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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright (C) 2011 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.cache;

import static com.google.common.base.Preconditions.checkNotNull;

import com.google.common.annotations.Beta;
import com.google.common.annotations.GwtCompatible;
import com.google.common.base.Objects;

import java.util.Map.Entry;

import javax.annotation.Nullable;

/**
 * A notification of the removal of a single entry. The key and/or value may be null if they were
 * already garbage collected.
 *
 * Like other {@code Map.Entry} instances associated with {@code CacheBuilder}, this class holds
 * strong references to the key and value, regardless of the type of references the cache may be
 * using.
 *
 * @author Charles Fry
 * @since 10.0
 */
@Beta
@GwtCompatible
public final class RemovalNotification implements Entry {
  @Nullable private final K key;
  @Nullable private final V value;
  private final RemovalCause cause;

  RemovalNotification(@Nullable K key, @Nullable V value, RemovalCause cause) {
    this.key = key;
    this.value = value;
    this.cause = checkNotNull(cause);
  }

  /**
   * Returns the cause for which the entry was removed.
   */
  public RemovalCause getCause() {
    return cause;
  }

  /**
   * Returns {@code true} if there was an automatic removal due to eviction (the cause is neither
   * {@link RemovalCause#EXPLICIT} nor {@link RemovalCause#REPLACED}).
   */
  public boolean wasEvicted() {
    return cause.wasEvicted();
  }

  @Nullable @Override public K getKey() {
    return key;
  }

  @Nullable @Override public V getValue() {
    return value;
  }

  @Override public final V setValue(V value) {
    throw new UnsupportedOperationException();
  }

  @Override public boolean equals(@Nullable Object object) {
    if (object instanceof Entry) {
      Entry that = (Entry) object;
      return Objects.equal(this.getKey(), that.getKey())
          && Objects.equal(this.getValue(), that.getValue());
    }
    return false;
  }

  @Override public int hashCode() {
    K k = getKey();
    V v = getValue();
    return ((k == null) ? 0 : k.hashCode()) ^ ((v == null) ? 0 : v.hashCode());
  }

  /**
   * Returns a string representation of the form {key}={value}.
   */
  @Override public String toString() {
    return getKey() + "=" + getValue();
  }
  private static final long serialVersionUID = 0;
}