( field, phraseCandidate );
+ if( currMap != null ){
+ addIfNoOverlap( new WeightedPhraseInfo( phraseCandidate, currMap.getBoost(), currMap.getTermOrPhraseNumber() ) );
+ break;
+ }
+ }
+ }
+ break;
+ }
+ else{
+ phraseCandidate.add( ti );
+ currMap = nextMap;
+ }
+ }
+ }
+ }
+
+ void addIfNoOverlap( WeightedPhraseInfo wpi ){
+ for( WeightedPhraseInfo existWpi : phraseList ){
+ if( existWpi.isOffsetOverlap( wpi ) ) return;
+ }
+ phraseList.add( wpi );
+ }
+
+ public static class WeightedPhraseInfo {
+
+ String text; // unnecessary member, just exists for debugging purpose
+ List<Toffs> termsOffsets; // usually termsOffsets.size() == 1,
+ // but if position-gap > 1 and slop > 0 then size() could be greater than 1
+ float boost; // query boost
+ int seqnum;
+
+ public WeightedPhraseInfo( LinkedList<TermInfo> terms, float boost ){
+ this( terms, boost, 0 );
+ }
+
+ public WeightedPhraseInfo( LinkedList<TermInfo> terms, float boost, int number ){
+ this.boost = boost;
+ this.seqnum = number;
+ termsOffsets = new ArrayList<Toffs>( terms.size() );
+ TermInfo ti = terms.get( 0 );
+ termsOffsets.add( new Toffs( ti.getStartOffset(), ti.getEndOffset() ) );
+ if( terms.size() == 1 ){
+ text = ti.getText();
+ return;
+ }
+ StringBuilder sb = new StringBuilder();
+ sb.append( ti.getText() );
+ int pos = ti.getPosition();
+ for( int i = 1; i < terms.size(); i++ ){
+ ti = terms.get( i );
+ sb.append( ti.getText() );
+ if( ti.getPosition() - pos == 1 ){
+ Toffs to = termsOffsets.get( termsOffsets.size() - 1 );
+ to.setEndOffset( ti.getEndOffset() );
+ }
+ else{
+ termsOffsets.add( new Toffs( ti.getStartOffset(), ti.getEndOffset() ) );
+ }
+ pos = ti.getPosition();
+ }
+ text = sb.toString();
+ }
+
+ public int getStartOffset(){
+ return termsOffsets.get( 0 ).startOffset;
+ }
+
+ public int getEndOffset(){
+ return termsOffsets.get( termsOffsets.size() - 1 ).endOffset;
+ }
+
+ public boolean isOffsetOverlap( WeightedPhraseInfo other ){
+ int so = getStartOffset();
+ int eo = getEndOffset();
+ int oso = other.getStartOffset();
+ int oeo = other.getEndOffset();
+ if( so <= oso && oso < eo ) return true;
+ if( so < oeo && oeo <= eo ) return true;
+ if( oso <= so && so < oeo ) return true;
+ if( oso < eo && eo <= oeo ) return true;
+ return false;
+ }
+
+ @Override
+ public String toString(){
+ StringBuilder sb = new StringBuilder();
+ sb.append( text ).append( '(' ).append( boost ).append( ")(" );
+ for( Toffs to : termsOffsets ){
+ sb.append( to );
+ }
+ sb.append( ')' );
+ return sb.toString();
+ }
+
+ public static class Toffs {
+ int startOffset;
+ int endOffset;
+ public Toffs( int startOffset, int endOffset ){
+ this.startOffset = startOffset;
+ this.endOffset = endOffset;
+ }
+ public void setEndOffset( int endOffset ){
+ this.endOffset = endOffset;
+ }
+ public int getStartOffset(){
+ return startOffset;
+ }
+ public int getEndOffset(){
+ return endOffset;
+ }
+ @Override
+ public String toString(){
+ StringBuilder sb = new StringBuilder();
+ sb.append( '(' ).append( startOffset ).append( ',' ).append( endOffset ).append( ')' );
+ return sb.toString();
+ }
+ }
+ }
+}
fnp / pylucene.git / blobdiff