com.google.common.collect.EmptyImmutableSortedMap Maven / Gradle / Ivy
/*
* Copyright (C) 2012 The Guava Authors
*
* Licensed 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 com.google.common.collect;
import static com.google.common.base.Preconditions.checkNotNull;
import com.google.common.annotations.GwtCompatible;
import java.util.Comparator;
import javax.annotation.Nullable;
/**
* An empty immutable sorted map.
*
* @author Louis Wasserman
*/
@GwtCompatible(emulated = true)
@SuppressWarnings("serial") // uses writeReplace, not default serialization
final class EmptyImmutableSortedMap extends ImmutableSortedMap {
private final transient ImmutableSortedSet keySet;
EmptyImmutableSortedMap(Comparator super K> comparator) {
this.keySet = ImmutableSortedSet.emptySet(comparator);
}
EmptyImmutableSortedMap(
Comparator super K> comparator, ImmutableSortedMap descendingMap) {
super(descendingMap);
this.keySet = ImmutableSortedSet.emptySet(comparator);
}
@Override
public V get(@Nullable Object key) {
return null;
}
@Override
public ImmutableSortedSet keySet() {
return keySet;
}
@Override
public int size() {
return 0;
}
@Override
public boolean isEmpty() {
return true;
}
@Override
public ImmutableCollection values() {
return ImmutableList.of();
}
@Override
public String toString() {
return "{}";
}
@Override
boolean isPartialView() {
return false;
}
@Override
public ImmutableSet> entrySet() {
return ImmutableSet.of();
}
@Override
ImmutableSet> createEntrySet() {
throw new AssertionError("should never be called");
}
@Override
public ImmutableSetMultimap asMultimap() {
return ImmutableSetMultimap.of();
}
@Override
public ImmutableSortedMap headMap(K toKey, boolean inclusive) {
checkNotNull(toKey);
return this;
}
@Override
public ImmutableSortedMap tailMap(K fromKey, boolean inclusive) {
checkNotNull(fromKey);
return this;
}
@Override
ImmutableSortedMap createDescendingMap() {
return new EmptyImmutableSortedMap(Ordering.from(comparator()).reverse(), this);
}
}