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SearchQueryMaker.java
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SearchQueryMaker.java
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package org.infinispan.query.dsl.embedded.impl;
import static org.infinispan.query.dsl.embedded.impl.HibernateSearchPropertyHelper.KEY;
import static org.infinispan.query.dsl.embedded.impl.HibernateSearchPropertyHelper.VALUE;
import static org.infinispan.query.logging.Log.CONTAINER;
import java.io.IOException;
import java.io.StringReader;
import java.util.Map;
import java.util.Optional;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.core.WhitespaceAnalyzer;
import org.apache.lucene.analysis.tokenattributes.PositionIncrementAttribute;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.BoostQuery;
import org.apache.lucene.search.RegexpQuery;
import org.hibernate.search.backend.lucene.LuceneBackend;
import org.hibernate.search.backend.lucene.LuceneExtension;
import org.hibernate.search.backend.lucene.search.predicate.dsl.LuceneSearchPredicateFactory;
import org.hibernate.search.engine.backend.common.spi.FieldPaths;
import org.hibernate.search.engine.backend.metamodel.IndexFieldDescriptor;
import org.hibernate.search.engine.backend.metamodel.IndexValueFieldDescriptor;
import org.hibernate.search.engine.search.predicate.SearchPredicate;
import org.hibernate.search.engine.search.predicate.dsl.BooleanPredicateClausesStep;
import org.hibernate.search.engine.search.predicate.dsl.ExistsPredicateOptionsStep;
import org.hibernate.search.engine.search.predicate.dsl.MatchPredicateOptionsStep;
import org.hibernate.search.engine.search.predicate.dsl.PhrasePredicateOptionsStep;
import org.hibernate.search.engine.search.predicate.dsl.PredicateBoostStep;
import org.hibernate.search.engine.search.predicate.dsl.PredicateFinalStep;
import org.hibernate.search.engine.search.predicate.dsl.RangePredicateFieldMoreStep;
import org.hibernate.search.engine.search.predicate.dsl.SimpleQueryFlag;
import org.hibernate.search.engine.search.projection.SearchProjection;
import org.hibernate.search.engine.search.projection.dsl.FieldProjectionValueStep;
import org.hibernate.search.engine.search.projection.dsl.SearchProjectionFactory;
import org.hibernate.search.engine.search.sort.SearchSort;
import org.hibernate.search.engine.search.sort.dsl.CompositeSortComponentsStep;
import org.hibernate.search.engine.search.sort.dsl.FieldSortOptionsStep;
import org.hibernate.search.engine.search.sort.dsl.SearchSortFactory;
import org.hibernate.search.util.common.data.RangeBoundInclusion;
import org.infinispan.objectfilter.SortField;
import org.infinispan.objectfilter.impl.ql.PropertyPath;
import org.infinispan.objectfilter.impl.syntax.AggregationExpr;
import org.infinispan.objectfilter.impl.syntax.AndExpr;
import org.infinispan.objectfilter.impl.syntax.BetweenExpr;
import org.infinispan.objectfilter.impl.syntax.BooleanExpr;
import org.infinispan.objectfilter.impl.syntax.ComparisonExpr;
import org.infinispan.objectfilter.impl.syntax.ConstantBooleanExpr;
import org.infinispan.objectfilter.impl.syntax.ConstantValueExpr;
import org.infinispan.objectfilter.impl.syntax.FullTextBoostExpr;
import org.infinispan.objectfilter.impl.syntax.FullTextOccurExpr;
import org.infinispan.objectfilter.impl.syntax.FullTextRangeExpr;
import org.infinispan.objectfilter.impl.syntax.FullTextRegexpExpr;
import org.infinispan.objectfilter.impl.syntax.FullTextTermExpr;
import org.infinispan.objectfilter.impl.syntax.IsNullExpr;
import org.infinispan.objectfilter.impl.syntax.LikeExpr;
import org.infinispan.objectfilter.impl.syntax.NotExpr;
import org.infinispan.objectfilter.impl.syntax.OrExpr;
import org.infinispan.objectfilter.impl.syntax.PropertyValueExpr;
import org.infinispan.objectfilter.impl.syntax.Visitor;
import org.infinispan.objectfilter.impl.syntax.parser.IckleParsingResult;
import org.infinispan.objectfilter.impl.syntax.parser.ObjectPropertyHelper;
import org.infinispan.query.logging.Log;
import org.infinispan.search.mapper.common.EntityReference;
import org.infinispan.search.mapper.mapping.SearchIndexedEntity;
import org.infinispan.search.mapper.mapping.SearchMapping;
import org.infinispan.search.mapper.scope.SearchScope;
import org.infinispan.search.mapper.session.SearchSession;
import org.jboss.logging.Logger;
/**
* An *Expr {@link Visitor} that transforms a {@link IckleParsingResult} into a {@link SearchQueryParsingResult}.
