package com.atlassian.johnson;
   
   import com.atlassian.johnson.event.Event;
   
   import javax.servlet.ServletContext;
   import java.util.Collections;
   import java.util.List;
   import java.util.concurrent.CopyOnWriteArrayList;
   
  /**
   * A default implementation of {@link JohnsonEventContainer} which stores events in a list.
   * <p/>
   * Note: This implementation is thread-safe.
   *
   * @since 2.0
   */
  public class DefaultJohnsonEventContainer implements JohnsonEventContainer
  {
      private final List<Event> events = new CopyOnWriteArrayList<Event>();
  
      /**
       * Adds the provided {@link Event} to the list.
       * 
       * @param event the event to add
       */
      @Override
      public void addEvent(Event event)
      {
          events.add(event);
      }
  
      /**
       * Retrieves an <i>unmodifiable</i> view of the current {@link Event} list.
       * 
       * @return an unmodifiable collection of zero or more events
       */
      @Override
      public List<Event> getEvents()
      {
          return Collections.unmodifiableList(events);
      }
  
      /**
       * Retrieves a flag indicating whether there are any {@link Event}s in the list.
       * 
       * @return {@link true} if the event list is not empty; otherwise, {@code false}
       */
      @Override
      public boolean hasEvents()
      {
          return !events.isEmpty();
      }
  
      /**
       * Removes the provided {@link Event} from the list, if it can be found.
       *
       * @param event the event to remove
       */
      @Override
      public void removeEvent(Event event)
      {
          events.remove(event);
      }
  }