SingleTemporalCollection.java

/*
Name: 
    - SingleTemporalCollection 

Description: 
    -  

Requires:
    - 
    
Provides:
    - 

Part of: ProcessPuzzle Framework, Domain and Business Model Ready Architecture. Provides content, workflow and social networking functionality. 
http://www.processpuzzle.com

ProcessPuzzle - Content and Workflow Management Integration Business Platform

Author(s): 
    - Zsolt Zsuffa

Copyright: (C) 2011 This program is free software: you can redistribute it and/or modify it under the terms of the 
GNU General Public License as published by the Free Software Foundation, either version 3 of the License, 
or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

package com.processpuzzle.util.domain;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import com.processpuzzle.fundamental_types.domain.TimePoint;

public class SingleTemporalCollection extends TemporalCollection {
   private Map<TimePoint, Object> contents = new HashMap<TimePoint, Object>();

   public Object get( TimePoint when ) {
      Iterator<TimePoint> it = milestones().iterator();
      while( it.hasNext() ){
         TimePoint thisDate = it.next();
         if( thisDate.before( when ) || thisDate.equals( when ) )
            return contents.get( thisDate );
      }
      throw new IllegalArgumentException( "no records that early" );
   }

   public void put( TimePoint at, Object item ) {
      contents.put( at, item );
      clearMilestoneCache();
   }

   private List<TimePoint> _milestoneCache;

   private List<TimePoint> milestones() {
      if( _milestoneCache == null )
         calculateMilestones();
      return _milestoneCache;
   }

   private void calculateMilestones() {
      _milestoneCache = new ArrayList<TimePoint>( contents.size() );
      _milestoneCache.addAll( contents.keySet() );
      Collections.sort( _milestoneCache, Collections.reverseOrder() );
   }

   private void clearMilestoneCache() {
      _milestoneCache = null;
   }

   public Object get( int year, int month, int date ) {
      return get( new TimePoint( year, month, date ) );
   }

   public Object get() {
      return get( TimePoint.today() );
   }

   public void put( Object item ) {
      put( TimePoint.today(), item );
   }

   public TemporalCollection copy() {
      SingleTemporalCollection result = new SingleTemporalCollection();
      result.contents.putAll( this.contents );
      return result;
   }
}