* <p>
* NOTE: This is not stateless, not threadsafe, so it can only be used for a single transformation at a time.
*
* @author anistor@redhat.com
* @author Fabio Massimo Ercoli
* @since 9.0
*/
public final class SearchQueryMaker<TypeMetadata> implements Visitor<PredicateFinalStep, PredicateFinalStep> {
private static final Log log = Logger.getMessageLogger(Log.class, SearchQueryMaker.class.getName());
private static final char LUCENE_SINGLE_CHARACTER_WILDCARD = '?';
private static final char LUCENE_MULTIPLE_CHARACTERS_WILDCARD = '*';
private static final char LUCENE_WILDCARD_ESCAPE_CHARACTER = '\\';
private final SearchMapping searchMapping;
private final ObjectPropertyHelper<TypeMetadata> propertyHelper;
private Map<String, Object> namedParameters;
private LuceneSearchPredicateFactory predicateFactory;
private SearchIndexedEntity indexedEntity;
SearchQueryMaker(SearchMapping searchMapping, ObjectPropertyHelper<TypeMetadata> propertyHelper) {
this.searchMapping = searchMapping;
this.propertyHelper = propertyHelper;
}
public SearchQueryParsingResult transform(IckleParsingResult<TypeMetadata> parsingResult, Map<String, Object> namedParameters,
Class<?> targetedType, String targetedNamedType) {
if (searchMapping == null) {
throw log.noTypeIsIndexed(parsingResult.getQueryString());
}
this.namedParameters = namedParameters;
SearchSession querySession = searchMapping.getMappingSession();
SearchScope<?> scope = (targetedNamedType == null) ? querySession.scope(targetedType) :
querySession.scope(targetedType, targetedNamedType);
predicateFactory = scope.predicate().extension(LuceneExtension.get());
indexedEntity = (targetedNamedType == null) ? searchMapping.indexedEntity(targetedType) :
searchMapping.indexedEntity(targetedNamedType);
SearchPredicate predicate = makePredicate(parsingResult.getWhereClause()).toPredicate();
SearchProjectionInfo projection = makeProjection(parsingResult.getTargetEntityMetadata(), scope.projection(), parsingResult.getProjections(),
parsingResult.getProjectedTypes());
SearchSort sort = makeSort(scope.sort(), parsingResult.getSortFields());
return new SearchQueryParsingResult(targetedType, targetedNamedType, projection, predicate, sort);
}
private SearchProjectionInfo makeProjection(TypeMetadata typeMetadata, SearchProjectionFactory<EntityReference, ?> projectionFactory,
String[] projections, Class<?>[] projectedTypes) {
if (projections == null || projections.length == 0) {
return SearchProjectionInfo.entity(projectionFactory);
}
if (projections.length == 1) {
if (VALUE.equals(projections[0])) {
return SearchProjectionInfo.entity(projectionFactory);
}
if (KEY.equals(projections[0])) {
return SearchProjectionInfo.entityReference(projectionFactory);
}
boolean isRepeatedProperty = propertyHelper.isRepeatedProperty(typeMetadata, FieldPaths.split(projections[0]));
if (isRepeatedProperty) {
return SearchProjectionInfo.multiField(projectionFactory, projections[0], projectedTypes[0]);
} else {
return SearchProjectionInfo.field(projectionFactory, projections[0], projectedTypes[0]);
}
}
SearchProjection<?>[] searchProjections = new SearchProjection<?>[projections.length];
for (int i = 0; i < projections.length; i++) {
if (VALUE.equals(projections[i])) {
searchProjections[i] = projectionFactory.entity().toProjection();
} else if (KEY.equals(projections[i])) {
searchProjections[i] = projectionFactory.entityReference().toProjection();
} else {
