package org.apache.lucene.search.grouping;
/*
* 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 org.apache.lucene.index.IndexReader;
import org.apache.lucene.search.*;
import java.io.IOException;
import java.util.*;
/**
* A base implementation of {@link AbstractAllGroupHeadsCollector} for retrieving the most relevant groups when grouping
* on a string based group field. More specifically this all concrete implementations of this base implementation
* use {@link org.apache.lucene.search.FieldCache.StringIndex}.
*
* @lucene.experimental
*/
public abstract class TermAllGroupHeadsCollector<GH extends AbstractAllGroupHeadsCollector.GroupHead> extends AbstractAllGroupHeadsCollector<GH> {
private static final int DEFAULT_INITIAL_SIZE = 128;
final String groupField;
FieldCache.StringIndex groupIndex;
IndexReader indexReader;
int docBase;
protected TermAllGroupHeadsCollector(String groupField, int numberOfSorts) {
super(numberOfSorts);
this.groupField = groupField;
}
/**
* Creates an <code>AbstractAllGroupHeadsCollector</code> instance based on the supplied arguments.
* This factory method decides with implementation is best suited.
*
* Delegates to {@link #create(String, org.apache.lucene.search.Sort, int)} with an initialSize of 128.
*
* @param groupField The field to group by
* @param sortWithinGroup The sort within each group
* @return an <code>AbstractAllGroupHeadsCollector</code> instance based on the supplied arguments
* @throws IOException If I/O related errors occur
*/
public static AbstractAllGroupHeadsCollector create(String groupField, Sort sortWithinGroup) throws IOException {
return create(groupField, sortWithinGroup, DEFAULT_INITIAL_SIZE);
}
/**
* Creates an <code>AbstractAllGroupHeadsCollector</code> instance based on the supplied arguments.
* This factory method decides with implementation is best suited.
*
* @param groupField The field to group by
* @param sortWithinGroup The sort within each group
* @param initialSize The initial allocation size of the internal int set and group list which should roughly match
* the total number of expected unique groups. Be aware that the heap usage is
* 4 bytes * initialSize.
* @return an <code>AbstractAllGroupHeadsCollector</code> instance based on the supplied arguments
* @throws IOException If I/O related errors occur
*/
public static AbstractAllGroupHeadsCollector create(String groupField, Sort sortWithinGroup, int initialSize) throws IOException {
boolean sortAllScore = true;
boolean sortAllFieldValue = true;
for (SortField sortField : sortWithinGroup.getSort()) {
if (sortField.getType() == SortField.SCORE) {
sortAllFieldValue = false;
} else if (needGeneralImpl(sortField)) {
return new GeneralAllGroupHeadsCollector(groupField, sortWithinGroup);
} else {
sortAllScore = false;
}
}
if (sortAllScore) {
return new ScoreAllGroupHeadsCollector(groupField, sortWithinGroup, initialSize);
} else if (sortAllFieldValue) {
return new OrdAllGroupHeadsCollector(groupField, sortWithinGroup, initialSize);
} else {
return new OrdScoreAllGroupHeadsCollector(groupField, sortWithinGroup, initialSize);
}
}
// Returns when a sort field needs the general impl.
private static boolean needGeneralImpl(SortField sortField) {
int sortType = sortField.getType();
// Note (MvG): We can also make an optimized impl when sorting is SortField.DOC
return sortType != SortField.STRING_VAL && sortType != SortField.STRING && sortType != SortField.SCORE;
}
// A general impl that works for any group sort.
