/*
* 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.
*/
package org.apache.openjpa.trader.service.slice;
import java.util.List;
import org.apache.openjpa.slice.DistributionPolicy;
import org.apache.openjpa.trader.domain.Sector;
import org.apache.openjpa.trader.domain.Stock;
import org.apache.openjpa.trader.domain.Tradable;
import org.apache.openjpa.trader.domain.Trade;
import org.apache.openjpa.trader.domain.Trader;
/**
* An example of {@link DistributionPolicy distribution policy} that distributes each persistent
* domain instances of OpenTrader model into specific slice based on the {@link Sector} to which
* a {@link Stock} belongs. This policy demonstrates the use case where data is distributed by
* a related property of the instance.
*
* @author Pinaki Poddar
*
*/
public class SectorDistributionPolicy implements DistributionPolicy {
/**
* This distribution policy determines the sector of the stock and
* picks the slice of the given list of slices at ordinal index of the
* enumerated Sector.
*/
public String distribute(Object pc, List<String> slices, Object context) {
Stock stock = null;
if (pc instanceof Tradable) {
stock = ((Tradable)pc).getStock();
} else if (pc instanceof Stock) {
stock = (Stock)pc;
} else if (pc instanceof Trade) {
stock = ((Trade)pc).getStock();
} else if (pc instanceof Trader) {
throw new IllegalArgumentException("Trader should have been replicated");
}
return stock != null ? slices.get(stock.getSector().ordinal()) : null;
}
}