boolean isMultiField = propertyHelper.isRepeatedProperty(typeMetadata, FieldPaths.split(projections[i]));
FieldProjectionValueStep<?, ?> projectionStep = projectionFactory.field(projections[i], projectedTypes[i]);
searchProjections[i] = isMultiField ? projectionStep.multi().toProjection() : projectionStep.toProjection();
}
}
return SearchProjectionInfo.composite(projectionFactory, searchProjections);
}
private SearchSort makeSort(SearchSortFactory sortFactory, SortField[] sortFields) {
if (sortFields == null || sortFields.length == 0) {
return sortFactory.score().toSort();
}
if (sortFields.length == 1) {
return makeSort(sortFactory, sortFields[0]);
}
CompositeSortComponentsStep<?> composite = sortFactory.composite();
for (SortField sortField : sortFields) {
composite.add(makeSort(sortFactory, sortField));
}
return composite.toSort();
}
private SearchSort makeSort(SearchSortFactory sortFactory, SortField sortField) {
FieldSortOptionsStep<?, ?> optionsStep = sortFactory.field(sortField.getPath().asStringPathWithoutAlias());
if (sortField.isAscending()) {
optionsStep.asc();
} else {
optionsStep.desc();
}
return optionsStep.toSort();
}
private PredicateFinalStep makePredicate(BooleanExpr expr) {
return expr == null ? predicateFactory.matchAll() : expr.acceptVisitor(this);
}
@Override
public PredicateFinalStep visit(FullTextOccurExpr fullTextOccurExpr) {
PredicateFinalStep childPredicate = fullTextOccurExpr.getChild().acceptVisitor(this);
switch (fullTextOccurExpr.getOccur()) {
case SHOULD:
return predicateFactory.bool().should(childPredicate);
case MUST:
case FILTER:
return predicateFactory.bool().must(childPredicate);
case MUST_NOT:
return predicateFactory.bool().mustNot(childPredicate);
}
throw new IllegalArgumentException("Unknown boolean occur clause: " + fullTextOccurExpr.getOccur());
}
@Override
public PredicateFinalStep visit(FullTextBoostExpr fullTextBoostExpr) {
BooleanExpr child = fullTextBoostExpr.getChild();
float boost = fullTextBoostExpr.getBoost();
// TODO HSEARCH-3884 Support regexp queries
if (child instanceof FullTextRegexpExpr) {
FullTextRegexpExpr fullTextRegexpExpr = (FullTextRegexpExpr) child;
PropertyValueExpr propertyValueExpr = (PropertyValueExpr) fullTextRegexpExpr.getChild();
String regexp = fullTextRegexpExpr.getRegexp();
// boosting native queries
RegexpQuery nativeRegexQuery = new RegexpQuery(new Term(propertyValueExpr.getPropertyPath().asStringPath(), regexp));
BoostQuery nativeQuery = new BoostQuery(nativeRegexQuery, fullTextBoostExpr.getBoost());
return predicateFactory.fromLuceneQuery(nativeQuery);
}
PredicateFinalStep childPredicate = child.acceptVisitor(this);
if (childPredicate instanceof PredicateBoostStep) {
((PredicateBoostStep) childPredicate).boost(boost);
}
return childPredicate;
}
private boolean isMultiTermText(PropertyPath<?> propertyPath, String text) {
Analyzer analyzer = getAnalyzer(propertyPath);
if (analyzer == null) {
analyzer = new WhitespaceAnalyzer();
}
int terms = 0;
try (TokenStream tokenStream = analyzer.tokenStream(propertyPath.asStringPathWithoutAlias(), new StringReader(text))) {
PositionIncrementAttribute posIncAtt = tokenStream.addAttribute(PositionIncrementAttribute.class);
tokenStream.reset();
while (tokenStream.incrementToken()) {
if (posIncAtt.getPositionIncrement() > 0) {
if (++terms > 1) {
break;
}
}
}
tokenStream.end();
} catch (IOException e) {
// Highly unlikely to happen when reading from a StringReader.
