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/*
 * Copyright (C) 2008 Google Inc.
 *
 * 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 org.fakereplace.com.google.common.collect;

import java.util.Map;

import org.fakereplace.com.google.common.annotations.GwtCompatible;


/**
 * An empty immutable map.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible(serializable = true)
final class EmptyImmutableMap extends ImmutableMap {
    static final EmptyImmutableMap INSTANCE = new EmptyImmutableMap();

    private EmptyImmutableMap() {
    }

    @Override
    public Object get(Object key) {
        return null;
    }

    public int size() {
        return 0;
    }

    @Override
    public boolean isEmpty() {
        return true;
    }

    @Override
    public boolean containsKey(Object key) {
        return false;
    }

    @Override
    public boolean containsValue(Object value) {
        return false;
    }

    @Override
    public ImmutableSet> entrySet() {
        return ImmutableSet.of();
    }

    @Override
    public ImmutableSet