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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS 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) 2008 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 static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.collect.CollectPreconditions.checkEntryNotNull;

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.concurrent.LazyInit;
import com.google.j2objc.annotations.RetainedWith;
import java.util.function.BiConsumer;
import javax.annotation.CheckForNull;

/**
 * Implementation of {@link ImmutableMap} with exactly one entry.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible(serializable = true, emulated = true)
@SuppressWarnings("serial") // uses writeReplace(), not default serialization
@ElementTypesAreNonnullByDefault
final class SingletonImmutableBiMap extends ImmutableBiMap {

  final transient K singleKey;
  final transient V singleValue;

  SingletonImmutableBiMap(K singleKey, V singleValue) {
    checkEntryNotNull(singleKey, singleValue);
    this.singleKey = singleKey;
    this.singleValue = singleValue;
    this.inverse = null;
  }

  private SingletonImmutableBiMap(K singleKey, V singleValue, ImmutableBiMap inverse) {
    this.singleKey = singleKey;
    this.singleValue = singleValue;
    this.inverse = inverse;
  }

  @Override
  @CheckForNull
  public V get(@CheckForNull Object key) {
    return singleKey.equals(key) ? singleValue : null;
  }

  @Override
  public int size() {
    return 1;
  }

  @Override
  public void forEach(BiConsumer action) {
    checkNotNull(action).accept(singleKey, singleValue);
  }

  @Override
  public boolean containsKey(@CheckForNull Object key) {
    return singleKey.equals(key);
  }

  @Override
  public boolean containsValue(@CheckForNull Object value) {
    return singleValue.equals(value);
  }

  @Override
  boolean isPartialView() {
    return false;
  }

  @Override
  ImmutableSet> createEntrySet() {
    return ImmutableSet.of(Maps.immutableEntry(singleKey, singleValue));
  }

  @Override
  ImmutableSet createKeySet() {
    return ImmutableSet.of(singleKey);
  }

  @CheckForNull private final transient ImmutableBiMap inverse;
  @LazyInit @RetainedWith @CheckForNull private transient ImmutableBiMap lazyInverse;

  @Override
  public ImmutableBiMap inverse() {
    if (inverse != null) {
      return inverse;
    } else {
      // racy single-check idiom
      ImmutableBiMap result = lazyInverse;
      if (result == null) {
        return lazyInverse = new SingletonImmutableBiMap<>(singleValue, singleKey, this);
      } else {
        return result;
      }
    }
  }
}