    001/*
    002 * Copyright (c) 2007-2016 Concurrent, Inc. All Rights Reserved.
    003 *
    004 * Project and contact information: http://www.cascading.org/
    005 *
    006 * This file is part of the Cascading project.
    007 *
    008 * Licensed under the Apache License, Version 2.0 (the "License");
    009 * you may not use this file except in compliance with the License.
    010 * You may obtain a copy of the License at
    011 *
    012 *     http://www.apache.org/licenses/LICENSE-2.0
    013 *
    014 * Unless required by applicable law or agreed to in writing, software
    015 * distributed under the License is distributed on an "AS IS" BASIS,
    016 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    017 * See the License for the specific language governing permissions and
    018 * limitations under the License.
    019 */
    020
    021/*
    022 * See package LICENSE.txt for additional license information.
    023 */
    024
    025package cascading.util.jgrapht;
    026
    027import java.util.HashMap;
    028import java.util.Map;
    029
    030public class IntegerNameProvider<V> implements VertexNameProvider<V>
    031  {
    032  private int nextID = 1;
    033  private final Map<V, Integer> idMap = new HashMap<>();
    034
    035  public void clear()
    036    {
    037    nextID = 1;
    038    idMap.clear();
    039    }
    040
    041  @Override
    042  public String getVertexName( V vertex )
    043    {
    044    Integer id = idMap.get( vertex );
    045
    046    if( id == null )
    047      {
    048      id = nextID++;
    049      idMap.put( vertex, id );
    050      }
    051
    052    return id.toString();
    053    }
    054  }