package votorola.g.web.gwt.event; // Copyright 2012, Michael Allan.  Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Votorola Software"), to deal in the Votorola Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicence, and/or sell copies of the Votorola Software, and to permit persons to whom the Votorola Software is furnished to do so, subject to the following conditions: The preceding copyright notice and this permission notice shall be included in all copies or substantial portions of the Votorola Software. THE VOTOROLA SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE VOTOROLA SOFTWARE OR THE USE OR OTHER DEALINGS IN THE VOTOROLA SOFTWARE.

import com.google.gwt.core.client.Scheduler;
import com.google.gwt.event.shared.GwtEvent;
import com.google.gwt.event.shared.HasHandlers;


/** An event that signals a change.
  */
public final class Change extends GwtEvent<ChangeHandler>
{


    /** The common type key for all change events.
      */
    public static final Type<ChangeHandler> TYPE = new Type<ChangeHandler>();



   // - G w t - E v e n t ----------------------------------------------------------------


    public @Override Type<ChangeHandler> getAssociatedType() { return TYPE; }



    protected @Override void dispatch( final ChangeHandler h ) { h.onChange( Change.this ); }



   // ====================================================================================


    /** A coalescing scheduler for the dispatch of change events.  Call {@linkplain
      * #schedule() schedule}() one or more times to fire a single event in the next
      * dispatch phase.
      */
    public static final class CoalescingGun extends CoalescingSchedulerS
      implements Scheduler.ScheduledCommand
    {

        /** Constructs a new CoalescingGun.
          *
          *     @see #source()
          *     @see #phaser()
          */
        public CoalescingGun( HasHandlers _source, Phaser _phaser )
        {
            super( Scheduler.get(), _phaser );
            source = _source;
            init( CoalescingGun.this );
        }


       // --------------------------------------------------------------------------------


        /** The source from which the change events are to be fired.
          */
        public HasHandlers source() { return source; }


            private final HasHandlers source;


       // - S c h e d u l e r . S c h e d u l e d - C o m m a n d ------------------------


        public void execute() { source.fireEvent( new Change() ); }

    }
}