UnmodifiableSortedSetCollector.java
package net.morimekta.collect.collectors;
import net.morimekta.collect.UnmodifiableSet;
import net.morimekta.collect.UnmodifiableSortedSet;
import java.util.Comparator;
import java.util.Set;
import java.util.function.BiConsumer;
import java.util.function.BinaryOperator;
import java.util.function.Function;
import java.util.function.Supplier;
import java.util.stream.Collector;
public class UnmodifiableSortedSetCollector<E> implements Collector<E, UnmodifiableSortedSet.Builder<E>, UnmodifiableSortedSet<E>> {
private final Comparator<? super E> comparator;
public UnmodifiableSortedSetCollector(Comparator<? super E> comparator) {
this.comparator = comparator;
}
@Override
public Supplier<UnmodifiableSortedSet.Builder<E>> supplier() {
return () -> UnmodifiableSortedSet.newBuilderOrderedBy(comparator);
}
@Override
public BiConsumer<UnmodifiableSortedSet.Builder<E>, E> accumulator() {
return UnmodifiableSortedSet.Builder::add;
}
@Override
public BinaryOperator<UnmodifiableSortedSet.Builder<E>> combiner() {
return (b1, b2) -> b1.addAll(b2.build());
}
@Override
public Function<UnmodifiableSortedSet.Builder<E>, UnmodifiableSortedSet<E>> finisher() {
return UnmodifiableSortedSet.Builder::build;
}
@Override
public Set<Characteristics> characteristics() {
return UnmodifiableSet.setOf(Characteristics.UNORDERED);
}
}