EaglerForge/sources/main/java/com/google/common/collect/EmptyImmutableSetMultimap.java

40 lines
1.2 KiB
Java

/*
* Copyright (C) 2009 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;
/**
* Implementation of {@link ImmutableListMultimap} with no entries.
*
* @author Mike Ward
*/
@GwtCompatible(serializable = true)
class EmptyImmutableSetMultimap extends ImmutableSetMultimap<Object, Object> {
static final EmptyImmutableSetMultimap INSTANCE = new EmptyImmutableSetMultimap();
private EmptyImmutableSetMultimap() {
super(ImmutableMap.<Object, ImmutableSet<Object>>of(), 0, null);
}
private Object readResolve() {
return INSTANCE; // preserve singleton property
}
private static final long serialVersionUID = 0;
}