@Override
	public WorkSheetHandle[] getWorkSheets()
	{
		try
		{
			if( myfactory != null )
			{
				int numsheets = mybook.getNumWorkSheets();
				if( numsheets == 0 )
				{
					throw new WorkSheetNotFoundException( "WorkBook has No Sheets." );
				}
				WorkSheetHandle[] sheets = new WorkSheetHandle[numsheets];
				for( int i = 0; i < numsheets; i++ )
				{
					Boundsheet bs = mybook.getWorkSheetByNumber( i );
					bs.setWorkBook( mybook );
					sheets[i] = new WorkSheetHandle( bs, this );
				}
				return sheets;
			}
			return null;
		}
		catch( WorkSheetNotFoundException a )
		{
			log.warn( "getWorkSheets() failed: " + a );
			return null;
		}
	}