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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) 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.base;

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

import com.google.common.annotations.GwtCompatible;
import java.util.Collections;
import java.util.Set;
import javax.annotation.CheckForNull;

/** Implementation of an {@link Optional} containing a reference. */
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class Present extends Optional {
  private final T reference;

  Present(T reference) {
    this.reference = reference;
  }

  @Override
  public boolean isPresent() {
    return true;
  }

  @Override
  public T get() {
    return reference;
  }

  @Override
  public T or(T defaultValue) {
    checkNotNull(defaultValue, "use Optional.orNull() instead of Optional.or(null)");
    return reference;
  }

  @Override
  public Optional or(Optional secondChoice) {
    checkNotNull(secondChoice);
    return this;
  }

  @Override
  public T or(Supplier supplier) {
    checkNotNull(supplier);
    return reference;
  }

  @Override
  public T orNull() {
    return reference;
  }

  @Override
  public Set asSet() {
    return Collections.singleton(reference);
  }

  @Override
  public  Optional transform(Function function) {
    return new Present<>(
        checkNotNull(
            function.apply(reference),
            "the Function passed to Optional.transform() must not return null."));
  }

  @Override
  public boolean equals(@CheckForNull Object object) {
    if (object instanceof Present) {
      Present other = (Present) object;
      return reference.equals(other.reference);
    }
    return false;
  }

  @Override
  public int hashCode() {
    return 0x598df91c + reference.hashCode();
  }

  @Override
  public String toString() {
    return "Optional.of(" + reference + ")";
  }

  private static final long serialVersionUID = 0;
}