*/

package com.google.common.collect;

import static com.google.common.base.Preconditions.checkNotNull;
import static java.util.Collections.singletonMap;
import static java.util.stream.Collectors.collectingAndThen;
import static java.util.stream.Collectors.toMap;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.base.Preconditions;

                .getOrDefault(artifact.getArtifactId(), Collections.emptyMap())
                .values()
                .stream()
                .map(MavenProject::getVersion)
                .collect(Collectors.collectingAndThen(Collectors.toList(), Collections::unmodifiableList));
        if (!versions.isEmpty()) {
            return versions;
        }
        return getAllProjects()

          BinaryOperator<V> mergeFunction) {
    checkNotNull(comparator);
    checkNotNull(keyFunction);
    checkNotNull(valueFunction);
    checkNotNull(mergeFunction);
    return Collectors.collectingAndThen(
        Collectors.toMap(
            keyFunction, valueFunction, mergeFunction, () -> new TreeMap<K, V>(comparator)),
        ImmutableSortedMap::copyOfSorted);
  }