110 lines
3.8 KiB
Java
110 lines
3.8 KiB
Java
/*
|
|
* Copyright (C) 2007 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 java.io.IOException;
|
|
import java.io.ObjectInputStream;
|
|
import java.io.ObjectOutputStream;
|
|
import java.util.EnumMap;
|
|
import java.util.Iterator;
|
|
|
|
import com.google.common.annotations.GwtCompatible;
|
|
import com.google.common.annotations.GwtIncompatible;
|
|
|
|
/**
|
|
* Multiset implementation backed by an {@link EnumMap}.
|
|
*
|
|
* <p>
|
|
* See the Guava User Guide article on <a href=
|
|
* "http://code.google.com/p/guava-libraries/wiki/NewCollectionTypesExplained#Multiset">
|
|
* {@code Multiset}</a>.
|
|
*
|
|
* @author Jared Levy
|
|
* @since 2.0 (imported from Google Collections Library)
|
|
*/
|
|
@GwtCompatible(emulated = true)
|
|
public final class EnumMultiset<E extends Enum<E>> extends AbstractMapBasedMultiset<E> {
|
|
/** Creates an empty {@code EnumMultiset}. */
|
|
public static <E extends Enum<E>> EnumMultiset<E> create(Class<E> type) {
|
|
return new EnumMultiset<E>(type);
|
|
}
|
|
|
|
/**
|
|
* Creates a new {@code EnumMultiset} containing the specified elements.
|
|
*
|
|
* <p>
|
|
* This implementation is highly efficient when {@code elements} is itself a
|
|
* {@link Multiset}.
|
|
*
|
|
* @param elements the elements that the multiset should contain
|
|
* @throws IllegalArgumentException if {@code elements} is empty
|
|
*/
|
|
public static <E extends Enum<E>> EnumMultiset<E> create(Iterable<E> elements) {
|
|
Iterator<E> iterator = elements.iterator();
|
|
checkArgument(iterator.hasNext(), "EnumMultiset constructor passed empty Iterable");
|
|
EnumMultiset<E> multiset = new EnumMultiset<E>(iterator.next().getDeclaringClass());
|
|
Iterables.addAll(multiset, elements);
|
|
return multiset;
|
|
}
|
|
|
|
/**
|
|
* Returns a new {@code EnumMultiset} instance containing the given elements.
|
|
* Unlike {@link EnumMultiset#create(Iterable)}, this method does not produce an
|
|
* exception on an empty iterable.
|
|
*
|
|
* @since 14.0
|
|
*/
|
|
public static <E extends Enum<E>> EnumMultiset<E> create(Iterable<E> elements, Class<E> type) {
|
|
EnumMultiset<E> result = create(type);
|
|
Iterables.addAll(result, elements);
|
|
return result;
|
|
}
|
|
|
|
private transient Class<E> type;
|
|
|
|
/** Creates an empty {@code EnumMultiset}. */
|
|
private EnumMultiset(Class<E> type) {
|
|
super(WellBehavedMap.wrap(new EnumMap<E, Count>(type)));
|
|
this.type = type;
|
|
}
|
|
|
|
@GwtIncompatible("java.io.ObjectOutputStream")
|
|
private void writeObject(ObjectOutputStream stream) throws IOException {
|
|
stream.defaultWriteObject();
|
|
stream.writeObject(type);
|
|
Serialization.writeMultiset(this, stream);
|
|
}
|
|
|
|
/**
|
|
* @serialData the {@code Class<E>} for the enum type, the number of distinct
|
|
* elements, the first element, its count, the second element, its
|
|
* count, and so on
|
|
*/
|
|
@GwtIncompatible("java.io.ObjectInputStream")
|
|
private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
|
|
stream.defaultReadObject();
|
|
@SuppressWarnings("unchecked") // reading data stored by writeObject
|
|
Class<E> localType = (Class<E>) stream.readObject();
|
|
type = localType;
|
|
setBackingMap(WellBehavedMap.wrap(new EnumMap<E, Count>(type)));
|
|
Serialization.populateMultiset(this, stream);
|
|
}
|
|
|
|
@GwtIncompatible("Not needed in emulated source")
|
|
private static final long serialVersionUID = 0;
|
|
}
|