package lambdasinaction.chap6;
import java.util.*;
import java.util.function.*;
import java.util.stream.Collector;
import static java.util.stream.Collector.Characteristics.*;
public class ToListCollector<T> implements Collector<T, List<T>, List<T>> {
@Override
public Supplier<List<T>> supplier() {
return () -> new ArrayList<T>();
}
@Override
public BiConsumer<List<T>, T> accumulator() {
return (list, item) -> list.add(item);
}
@Override
public Function<List<T>, List<T>> finisher() {
return i -> i;
}
@Override
public BinaryOperator<List<T>> combiner() {
return (list1, list2) -> {
list1.addAll(list2);
return list1;
};
}
@Override
public Set<Characteristics> characteristics() {
return Collections.unmodifiableSet(EnumSet.of(IDENTITY_FINISH, CONCURRENT));
}
}