/*
* Hibernate Search, full-text search for your domain model
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later
* See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
*/
package org.hibernate.search.query.dsl.impl;
import java.util.ArrayList;
import java.util.List;
import org.apache.lucene.search.BooleanClause;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.search.Filter;
import org.apache.lucene.search.MatchAllDocsQuery;
import org.apache.lucene.search.Query;
import org.hibernate.search.exception.AssertionFailure;
import org.hibernate.search.query.dsl.BooleanJunction;
import org.hibernate.search.query.dsl.MustJunction;
/**
* @author Emmanuel Bernard
*/
class BooleanQueryBuilder implements MustJunction {
private final List<BooleanClause> clauses;
private final QueryCustomizer queryCustomizer;
BooleanQueryBuilder() {
clauses = new ArrayList<BooleanClause>( 5 );
queryCustomizer = new QueryCustomizer();
}
@Override
public BooleanJunction not() {
final int lastIndex = clauses.size() - 1;
final BooleanClause last = clauses.get( lastIndex );
if ( ! last.getOccur().equals( BooleanClause.Occur.MUST ) ) {
throw new AssertionFailure( "Cannot negate class: " + last.getOccur() );
}
clauses.set( lastIndex, new BooleanClause( last.getQuery(), BooleanClause.Occur.MUST_NOT ) );
return this;
}
@Override
public BooleanJunction should(Query query) {
clauses.add( new BooleanClause( query, BooleanClause.Occur.SHOULD ) );
return this;
}
@Override
public MustJunction must(Query query) {
clauses.add( new BooleanClause( query, BooleanClause.Occur.MUST ) );
return this;
}
@Override
public MustJunction boostedTo(float boost) {
queryCustomizer.boostedTo( boost );
return this;
}
@Override
public MustJunction withConstantScore() {
queryCustomizer.withConstantScore();
return this;
}
@Override
public MustJunction filteredBy(Filter filter) {
queryCustomizer.filteredBy( filter );
return this;
}
@Override
public Query createQuery() {
final int nbrOfClauses = clauses.size();
if ( nbrOfClauses == 0 ) {
throw new AssertionFailure( "Cannot create an empty boolean query" );
}
else if ( nbrOfClauses == 1 ) {
final BooleanClause uniqueClause = clauses.get( 0 );
if ( uniqueClause.getOccur().equals( BooleanClause.Occur.MUST_NOT ) ) {
//FIXME We have two choices here, raise an exception or combine with an All query. #2 is done atm.
//TODO which normfield to use and how to pass it?
should( new MatchAllDocsQuery() );
}
else {
//optimize
return queryCustomizer.setWrappedQuery( uniqueClause.getQuery() ).createQuery();
}
}
BooleanQuery query = new BooleanQuery();
for ( BooleanClause clause : clauses ) {
query.add( clause );
}
return queryCustomizer.setWrappedQuery( query ).createQuery();
}
}