11d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert/* 21d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Copyright (C) 2011 The Guava Authors 31d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 41d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Licensed under the Apache License, Version 2.0 (the "License"); 51d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * you may not use this file except in compliance with the License. 61d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * You may obtain a copy of the License at 71d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 81d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * http://www.apache.org/licenses/LICENSE-2.0 91d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 101d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Unless required by applicable law or agreed to in writing, software 111d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * distributed under the License is distributed on an "AS IS" BASIS, 121d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 131d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * See the License for the specific language governing permissions and 141d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * limitations under the License. 151d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 161d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 171d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertpackage com.google.common.cache; 181d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 191d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport static com.google.common.base.Preconditions.checkNotNull; 201d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 211d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport com.google.common.annotations.Beta; 221d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport com.google.common.base.Objects; 231d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 241d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport java.util.Map.Entry; 251d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 261d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport javax.annotation.Nullable; 271d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 281d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert/** 291d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * A notification of the removal of a single entry. The key and/or value may be null if they were 301d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * already garbage collected. 311d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 321d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * <p>Like other {@code Map.Entry} instances associated with {@code CacheBuilder}, this class holds 331d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * strong references to the key and value, regardless of the type of references the cache may be 341d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * using. 351d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 361d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * @author Charles Fry 371d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * @since 10.0 381d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 391d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert@Beta 401d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertpublic final class RemovalNotification<K, V> implements Entry<K, V> { 411d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Nullable private final K key; 421d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Nullable private final V value; 431d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert private final RemovalCause cause; 441d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 451d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert RemovalNotification(@Nullable K key, @Nullable V value, RemovalCause cause) { 461d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert this.key = key; 471d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert this.value = value; 481d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert this.cause = checkNotNull(cause); 491d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 501d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 511d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert /** 521d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Returns the cause for which the entry was removed. 531d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 541d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public RemovalCause getCause() { 551d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return cause; 561d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 571d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 581d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert /** 591d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Returns {@code true} if there was an automatic removal due to eviction (the cause is neither 601d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * {@link RemovalCause#EXPLICIT} nor {@link RemovalCause#REPLACED}). 611d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 621d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public boolean wasEvicted() { 631d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return cause.wasEvicted(); 641d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 651d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 661d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Nullable @Override public K getKey() { 671d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return key; 681d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 691d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 701d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Nullable @Override public V getValue() { 711d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return value; 721d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 731d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 741d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override public final V setValue(V value){ 751d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert throw new UnsupportedOperationException(); 761d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 771d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 781d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override public boolean equals(@Nullable Object object) { 791d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert if (object instanceof Entry) { 801d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert Entry<?, ?> that = (Entry<?, ?>) object; 811d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return Objects.equal(this.getKey(), that.getKey()) 821d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert && Objects.equal(this.getValue(), that.getValue()); 831d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 841d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return false; 851d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 861d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 871d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override public int hashCode() { 881d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert K k = getKey(); 891d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert V v = getValue(); 901d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return ((k == null) ? 0 : k.hashCode()) ^ ((v == null) ? 0 : v.hashCode()); 911d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 921d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 931d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert /** 941d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Returns a string representation of the form <code>{key}={value}</code>. 951d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 961d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override public String toString() { 971d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return getKey() + "=" + getValue(); 981d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 991d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert private static final long serialVersionUID = 0; 1001d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert} 101