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package bjc.utils.funcutils;
import java.util.stream.Collector;
import bjc.data.Holder;
import bjc.data.Pair;
/**
* Utilities for producing implementations of {@link Collector}
*
* @author ben
*/
public class CollectorUtils {
/**
* Create a collector that applies two collectors at once.
*
* @param <InitialType>
* The type of the collection to collect from.
*
* @param <AuxType1>
* The intermediate type of the first collector.
*
* @param <AuxType2>
* The intermediate type of the second collector.
*
* @param <FinalType1>
* The final type of the first collector.
*
* @param <FinalType2>
* The final type of the second collector.
*
* @param first
* The first collector to use.
*
* @param second
* The second collector to use.
*
* @return A collector that functions as mentioned above.
*/
public static <InitialType, AuxType1, AuxType2, FinalType1, FinalType2>
Collector<InitialType, Holder<Pair<AuxType1, AuxType2>>,
Pair<FinalType1, FinalType2>>
compoundCollect(final Collector<InitialType, AuxType1, FinalType1> first,
final Collector<InitialType, AuxType2, FinalType2> second) {
return new CompoundCollector<>(first, second);
}
}
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