static class GeneralAllGroupHeadsCollector extends TermAllGroupHeadsCollector<GeneralAllGroupHeadsCollector.GroupHead> {
private final Sort sortWithinGroup;
private final Map<String, GroupHead> groups;
private Scorer scorer;
GeneralAllGroupHeadsCollector(String groupField, Sort sortWithinGroup) throws IOException {
super(groupField, sortWithinGroup.getSort().length);
this.sortWithinGroup = sortWithinGroup;
groups = new HashMap<String, GroupHead>();
final SortField[] sortFields = sortWithinGroup.getSort();
for (int i = 0; i < sortFields.length; i++) {
reversed[i] = sortFields[i].getReverse() ? -1 : 1;
}
}
protected void retrieveGroupHeadAndAddIfNotExist(int doc) throws IOException {
final int ord = groupIndex.order[doc];
final String groupValue = ord == 0 ? null : groupIndex.lookup[ord];
GroupHead groupHead = groups.get(groupValue);
if (groupHead == null) {
groupHead = new GroupHead(groupValue, sortWithinGroup, doc);
groups.put(groupValue == null ? null : groupValue, groupHead);
temporalResult.stop = true;
} else {
temporalResult.stop = false;
}
temporalResult.groupHead = groupHead;
}
protected Collection<GroupHead> getCollectedGroupHeads() {
return groups.values();
}
public void setNextReader(IndexReader reader, int docBase) throws IOException {
this.indexReader = reader;
this.docBase = docBase;
groupIndex = FieldCache.DEFAULT.getStringIndex(reader, groupField);
for (GroupHead groupHead : groups.values()) {
for (int i = 0; i < groupHead.comparators.length; i++) {
groupHead.comparators[i].setNextReader(reader, docBase);
}
}
}
public void setScorer(Scorer scorer) throws IOException {
this.scorer = scorer;
for (GroupHead groupHead : groups.values()) {
for (FieldComparator comparator : groupHead.comparators) {
comparator.setScorer(scorer);
}
}
}
class GroupHead extends AbstractAllGroupHeadsCollector.GroupHead<String> {
final FieldComparator[] comparators;
private GroupHead(String groupValue, Sort sort, int doc) throws IOException {
super(groupValue, doc + docBase);
final SortField[] sortFields = sort.getSort();
comparators = new FieldComparator[sortFields.length];
for (int i = 0; i < sortFields.length; i++) {
comparators[i] = sortFields[i].getComparator(1, i);
comparators[i].setNextReader(indexReader, docBase);
comparators[i].setScorer(scorer);
comparators[i].copy(0, doc);
comparators[i].setBottom(0);
}
}
public int compare(int compIDX, int doc) throws IOException {
return comparators[compIDX].compareBottom(doc);
}
public void updateDocHead(int doc) throws IOException {
for (FieldComparator comparator : comparators) {
comparator.copy(0, doc);
comparator.setBottom(0);
}
this.doc = doc + docBase;
}
}
}
// AbstractAllGroupHeadsCollector optimized for ord fields and scores.
static class OrdScoreAllGroupHeadsCollector extends TermAllGroupHeadsCollector<OrdScoreAllGroupHeadsCollector.GroupHead> {
private final SentinelIntSet ordSet;
private final List<GroupHead> collectedGroups;
private final SortField[] fields;
private FieldCache.StringIndex[] sortsIndex;
private Scorer scorer;
private GroupHead[] segmentGroupHeads;
OrdScoreAllGroupHeadsCollector(String groupField, Sort sortWithinGroup, int initialSize) {
super(groupField, sortWithinGroup.getSort().length);
ordSet = new SentinelIntSet(initialSize, -1);
collectedGroups = new ArrayList<GroupHead>(initialSize);
final SortField[] sortFields = sortWithinGroup.getSort();
fields = new SortField[sortFields.length];
sortsIndex = new FieldCache.StringIndex[sortFields.length];
for (int i = 0; i < sortFields.length; i++) {
reversed[i] = sortFields[i].getReverse() ? -1 : 1;
fields[i] = sortFields[i];
}
}
protected Collection<GroupHead> getCollectedGroupHeads() {
return collectedGroups;
}
public void setScorer(Scorer scorer) throws IOException {
this.scorer = scorer;
}
protected void retrieveGroupHeadAndAddIfNotExist(int doc) throws IOException {
int key = groupIndex.order[doc];
GroupHead groupHead;
if (!ordSet.exists(key)) {
ordSet.put(key);
String term = key == 0 ? null : groupIndex.lookup[key];
groupHead = new GroupHead(doc, term);
collectedGroups.add(groupHead);
segmentGroupHeads[key] = groupHead;
temporalResult.stop = true;
} else {
temporalResult.stop = false;
groupHead = segmentGroupHeads[key];
}
temporalResult.groupHead = groupHead;
}
public void setNextReader(IndexReader reader, int docBase) throws IOException {
this.indexReader = reader;
this.docBase = docBase;
groupIndex = FieldCache.DEFAULT.getStringIndex(reader, groupField);
for (int i = 0; i < fields.length; i++) {
if (fields[i].getType() == SortField.SCORE) {
continue;
}
sortsIndex[i] = FieldCache.DEFAULT.getStringIndex(reader, fields[i].getField());
}
// Clear ordSet and fill it with previous encountered groups that can occur in the current segment.
