elo/src/main/java/org/apache/commons/graph/elo/DefaultRankingSelector.java

package org.apache.commons.graph.elo;

/*
 * 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.
 */

import static org.apache.commons.graph.utils.Assertions.checkNotNull;

import org.apache.commons.graph.DirectedGraph;

/**
 * TODO Fill me!!
 *  
 * @param <P> The player's type
 */
public final class DefaultRankingSelector<P>
    implements RankingSelector<P>
{

    private final DirectedGraph<P, GameResult> tournamentGraph;

    /**
     * Creates a new instance of {@link DefaultRankingSelector} for gived graph.
     * @param tournamentGraph the graph
     */
    public DefaultRankingSelector( DirectedGraph<P, GameResult> tournamentGraph )
    {
        this.tournamentGraph = tournamentGraph;
    }

    /**
     * {@inheritDoc}
     */
    public KFactorBuilder<P> wherePlayersAreRankedIn( PlayersRank<P> playersRank )
    {
        playersRank = checkNotNull( playersRank, "ELO ranking can not be applied if players can not be ranked!" );
        return new DefaultKFactorBuilder<P>( tournamentGraph, playersRank );
    }

}