log.error(e);
}
return terms > 1;
}
private Analyzer getAnalyzer(PropertyPath<?> propertyPath) {
Optional<IndexFieldDescriptor> indexFieldDescriptor =
indexedEntity.indexManager().descriptor().field(propertyPath.asStringPath());
if (!indexFieldDescriptor.isPresent()) {
return null;
}
IndexFieldDescriptor fieldDescriptor = indexFieldDescriptor.get();
if (fieldDescriptor.isObjectField()) {
return null;
}
IndexValueFieldDescriptor valueField = fieldDescriptor.toValueField();
Optional<String> analyzerName = valueField.type().analyzerName();
if (!analyzerName.isPresent()) {
return null;
}
LuceneBackend luceneBackend = indexedEntity.indexManager().backend().unwrap(LuceneBackend.class);
Optional<? extends Analyzer> analyzer = luceneBackend.analyzer(analyzerName.get());
if (!analyzer.isPresent()) {
return null;
}
return analyzer.get();
}
@Override
public PredicateFinalStep visit(FullTextTermExpr fullTextTermExpr) {
PropertyValueExpr propertyValueExpr = (PropertyValueExpr) fullTextTermExpr.getChild();
String text = fullTextTermExpr.getTerm();
String absoluteFieldPath = propertyValueExpr.getPropertyPath().asStringPath();
int asteriskPos = text.indexOf(LUCENE_MULTIPLE_CHARACTERS_WILDCARD);
int questionPos = text.indexOf(LUCENE_SINGLE_CHARACTER_WILDCARD);
if (asteriskPos == -1 && questionPos == -1) {
if (isMultiTermText(propertyValueExpr.getPropertyPath(), text)) {
PhrasePredicateOptionsStep<?> result = predicateFactory.phrase().field(absoluteFieldPath).matching(text);
if (fullTextTermExpr.getFuzzySlop() != null) {
// slop 4 phrase
result.slop(fullTextTermExpr.getFuzzySlop());
}
return result;
} else {
MatchPredicateOptionsStep<?> result = predicateFactory.match().field(absoluteFieldPath).matching(text);
if (fullTextTermExpr.getFuzzySlop() != null) {
// fuzzy 4 match
result.fuzzy(fullTextTermExpr.getFuzzySlop());
}
return result;
}
} else {
if (fullTextTermExpr.getFuzzySlop() != null) {
throw CONTAINER.getPrefixWildcardOrRegexpQueriesCannotBeFuzzy(fullTextTermExpr.toQueryString());
}
if (questionPos == -1 && asteriskPos == text.length() - 1) {
// term prefix query
// TODO HSEARCH-3906 use a term prefix predicate
// even if simpleQueryString + prefix flag should work as well
return predicateFactory.simpleQueryString()
.field(absoluteFieldPath).matching(text)
.flags(SimpleQueryFlag.PREFIX);
}
// wildcard query
return predicateFactory.wildcard()
.field(absoluteFieldPath).matching(text);
}
}
@Override
public PredicateFinalStep visit(FullTextRegexpExpr fullTextRegexpExpr) {
PropertyValueExpr propertyValueExpr = (PropertyValueExpr) fullTextRegexpExpr.getChild();
String regexp = fullTextRegexpExpr.getRegexp();
// TODO TODO HSEARCH-3884 Support regexp queries
RegexpQuery nativeQuery = new RegexpQuery(new Term(propertyValueExpr.getPropertyPath().asStringPath(), regexp));
return predicateFactory.fromLuceneQuery(nativeQuery);
}
@Override
public PredicateFinalStep visit(FullTextRangeExpr fullTextRangeExpr) {
PropertyValueExpr propertyValueExpr = (PropertyValueExpr) fullTextRangeExpr.getChild();
String absoluteFieldPath = propertyValueExpr.getPropertyPath().asStringPath();
Object lower = fullTextRangeExpr.getLower();
Object upper = fullTextRangeExpr.getUpper();
boolean includeLower = fullTextRangeExpr.isIncludeLower();
boolean includeUpper = fullTextRangeExpr.isIncludeUpper();
if (lower == null && upper == null) {
return predicateFactory.exists().field(absoluteFieldPath);
}
RangePredicateFieldMoreStep<?, ?> range = predicateFactory.range().field(absoluteFieldPath);
return range.between(
lower, includeLower ? RangeBoundInclusion.INCLUDED : RangeBoundInclusion.EXCLUDED,
upper, includeUpper ? RangeBoundInclusion.INCLUDED : RangeBoundInclusion.EXCLUDED);
}
@Override
public PredicateFinalStep visit(NotExpr notExpr) {
BooleanExpr childExpr = notExpr.getChild();
// not is null => exists
// instead of not ( not ( exists ) )
if (childExpr instanceof IsNullExpr) {
PropertyValueExpr propertyValueExpr = (PropertyValueExpr) ((IsNullExpr) childExpr).getChild();
return predicateFactory.exists().field(propertyValueExpr.getPropertyPath().asStringPath());
}
PredicateFinalStep childPredicate = childExpr.acceptVisitor(this);
return predicateFactory.bool().mustNot(childPredicate);
}
@Override
public PredicateFinalStep visit(OrExpr orExpr) {
