/*
* 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.
*/
package org.apache.jackrabbit.spi2jcr;
import org.apache.jackrabbit.spi.QueryInfo;
import org.apache.jackrabbit.spi.QValueFactory;
import org.apache.jackrabbit.spi.Name;
import org.apache.jackrabbit.commons.iterator.RangeIteratorAdapter;
import org.apache.jackrabbit.commons.iterator.RangeIteratorDecorator;
import org.apache.jackrabbit.spi.commons.conversion.NamePathResolver;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.jcr.query.QueryResult;
import javax.jcr.query.Row;
import javax.jcr.query.Query;
import javax.jcr.query.qom.QueryObjectModel;
import javax.jcr.query.qom.Source;
import javax.jcr.query.qom.Join;
import javax.jcr.query.qom.Selector;
import javax.jcr.RepositoryException;
import javax.jcr.RangeIterator;
import java.util.NoSuchElementException;
import java.util.List;
import java.util.ArrayList;
/**
* <code>QueryInfoImpl</code> implements a <code>QueryInfo</code> based on a
* JCR {@link javax.jcr.query.QueryResult}.
*/
class QueryInfoImpl implements QueryInfo {
/**
* Logger instance for this class.
*/
private static final Logger log = LoggerFactory.getLogger(QueryInfoImpl.class);
/**
* The underlying query result.
*/
private final QueryResult result;
/**
* The id factory.
*/
private final IdFactoryImpl idFactory;
/**
* The namespace resolver.
*/
private final NamePathResolver resolver;
/**
* The QValue factory.
*/
private final QValueFactory qValueFactory;
/**
* The names of the columns in the query result.
*/
private final String[] columnNames;
/**
* The names of the selectors in the query result.
*/
private final Name[] selectorNames;
/**
* Creates a new query info based on a given <code>result</code>.
*
* @param query the JCR query.
* @param result the JCR query result.
* @param idFactory the id factory.
* @param resolver the name path resolver.
* @param qValueFactory the QValue factory.
* @throws RepositoryException if an error occurs while reading from
* <code>result</code>.
*/
public QueryInfoImpl(Query query,
QueryResult result,
IdFactoryImpl idFactory,
NamePathResolver resolver,
QValueFactory qValueFactory)
throws RepositoryException {
this.result = result;
this.idFactory = idFactory;
this.resolver = resolver;
this.qValueFactory = qValueFactory;
this.columnNames = result.getColumnNames();
this.selectorNames = getSelectorNames(query, result, resolver);
}
/**
* {@inheritDoc}
*/
public RangeIterator getRows() {
try {
return new RangeIteratorDecorator(result.getRows()) {
public Object next() {
try {
return new QueryResultRowImpl(
(Row) super.next(), columnNames, selectorNames,
idFactory, resolver, qValueFactory);
} catch (RepositoryException e) {
log.warn("Exception when creating QueryResultRowImpl: " +
e.getMessage(), e);
throw new NoSuchElementException();
}
}
};
} catch (RepositoryException e) {
return RangeIteratorAdapter.EMPTY;
}
}
/**
* {@inheritDoc}
*/
public String[] getColumnNames() {
String[] names = new String[columnNames.length];
System.arraycopy(columnNames, 0, names, 0, columnNames.length);
return names;
}
private static Name[] getSelectorNames(Query query,
QueryResult result,
NamePathResolver resolver)
throws RepositoryException {
List<String> sn = new ArrayList<String>();
if (query instanceof QueryObjectModel) {
QueryObjectModel qom = (QueryObjectModel) query;
collectSelectorNames(qom.getSource(), sn);
} else {
// TODO
// sn.addAll(Arrays.asList(result.getSelectorNames()));
}
Name[] selectorNames = new Name[sn.size()];
for (int i = 0; i < sn.size(); i++) {
selectorNames[i] = resolver.getQName(sn.get(i));
}
return selectorNames;
}
private static void collectSelectorNames(Source source, List<String> sn) {
if (source instanceof Join) {
collectSelectorNames((Join) source, sn);
} else {
collectSelectorNames((Selector) source, sn);
}
}
private static void collectSelectorNames(Join join, List<String> sn) {
collectSelectorNames(join.getLeft(), sn);
collectSelectorNames(join.getRight(), sn);
}
private static void collectSelectorNames(Selector s, List<String> sn) {
sn.add(s.getSelectorName());
}
}