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This project includes GWT-friendly sources.
/*
* Copyright (C) 2011 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 com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import java.io.Serializable;
import java.util.NoSuchElementException;
import java.util.Set;
import javax.annotation.CheckForNull;
/**
* An empty contiguous set.
*
* @author Gregory Kick
*/
@GwtCompatible(emulated = true)
@SuppressWarnings("rawtypes") // allow ungenerified Comparable types
@ElementTypesAreNonnullByDefault
final class EmptyContiguousSet extends ContiguousSet {
EmptyContiguousSet(DiscreteDomain domain) {
super(domain);
}
@Override
public C first() {
throw new NoSuchElementException();
}
@Override
public C last() {
throw new NoSuchElementException();
}
@Override
public int size() {
return 0;
}
@Override
public ContiguousSet intersection(ContiguousSet other) {
return this;
}
@Override
public Range range() {
throw new NoSuchElementException();
}
@Override
public Range range(BoundType lowerBoundType, BoundType upperBoundType) {
throw new NoSuchElementException();
}
@Override
ContiguousSet headSetImpl(C toElement, boolean inclusive) {
return this;
}
@Override
ContiguousSet subSetImpl(
C fromElement, boolean fromInclusive, C toElement, boolean toInclusive) {
return this;
}
@Override
ContiguousSet tailSetImpl(C fromElement, boolean fromInclusive) {
return this;
}
@Override
public boolean contains(@CheckForNull Object object) {
return false;
}
@GwtIncompatible // not used by GWT emulation
@Override
int indexOf(@CheckForNull Object target) {
return -1;
}
@Override
public UnmodifiableIterator iterator() {
return Iterators.emptyIterator();
}
@GwtIncompatible // NavigableSet
@Override
public UnmodifiableIterator descendingIterator() {
return Iterators.emptyIterator();
}
@Override
boolean isPartialView() {
return false;
}
@Override
public boolean isEmpty() {
return true;
}
@Override
public ImmutableList asList() {
return ImmutableList.of();
}
@Override
public String toString() {
return "[]";
}
@Override
public boolean equals(@CheckForNull Object object) {
if (object instanceof Set) {
Set that = (Set) object;
return that.isEmpty();
}
return false;
}
@GwtIncompatible // not used in GWT
@Override
boolean isHashCodeFast() {
return true;
}
@Override
public int hashCode() {
return 0;
}
@GwtIncompatible // serialization
private static final class SerializedForm implements Serializable {
private final DiscreteDomain domain;
private SerializedForm(DiscreteDomain domain) {
this.domain = domain;
}
private Object readResolve() {
return new EmptyContiguousSet(domain);
}
private static final long serialVersionUID = 0;
}
@GwtIncompatible // serialization
@Override
Object writeReplace() {
return new SerializedForm(domain);
}
@GwtIncompatible // NavigableSet
@Override
ImmutableSortedSet createDescendingSet() {
return ImmutableSortedSet.emptySet(Ordering.natural().reverse());
}
}