/***********************************************************************************************************************
 *
 * Copyright (C) 2012 by the Stratosphere project (http://stratosphere.eu)
 *
 * 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 eu.stratosphere.pact.compiler.operators;

import java.util.Collections;
import java.util.List;

import eu.stratosphere.pact.common.util.FieldList;
import eu.stratosphere.pact.compiler.dataproperties.LocalProperties;
import eu.stratosphere.pact.compiler.dataproperties.RequestedLocalProperties;
import eu.stratosphere.pact.compiler.util.Utils;

/**
 * 
 */
public class CoGroupWithSolutionSetFirstDescriptor extends CoGroupDescriptor {
	
	public CoGroupWithSolutionSetFirstDescriptor(FieldList keys1, FieldList keys2) {
		super(keys1, keys2);
	}
	
	@Override
	protected List<LocalPropertiesPair> createPossibleLocalProperties() {
		RequestedLocalProperties none = new RequestedLocalProperties();
		RequestedLocalProperties sort = new RequestedLocalProperties(Utils.createOrdering(this.keys2));
		return Collections.singletonList(new LocalPropertiesPair(none, sort));
	}
	
	@Override
	public boolean areCoFulfilled(RequestedLocalProperties requested1, RequestedLocalProperties requested2,
			LocalProperties produced1, LocalProperties produced2)
	{
		return true;
	}

	@Override
	public LocalProperties computeLocalProperties(LocalProperties in1, LocalProperties in2) {
		return in2;
	}
}