/*******************************************************************************
* Copyright 2014 University of Southern California
*
* 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.
*
* This code was developed by the Information Integration Group as part
* of the Karma project at the Information Sciences Institute of the
* University of Southern California. For more information, publications,
* and related projects, please see: http://www.isi.edu/integration
******************************************************************************/
package edu.isi.karma.kr2rml.planning;
import java.util.Set;
import edu.isi.karma.kr2rml.template.ColumnTemplateTerm;
public class WorksheetDepthRootStrategy extends RootStrategy {
public WorksheetDepthRootStrategy()
{
super(new RootStrategy());
}
public WorksheetDepthRootStrategy(
RootStrategy backupStrategy) {
super(backupStrategy);
}
@Override
public String findRoot(TriplesMapGraph graph) {
Set<String> triplesMapIds = graph.getTriplesMapIds();
int minDepth = Integer.MAX_VALUE;
String root = null;
for(String triplesMapId : triplesMapIds)
{
TriplesMap map = graph.getTriplesMap(triplesMapId);
int depth = ColumnTemplateTerm.calculateMaximumColumnPathLength(map.getSubject().getTemplate().getAllColumnNameTermElements());
if(depth < minDepth)
{
minDepth = depth;
root = triplesMapId;
}
}
if(root == null)
{
return backupStrategy.findRoot(graph);
}
return root;
}
}