001    /*
002     * Copyright (C) 2010 The Guava Authors
003     *
004     * Licensed under the Apache License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     *      http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS-IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    
017    package com.google.common.collect;
018    
019    import com.google.common.annotations.Beta;
020    import com.google.common.annotations.GwtCompatible;
021    import com.google.common.annotations.GwtIncompatible;
022    import com.google.common.base.Equivalence;
023    import com.google.common.base.Function;
024    import com.google.common.base.Objects;
025    import com.google.common.collect.MapMaker.RemovalListener;
026    import com.google.common.collect.MapMaker.RemovalNotification;
027    
028    import java.util.concurrent.ConcurrentMap;
029    import java.util.concurrent.TimeUnit;
030    
031    /**
032     * A class exactly like {@link MapMaker}, except restricted in the types of maps it can build.
033     * For the most part, you should probably just ignore the existence of this class.
034     *
035     * @param <K0> the base type for all key types of maps built by this map maker
036     * @param <V0> the base type for all value types of maps built by this map maker
037     * @author Kevin Bourrillion
038     * @since 7.0
039     */
040    @Beta
041    @GwtCompatible(emulated = true)
042    public abstract class GenericMapMaker<K0, V0> {
043      @GwtIncompatible("To be supported")
044      enum NullListener implements RemovalListener<Object, Object> {
045        INSTANCE;
046    
047        public void onRemoval(RemovalNotification<Object, Object> notification) {}
048      }
049    
050      // Set by MapMaker, but sits in this class to preserve the type relationship
051      @GwtIncompatible("To be supported")
052      RemovalListener<K0, V0> removalListener;
053    
054      // No subclasses but our own
055      GenericMapMaker() {}
056    
057      /**
058       * See {@link MapMaker#keyEquivalence}.
059       */
060      @GwtIncompatible("To be supported")
061      abstract GenericMapMaker<K0, V0> keyEquivalence(Equivalence<Object> equivalence);
062    
063      /**
064       * See {@link MapMaker#initialCapacity}.
065       */
066      public abstract GenericMapMaker<K0, V0> initialCapacity(int initialCapacity);
067    
068      /**
069       * See {@link MapMaker#maximumSize}.
070       */
071      abstract GenericMapMaker<K0, V0> maximumSize(int maximumSize);
072    
073      /**
074       * See {@link MapMaker#concurrencyLevel}.
075       */
076      public abstract GenericMapMaker<K0, V0> concurrencyLevel(int concurrencyLevel);
077    
078      /**
079       * See {@link MapMaker#weakKeys}.
080       */
081      @GwtIncompatible("java.lang.ref.WeakReference")
082      public abstract GenericMapMaker<K0, V0> weakKeys();
083    
084      /**
085       * See {@link MapMaker#softKeys}.
086       */
087      @Deprecated
088      @GwtIncompatible("java.lang.ref.SoftReference")
089      public abstract GenericMapMaker<K0, V0> softKeys();
090    
091      /**
092       * See {@link MapMaker#weakValues}.
093       */
094      @GwtIncompatible("java.lang.ref.WeakReference")
095      public abstract GenericMapMaker<K0, V0> weakValues();
096    
097      /**
098       * See {@link MapMaker#softValues}.
099       */
100      @GwtIncompatible("java.lang.ref.SoftReference")
101      public abstract GenericMapMaker<K0, V0> softValues();
102    
103      /**
104       * See {@link MapMaker#expireAfterWrite}.
105       */
106      abstract GenericMapMaker<K0, V0> expireAfterWrite(long duration, TimeUnit unit);
107    
108      /**
109       * See {@link MapMaker#expireAfterAccess}.
110       */
111      @GwtIncompatible("To be supported")
112      abstract GenericMapMaker<K0, V0> expireAfterAccess(long duration, TimeUnit unit);
113    
114      /*
115       * Note that MapMaker's removalListener() is not here, because once you're interacting with a
116       * GenericMapMaker you've already called that, and shouldn't be calling it again.
117       */
118    
119      @SuppressWarnings("unchecked") // safe covariant cast
120      @GwtIncompatible("To be supported")
121      <K extends K0, V extends V0> RemovalListener<K, V> getRemovalListener() {
122        return (RemovalListener<K, V>) Objects.firstNonNull(removalListener, NullListener.INSTANCE);
123      }
124    
125      /**
126       * See {@link MapMaker#makeMap}.
127       */
128      public abstract <K extends K0, V extends V0> ConcurrentMap<K, V> makeMap();
129    
130      /**
131       * See {@link MapMaker#makeCustomMap}.
132       */
133      @GwtIncompatible("MapMakerInternalMap")
134      abstract <K, V> MapMakerInternalMap<K, V> makeCustomMap();
135    
136      /**
137       * See {@link MapMaker#makeComputingMap}.
138       */
139      @Deprecated
140      public abstract <K extends K0, V extends V0> ConcurrentMap<K, V> makeComputingMap(
141          Function<? super K, ? extends V> computingFunction);
142    }