BooleanPredicateClausesStep<?> bool = predicateFactory.bool();
for (BooleanExpr c : orExpr.getChildren()) {
PredicateFinalStep clause = c.acceptVisitor(this);
bool.should(clause);
}
return bool;
}
@Override
public PredicateFinalStep visit(AndExpr andExpr) {
BooleanPredicateClausesStep<?> bool = predicateFactory.bool();
for (BooleanExpr c : andExpr.getChildren()) {
PredicateFinalStep clause = c.acceptVisitor(this);
bool.must(clause);
}
return bool;
}
@Override
public PredicateFinalStep visit(IsNullExpr isNullExpr) {
PropertyValueExpr propertyValueExpr = (PropertyValueExpr) isNullExpr.getChild();
ExistsPredicateOptionsStep<?> exists = predicateFactory.exists().field(propertyValueExpr.getPropertyPath().asStringPath());
return predicateFactory.bool().mustNot(exists);
}
@Override
public PredicateFinalStep visit(ComparisonExpr comparisonExpr) {
PropertyValueExpr propertyValueExpr = (PropertyValueExpr) comparisonExpr.getLeftChild();
ConstantValueExpr constantValueExpr = (ConstantValueExpr) comparisonExpr.getRightChild();
Comparable value = constantValueExpr.getConstantValueAs(propertyValueExpr.getPrimitiveType(), namedParameters);
String path = propertyValueExpr.getPropertyPath().asStringPath();
switch (comparisonExpr.getComparisonType()) {
case NOT_EQUAL:
return predicateFactory.bool().mustNot(c -> c.match().field(path).matching(value));
case EQUAL:
return predicateFactory.match().field(path).matching(value);
case LESS:
return predicateFactory.range().field(path).lessThan(value);
case LESS_OR_EQUAL:
return predicateFactory.range().field(path).atMost(value);
case GREATER:
return predicateFactory.range().field(path).greaterThan(value);
case GREATER_OR_EQUAL:
return predicateFactory.range().field(path).atLeast(value);
default:
throw new IllegalStateException("Unexpected comparison type: " + comparisonExpr.getComparisonType());
}
}
@Override
public PredicateFinalStep visit(BetweenExpr betweenExpr) {
PropertyValueExpr propertyValueExpr = (PropertyValueExpr) betweenExpr.getLeftChild();
String path = propertyValueExpr.getPropertyPath().asStringPath();
ConstantValueExpr fromValueExpr = (ConstantValueExpr) betweenExpr.getFromChild();
ConstantValueExpr toValueExpr = (ConstantValueExpr) betweenExpr.getToChild();
Comparable fromValue = fromValueExpr.getConstantValueAs(propertyValueExpr.getPrimitiveType(), namedParameters);
Comparable toValue = toValueExpr.getConstantValueAs(propertyValueExpr.getPrimitiveType(), namedParameters);
return predicateFactory.range().field(path).between(fromValue, toValue);
}
@Override
public PredicateFinalStep visit(LikeExpr likeExpr) {
PropertyValueExpr propertyValueExpr = (PropertyValueExpr) likeExpr.getChild();
StringBuilder lucenePattern = new StringBuilder(likeExpr.getPattern(namedParameters));
// transform 'Like' pattern into Lucene wildcard pattern
boolean isEscaped = false;
for (int i = 0; i < lucenePattern.length(); i++) {
char c = lucenePattern.charAt(i);
if (!isEscaped && c == likeExpr.getEscapeChar()) {
isEscaped = true;
lucenePattern.deleteCharAt(i);
} else {
if (isEscaped) {
isEscaped = false;
} else {
if (c == LikeExpr.MULTIPLE_CHARACTERS_WILDCARD) {
lucenePattern.setCharAt(i, LUCENE_MULTIPLE_CHARACTERS_WILDCARD);
continue;
} else if (c == LikeExpr.SINGLE_CHARACTER_WILDCARD) {
lucenePattern.setCharAt(i, LUCENE_SINGLE_CHARACTER_WILDCARD);
continue;
}
}
if (c == LUCENE_SINGLE_CHARACTER_WILDCARD || c == LUCENE_MULTIPLE_CHARACTERS_WILDCARD) {
lucenePattern.insert(i, LUCENE_WILDCARD_ESCAPE_CHARACTER);
i++;
}
}
}
String path = propertyValueExpr.getPropertyPath().asStringPath();
return predicateFactory.wildcard().field(path).matching(lucenePattern.toString());
}
@Override
public PredicateFinalStep visit(ConstantBooleanExpr constantBooleanExpr) {
return constantBooleanExpr.getValue() ? predicateFactory.matchAll() :
predicateFactory.bool().mustNot(predicateFactory.matchAll());
}
@Override
public PredicateFinalStep visit(ConstantValueExpr constantValueExpr) {
throw new IllegalStateException("This node type should not be visited");
}
@Override
public PredicateFinalStep visit(PropertyValueExpr propertyValueExpr) {
throw new IllegalStateException("This node type should not be visited");
}
@Override
public PredicateFinalStep visit(AggregationExpr aggregationExpr) {
throw new IllegalStateException("This node type should not be visited");
}
}