| /* |
| * 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.checkArgument; |
| |
| import com.google.common.annotations.GwtCompatible; |
| import com.google.common.collect.ImmutableMap.IteratorBasedImmutableMap; |
| import java.io.Serializable; |
| import java.util.EnumMap; |
| import org.checkerframework.checker.nullness.compatqual.NullableDecl; |
| |
| /** |
| * Implementation of {@link ImmutableMap} backed by a non-empty {@link java.util.EnumMap}. |
| * |
| * @author Louis Wasserman |
| */ |
| @GwtCompatible(serializable = true, emulated = true) |
| @SuppressWarnings("serial") // we're overriding default serialization |
| final class ImmutableEnumMap<K extends Enum<K>, V> extends IteratorBasedImmutableMap<K, V> { |
| static <K extends Enum<K>, V> ImmutableMap<K, V> asImmutable(EnumMap<K, V> map) { |
| switch (map.size()) { |
| case 0: |
| return ImmutableMap.of(); |
| case 1: |
| Entry<K, V> entry = Iterables.getOnlyElement(map.entrySet()); |
| return ImmutableMap.of(entry.getKey(), entry.getValue()); |
| default: |
| return new ImmutableEnumMap<>(map); |
| } |
| } |
| |
| private final transient EnumMap<K, V> delegate; |
| |
| private ImmutableEnumMap(EnumMap<K, V> delegate) { |
| this.delegate = delegate; |
| checkArgument(!delegate.isEmpty()); |
| } |
| |
| @Override |
| UnmodifiableIterator<K> keyIterator() { |
| return Iterators.unmodifiableIterator(delegate.keySet().iterator()); |
| } |
| |
| @Override |
| public int size() { |
| return delegate.size(); |
| } |
| |
| @Override |
| public boolean containsKey(@NullableDecl Object key) { |
| return delegate.containsKey(key); |
| } |
| |
| @Override |
| public V get(Object key) { |
| return delegate.get(key); |
| } |
| |
| @Override |
| public boolean equals(Object object) { |
| if (object == this) { |
| return true; |
| } |
| if (object instanceof ImmutableEnumMap) { |
| object = ((ImmutableEnumMap<?, ?>) object).delegate; |
| } |
| return delegate.equals(object); |
| } |
| |
| @Override |
| UnmodifiableIterator<Entry<K, V>> entryIterator() { |
| return Maps.unmodifiableEntryIterator(delegate.entrySet().iterator()); |
| } |
| |
| @Override |
| boolean isPartialView() { |
| return false; |
| } |
| |
| // All callers of the constructor are restricted to <K extends Enum<K>>. |
| @Override |
| Object writeReplace() { |
| return new EnumSerializedForm<>(delegate); |
| } |
| |
| /* |
| * This class is used to serialize ImmutableEnumMap instances. |
| */ |
| private static class EnumSerializedForm<K extends Enum<K>, V> implements Serializable { |
| final EnumMap<K, V> delegate; |
| |
| EnumSerializedForm(EnumMap<K, V> delegate) { |
| this.delegate = delegate; |
| } |
| |
| Object readResolve() { |
| return new ImmutableEnumMap<>(delegate); |
| } |
| |
| private static final long serialVersionUID = 0; |
| } |
| } |