user/src/com/google/gwt/event/shared/EventBus.java

/*
 * Copyright 2010 Google Inc.
 * 
 * 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.gwt.event.shared;

/**
 * Implemented by objects that dispatch {@link GwtEvent}s.
 */
public interface EventBus extends HasHandlers {

  /**
   * Adds a handler.
   * 
   * @param <H> The type of handler
   * @param type the event type associated with this handler
   * @param handler the handler
   * @return the handler registration, can be stored in order to remove the
   *         handler later
   */
  <H extends EventHandler> HandlerRegistration addHandler(
      GwtEvent.Type<H> type, final H handler);
}