com.google.common.collect.GenericMapMaker.java Source code

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Here is the source code for com.google.common.collect.GenericMapMaker.java

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/*
 * Copyright (C) 2010 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.Beta;
import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.base.Equivalence;
import com.google.common.base.Function;
import com.google.common.base.MoreObjects;
import com.google.common.collect.MapMaker.RemovalListener;
import com.google.common.collect.MapMaker.RemovalNotification;

import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.TimeUnit;

/**
 * A class exactly like {@link MapMaker}, except restricted in the types of maps it can build.
 * For the most part, you should probably just ignore the existence of this class.
 *
 * @param <K0> the base type for all key types of maps built by this map maker
 * @param <V0> the base type for all value types of maps built by this map maker
 * @author Kevin Bourrillion
 * @since 7.0
 * @deprecated This class existed only to support the generic paramterization necessary for the
 *     caching functionality in {@code MapMaker}. That functionality has been moved to {@link
 *     com.google.common.cache.CacheBuilder}, which is a properly generified class and thus needs no
 *     "Generic" equivalent; simple use {@code CacheBuilder} naturally. For general migration
 *     instructions, see the <a
 *     href="https://github.com/google/guava/wiki/MapMakerMigration">MapMaker Migration
 *     Guide</a>.
 */
@Beta
@Deprecated
@GwtCompatible(emulated = true)
abstract class GenericMapMaker<K0, V0> {
    @GwtIncompatible("To be supported")
    enum NullListener implements RemovalListener<Object, Object> {
        INSTANCE;

        @Override
        public void onRemoval(RemovalNotification<Object, Object> notification) {
        }
    }

    // Set by MapMaker, but sits in this class to preserve the type relationship
    @GwtIncompatible("To be supported")
    RemovalListener<K0, V0> removalListener;

    // No subclasses but our own
    GenericMapMaker() {
    }

    /**
     * See {@link MapMaker#keyEquivalence}.
     */
    @GwtIncompatible("To be supported")
    abstract GenericMapMaker<K0, V0> keyEquivalence(Equivalence<Object> equivalence);

    /**
     * See {@link MapMaker#initialCapacity}.
     */
    public abstract GenericMapMaker<K0, V0> initialCapacity(int initialCapacity);

    /**
     * See {@link MapMaker#maximumSize}.
     */
    abstract GenericMapMaker<K0, V0> maximumSize(int maximumSize);

    /**
     * See {@link MapMaker#concurrencyLevel}.
     */
    public abstract GenericMapMaker<K0, V0> concurrencyLevel(int concurrencyLevel);

    /**
     * See {@link MapMaker#weakKeys}.
     */
    @GwtIncompatible("java.lang.ref.WeakReference")
    public abstract GenericMapMaker<K0, V0> weakKeys();

    /**
     * See {@link MapMaker#weakValues}.
     */
    @GwtIncompatible("java.lang.ref.WeakReference")
    public abstract GenericMapMaker<K0, V0> weakValues();

    /**
     * See {@link MapMaker#softValues}.
     *
     * @deprecated Caching functionality in {@code MapMaker} has been moved to {@link
     *     com.google.common.cache.CacheBuilder}, with {@link #softValues} being replaced by {@link
     *     com.google.common.cache.CacheBuilder#softValues}. Note that {@code CacheBuilder} is simply
     *     an enhanced API for an implementation which was branched from {@code MapMaker}.
     */
    @Deprecated
    @GwtIncompatible("java.lang.ref.SoftReference")
    abstract GenericMapMaker<K0, V0> softValues();

    /**
     * See {@link MapMaker#expireAfterWrite}.
     */
    abstract GenericMapMaker<K0, V0> expireAfterWrite(long duration, TimeUnit unit);

    /**
     * See {@link MapMaker#expireAfterAccess}.
     */
    @GwtIncompatible("To be supported")
    abstract GenericMapMaker<K0, V0> expireAfterAccess(long duration, TimeUnit unit);

    /*
     * Note that MapMaker's removalListener() is not here, because once you're interacting with a
     * GenericMapMaker you've already called that, and shouldn't be calling it again.
     */

    @SuppressWarnings("unchecked") // safe covariant cast
    @GwtIncompatible("To be supported")
    <K extends K0, V extends V0> RemovalListener<K, V> getRemovalListener() {
        return (RemovalListener<K, V>) MoreObjects.firstNonNull(removalListener, NullListener.INSTANCE);
    }

    /**
     * See {@link MapMaker#makeMap}.
     */
    public abstract <K extends K0, V extends V0> ConcurrentMap<K, V> makeMap();

    /**
     * See {@link MapMaker#makeCustomMap}.
     */
    @GwtIncompatible("MapMakerInternalMap")
    abstract <K, V> MapMakerInternalMap<K, V> makeCustomMap();

    /**
     * See {@link MapMaker#makeComputingMap}.
     */
    @Deprecated
    abstract <K extends K0, V extends V0> ConcurrentMap<K, V> makeComputingMap(
            Function<? super K, ? extends V> computingFunction);
}