    001/*
    002 * Copyright (c) 2007-2017 Xplenty, 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
    021package cascading.flow.stream.element;
    022
    023import java.util.Collection;
    024import java.util.Collections;
    025import java.util.HashSet;
    026import java.util.Set;
    027
    028import cascading.flow.FlowProcess;
    029import cascading.flow.FlowProcessWrapper;
    030import cascading.property.ConfigDef;
    031
    032/**
    033 *
    034 */
    035public class ElementFlowProcess extends FlowProcessWrapper
    036  {
    037  private final ConfigDef configDef;
    038  private final ConfigDef.Getter getter;
    039
    040  public ElementFlowProcess( FlowProcess flowProcess, ConfigDef configDef )
    041    {
    042    super( flowProcess );
    043
    044    this.configDef = configDef;
    045    this.getter = new ConfigDef.Getter()
    046    {
    047    @Override
    048    public String update( String key, String value )
    049      {
    050      String result = get( key );
    051
    052      if( result == null )
    053        return value;
    054
    055      if( result.contains( value ) )
    056        return result;
    057
    058      return result + "," + value;
    059      }
    060
    061    @Override
    062    public String get( String key )
    063      {
    064      Object value = getDelegate().getProperty( key );
    065
    066      if( value == null )
    067        return null;
    068
    069      return value.toString();
    070      }
    071    };
    072    }
    073
    074  @Override
    075  public Object getProperty( String key )
    076    {
    077    return configDef.apply( key, getter );
    078    }
    079
    080  @Override
    081  public Collection<String> getPropertyKeys()
    082    {
    083    Set<String> keys = new HashSet<String>();
    084
    085    keys.addAll( getDelegate().getPropertyKeys() );
    086    keys.addAll( configDef.getAllKeys() );
    087
    088    return Collections.unmodifiableSet( keys );
    089    }
    090  }