ordSet.clear();
segmentGroupHeads = new GroupHead[groupIndex.lookup.length];
for (GroupHead collectedGroup : collectedGroups) {
int ord = groupIndex.binarySearchLookup(collectedGroup.groupValue);
if (ord >= 0) {
ordSet.put(ord);
segmentGroupHeads[ord] = collectedGroup;
for (int i = 0; i < sortsIndex.length; i++) {
if (fields[i].getType() == SortField.SCORE) {
continue;
}
collectedGroup.sortOrds[i] = sortsIndex[i].binarySearchLookup(collectedGroup.sortValues[i]);
}
}
}
}
class GroupHead extends AbstractAllGroupHeadsCollector.GroupHead<String> {
String[] sortValues;
int[] sortOrds;
float[] scores;
private GroupHead(int doc, String groupValue) throws IOException {
super(groupValue, doc + docBase);
sortValues = new String[sortsIndex.length];
sortOrds = new int[sortsIndex.length];
scores = new float[sortsIndex.length];
for (int i = 0; i < sortsIndex.length; i++) {
if (fields[i].getType() == SortField.SCORE) {
scores[i] = scorer.score();
} else {
sortValues[i] = sortsIndex[i].lookup[sortsIndex[i].order[doc]];
sortOrds[i] = sortsIndex[i].order[doc];
}
}
}
public int compare(int compIDX, int doc) throws IOException {
if (fields[compIDX].getType() == SortField.SCORE) {
float score = scorer.score();
if (scores[compIDX] < score) {
return 1;
} else if (scores[compIDX] > score) {
return -1;
}
return 0;
} else {
if (sortOrds[compIDX] < 0) {
// The current segment doesn't contain the sort value we encountered before. Therefore the ord is negative.
final String val1 = sortValues[compIDX];
final String val2 = sortsIndex[compIDX].lookup[sortsIndex[compIDX].order[doc]];
if (val1 == null) {
if (val2 == null) {
return 0;
}
return -1;
} else if (val2 == null) {
return 1;
}
return val1.compareTo(val2);
} else {
return sortOrds[compIDX] - sortsIndex[compIDX].order[doc];
}
}
}
public void updateDocHead(int doc) throws IOException {
for (int i = 0; i < sortsIndex.length; i++) {
if (fields[i].getType() == SortField.SCORE) {
scores[i] = scorer.score();
} else {
sortValues[i] = sortsIndex[i].lookup[sortsIndex[i].order[doc]];
sortOrds[i] = sortsIndex[i].order[doc];
}
}
this.doc = doc + docBase;
}
}
}
// AbstractAllGroupHeadsCollector optimized for ord fields.
static class OrdAllGroupHeadsCollector extends TermAllGroupHeadsCollector<OrdAllGroupHeadsCollector.GroupHead> {
private final SentinelIntSet ordSet;
private final List<GroupHead> collectedGroups;
private final SortField[] fields;
private FieldCache.StringIndex[] sortsIndex;
private GroupHead[] segmentGroupHeads;
OrdAllGroupHeadsCollector(String groupField, Sort sortWithinGroup, int initialSize) {
super(groupField, sortWithinGroup.getSort().length);
ordSet = new SentinelIntSet(initialSize, -1);
collectedGroups = new ArrayList<GroupHead>(initialSize);
final SortField[] sortFields = sortWithinGroup.getSort();
fields = new SortField[sortFields.length];
sortsIndex = new FieldCache.StringIndex[sortFields.length];
for (int i = 0; i < sortFields.length; i++) {
reversed[i] = sortFields[i].getReverse() ? -1 : 1;
fields[i] = sortFields[i];
}
}
protected Collection<GroupHead> getCollectedGroupHeads() {
return collectedGroups;
}
public void setScorer(Scorer scorer) throws IOException {
}
protected void retrieveGroupHeadAndAddIfNotExist(int doc) throws IOException {
int key = groupIndex.order[doc];
GroupHead groupHead;
if (!ordSet.exists(key)) {
ordSet.put(key);
String term = key == 0 ? null : groupIndex.lookup[key];
groupHead = new GroupHead(doc, term);
collectedGroups.add(groupHead);
segmentGroupHeads[key] = groupHead;
temporalResult.stop = true;
} else {
temporalResult.stop = false;
groupHead = segmentGroupHeads[key];
}
temporalResult.groupHead = groupHead;
}
public void setNextReader(IndexReader reader, int docBase) throws IOException {
this.indexReader = reader;
this.docBase = docBase;
groupIndex = FieldCache.DEFAULT.getStringIndex(reader, groupField);
for (int i = 0; i < fields.length; i++) {
sortsIndex[i] = FieldCache.DEFAULT.getStringIndex(reader, fields[i].getField());
}
// Clear ordSet and fill it with previous encountered groups that can occur in the current segment.
