/**
* Copyright 2014 National University of Ireland, Galway.
*
* This file is part of the SIREn project. Project and contact information:
*
* https://github.com/rdelbru/SIREn
*
* Licensed 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.sindice.siren.qparser.json.parser;
import java.util.Iterator;
import org.apache.lucene.queryparser.flexible.core.nodes.ModifierQueryNode.Modifier;
import org.apache.lucene.queryparser.flexible.core.nodes.QueryNode;
import org.codehaus.jackson.JsonNode;
import org.sindice.siren.qparser.json.ParseException;
import org.sindice.siren.qparser.json.nodes.ArrayQueryNode;
import org.sindice.siren.qparser.json.nodes.DescendantQueryNode;
/**
* Parses a <code>descendant</code> property and returns a {@link ArrayQueryNode}.
*/
public class DescendantPropertyParser extends JsonPropertyParser {
public static final String DESCENDANT_PROPERTY = "descendant";
public DescendantPropertyParser(final JsonNode node, final CharSequence field) {
super(node, field);
}
@Override
String getProperty() {
return DESCENDANT_PROPERTY;
}
@Override
ArrayQueryNode parse() throws ParseException {
final JsonNode value = node.path(DESCENDANT_PROPERTY);
if (!value.isArray()) {
throw new ParseException("Invalid property'" + DESCENDANT_PROPERTY + "': value is not an array");
}
final ArrayQueryNode arrayNode = new ArrayQueryNode();
final Iterator<JsonNode> elements = value.getElements();
while (elements.hasNext()) {
final JsonNode element = elements.next();
// parse occur
final OccurPropertyParser occurParser = new OccurPropertyParser(element, field);
Modifier mod = null;
if (occurParser.isPropertyDefined()) {
mod = occurParser.parse();
}
// parse level
final LevelPropertyParser levelParser = new LevelPropertyParser(element, field);
int level = -1;
if (levelParser.isPropertyDefined()) {
level = levelParser.parse();
}
// check if there is either a node or a twig property and parse it
QueryNode queryNode = null;
if (element.has(NodePropertyParser.NODE_PROPERTY)) {
final NodePropertyParser nodeParser = new NodePropertyParser(element, field);
queryNode = nodeParser.parse();
}
if (element.has(TwigPropertyParser.TWIG_PROPERTY)) {
final TwigPropertyParser twigParser = new TwigPropertyParser(element, field);
queryNode = twigParser.parse();
}
// check if either a node or twig property has been defined
if (queryNode == null) {
throw new ParseException("Invalid property'" + DESCENDANT_PROPERTY + "': one array object does not define a twig or node query");
}
// create a descendant query node and add it to the array query node
arrayNode.add(new DescendantQueryNode(queryNode, mod, level));
}
return arrayNode;
}
}