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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) 2007 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.eventbus;

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

import com.google.common.base.MoreObjects;

/**
 * Wraps an event that was posted, but which had no subscribers and thus could not be delivered.
 *
 * Registering a DeadEvent subscriber is useful for debugging or logging, as it can detect
 * misconfigurations in a system's event distribution.
 *
 * @author Cliff Biffle
 * @since 10.0
 */
@ElementTypesAreNonnullByDefault
public class DeadEvent {

  private final Object source;
  private final Object event;

  /**
   * Creates a new DeadEvent.
   *
   * @param source object broadcasting the DeadEvent (generally the {@link EventBus}).
   * @param event the event that could not be delivered.
   */
  public DeadEvent(Object source, Object event) {
    this.source = checkNotNull(source);
    this.event = checkNotNull(event);
  }

  /**
   * Returns the object that originated this event (not the object that originated the
   * wrapped event). This is generally an {@link EventBus}.
   *
   * @return the source of this event.
   */
  public Object getSource() {
    return source;
  }

  /**
   * Returns the wrapped, 'dead' event, which the system was unable to deliver to any registered
   * subscriber.
   *
   * @return the 'dead' event that could not be delivered.
   */
  public Object getEvent() {
    return event;
  }

  @Override
  public String toString() {
    return MoreObjects.toStringHelper(this).add("source", source).add("event", event).toString();
  }
}