ordSet.clear();
segmentGroupHeads = new GroupHead[groupIndex.lookup.length];
for (GroupHead collectedGroup : collectedGroups) {
int groupOrd = groupIndex.binarySearchLookup(collectedGroup.groupValue);
if (groupOrd >= 0) {
ordSet.put(groupOrd);
segmentGroupHeads[groupOrd] = collectedGroup;
for (int i = 0; i < sortsIndex.length; i++) {
collectedGroup.sortOrds[i] = sortsIndex[i].binarySearchLookup(collectedGroup.sortValues[i]);
}
}
}
}
class GroupHead extends AbstractAllGroupHeadsCollector.GroupHead<String> {
String[] sortValues;
int[] sortOrds;
private GroupHead(int doc, String groupValue) throws IOException {
super(groupValue, doc + docBase);
sortValues = new String[sortsIndex.length];
sortOrds = new int[sortsIndex.length];
for (int i = 0; i < sortsIndex.length; i++) {
sortValues[i] = sortsIndex[i].lookup[sortsIndex[i].order[doc]];
sortOrds[i] = sortsIndex[i].order[doc];
}
}
public int compare(int compIDX, int doc) throws IOException {
if (sortOrds[compIDX] < 0) {
// The current segment doesn't contain the sort value we encountered before. Therefore the ord is negative.
final String val1 = sortValues[compIDX];
final String val2 = sortsIndex[compIDX].lookup[sortsIndex[compIDX].order[doc]];
if (val1 == null) {
if (val2 == null) {
return 0;
}
return -1;
} else if (val2 == null) {
return 1;
}
return val1.compareTo(val2);
} else {
return sortOrds[compIDX] - sortsIndex[compIDX].order[doc];
}
}
public void updateDocHead(int doc) throws IOException {
for (int i = 0; i < sortsIndex.length; i++) {
sortValues[i] = sortsIndex[i].lookup[sortsIndex[i].order[doc]];
sortOrds[i] = sortsIndex[i].order[doc];
}
this.doc = doc + docBase;
}
}
}
// AbstractAllGroupHeadsCollector optimized for scores.
static class ScoreAllGroupHeadsCollector extends TermAllGroupHeadsCollector<ScoreAllGroupHeadsCollector.GroupHead> {
private final SentinelIntSet ordSet;
private final List<GroupHead> collectedGroups;
private final SortField[] fields;
private Scorer scorer;
private GroupHead[] segmentGroupHeads;
ScoreAllGroupHeadsCollector(String groupField, Sort sortWithinGroup, int initialSize) {
super(groupField, sortWithinGroup.getSort().length);
ordSet = new SentinelIntSet(initialSize, -1);
collectedGroups = new ArrayList<GroupHead>(initialSize);
final SortField[] sortFields = sortWithinGroup.getSort();
fields = new SortField[sortFields.length];
for (int i = 0; i < sortFields.length; i++) {
reversed[i] = sortFields[i].getReverse() ? -1 : 1;
fields[i] = sortFields[i];
}
}
protected Collection<GroupHead> getCollectedGroupHeads() {
return collectedGroups;
}
public void setScorer(Scorer scorer) throws IOException {
this.scorer = scorer;
}
protected void retrieveGroupHeadAndAddIfNotExist(int doc) throws IOException {
int key = groupIndex.order[doc];
GroupHead groupHead;
if (!ordSet.exists(key)) {
ordSet.put(key);
String term = key == 0 ? null : groupIndex.lookup[key];
groupHead = new GroupHead(doc, term);
collectedGroups.add(groupHead);
segmentGroupHeads[key] = groupHead;
temporalResult.stop = true;
} else {
temporalResult.stop = false;
groupHead = segmentGroupHeads[key];
}
temporalResult.groupHead = groupHead;
}
public void setNextReader(IndexReader reader, int docBase) throws IOException {
this.indexReader = reader;
this.docBase = docBase;
groupIndex = FieldCache.DEFAULT.getStringIndex(reader, groupField);
// Clear ordSet and fill it with previous encountered groups that can occur in the current segment.
ordSet.clear();
segmentGroupHeads = new GroupHead[groupIndex.lookup.length];
for (GroupHead collectedGroup : collectedGroups) {
int ord = groupIndex.binarySearchLookup(collectedGroup.groupValue);
if (ord >= 0) {
ordSet.put(ord);
segmentGroupHeads[ord] = collectedGroup;
}
}
}
class GroupHead extends AbstractAllGroupHeadsCollector.GroupHead<String> {
float[] scores;
private GroupHead(int doc, String groupValue) throws IOException {
super(groupValue, doc + docBase);
scores = new float[fields.length];
float score = scorer.score();
for (int i = 0; i < scores.length; i++) {
scores[i] = score;
}
}
public int compare(int compIDX, int doc) throws IOException {
float score = scorer.score();
if (scores[compIDX] < score) {
return 1;
} else if (scores[compIDX] > score) {
return -1;
}
return 0;
}
public void updateDocHead(int doc) throws IOException {
float score = scorer.score();
for (int i = 0; i < scores.length; i++) {
scores[i] = score;
}
this.doc = doc + docBase;
}
}
}
}