[jboss-cvs] jboss-mail/src/calendar/calendarejb/src/java/org/jboss/mail/calendar/util/availability ...

[Aron S. <bi...@gm...>]

  User: asogor  
  Date: 06/07/07 21:48:10

  Added:       src/calendar/calendarejb/src/java/org/jboss/mail/calendar/util/availability 
                        AvailabilityCalculator.java
  Log:
  This is the base for getting suggestion for meeting times
  
  Revision  Changes    Path
  1.1      date: 2006/07/08 01:48:10;  author: asogor;  state: Exp;jboss-mail/src/calendar/calendarejb/src/java/org/jboss/mail/calendar/util/availability/AvailabilityCalculator.java
  
  Index: AvailabilityCalculator.java
  ===================================================================
  package org.jboss.mail.calendar.util.availability;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Calendar;
  import java.util.Date;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.jboss.mail.calendar.data.CalendarEvent;
  import org.jboss.mail.calendar.data.Invite;
  
  /**
   * AvailabilityCalculator is a utility to figure out possible timeslots for a meeting
   * 
   * @author Aron Sogor
   *
   */
  public class AvailabilityCalculator {
  	private Log log = LogFactory.getLog(AvailabilityCalculator.class);
  	
  	/**
  	 * The logic of this calculator is simple:
  	 * 
  	 * Create segments using the increment between start date and end date.
  	 * Check which segments are free, meaning there are no meeting during that segment.
  	 * Find numberOfunits continous free segments.
  	 * Return all event proposals. 
  	 * 
  	 * @param invites all the attendees events
  	 * @param startTime the begining of the search range
  	 * @param endTime the end of the search range
  	 * @param incrementSize the size of an increment in minutes
  	 * @param numberOfunits the number of increments the meeting should last
  	 */
  	public static CalendarEvent[] calculate(Invite[] invites,Date startTime,Date endTime,int incrementSize,int numberOfunits)
  	{
  		return (new AvailabilityCalculator()).calculateEvents(invites,startTime,endTime,incrementSize,numberOfunits);
  	}
  	
  	private CalendarEvent[] calculateEvents(Invite[] invites,Date startTime,Date endTime,int incrementSize,int numberOfunits)
  	{
  		ArrayList<CalendarEvent> result = new ArrayList<CalendarEvent>();
  		
  		if(startTime.after(endTime))
  		{
  			log.warn("Availibilty calculator was passed stared and end date reversed");
  			return new CalendarEvent[0];
  		}
  		
  		double segmentTotal = Math.ceil((startTime.getTime() - endTime.getTime())/(60000 * incrementSize));
  		
  		//generate the segments
  		Segment firstSegment = setupSegments(startTime,endTime,segmentTotal);
          //mark each segment free(true) or busy(false)
  		//check each segment as valid
  		
  		return (CalendarEvent[])result.toArray(new CalendarEvent[0]);
  	}
  	
  	private Segment setupSegments(Date startTime,Date endTime,double segmentTotal)
  	{
  		Segment firstSegment = null;
  		Segment currentSegment = null;
  		for (int segmentCnt = 0; segmentCnt < segmentTotal; segmentCnt++) {
  			if(currentSegment == null)
  			{
  				currentSegment.setNextSegment(new Segment(startTime,endTime,true));
  				firstSegment = currentSegment;
  			}
  			else	
  				currentSegment.setNextSegment(new Segment(startTime,endTime,true));
  			currentSegment = currentSegment.getNextSegment();
  		}
  		return firstSegment;
  	}
  	
  	private class Segment{
  		private Date startTime = null;
  		private Date endTime = null;
  		private boolean isBusy = false;
  		private Segment nextSegment = null;
  		
  		public Date getEndTime() {
  			return endTime;
  		}
  		public void setEndTime(Date endTime) {
  			this.endTime = endTime;
  		}
  		public boolean isBusy() {
  			return isBusy;
  		}
  		public void setBusy(boolean isBusy) {
  			this.isBusy = isBusy;
  		}
  		public Date getStartTime() {
  			return startTime;
  		}
  		public void setStartTime(Date startTime) {
  			this.startTime = startTime;
  		}
  		public Segment getNextSegment() {
  			return nextSegment;
  		}
  		public void setNextSegment(Segment nextSegment) {
  			this.nextSegment = nextSegment;
  		}
  		public Segment(Date startTime, Date endTime, boolean isBusy) {
  			super();
  			// TODO Auto-generated constructor stub
  			this.startTime = startTime;
  			this.endTime = endTime;
  			this.isBusy = isBusy;
  		}
  	}
  }