public Object[][] checkOverdue() {
		Statement stmt;
		ResultSet rs = null;
		Object[][] overdueList = null;
		int bid;
		int borid;
		int callNo;
		int copyNo;
		Date outDate;
		String title = null;
		int count = 0;
		Borrowing bor = new Borrowing();
		Book book = new Book();
		
		try{
			stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
			rs = stmt.executeQuery("SELECT * FROM borrowing WHERE borrowing_inDate IS NULL");
			
			try {
			  rs.last();
			   count = rs.getRow();
			    rs.beforeFirst();
			}
			catch(Exception ex) {
				return null;
			} 
			if(count > 0){
			overdueList = new Object[count][5];
			}
			
			while(rs.next()){
				bid = rs.getInt("borr_bid");
				borid = rs.getInt("borrowing_borid");
				callNo = rs.getInt("book_callNo");
				copyNo = rs.getInt("bookcopy_copyNo");
				outDate = rs.getDate("borrowing_outDate");
				title = book.getTitle(callNo);

				if(bor.isOverdue(borid)){
					overdueList[overdueListCount][0] = bid;
					overdueList[overdueListCount][1] = callNo;
					overdueList[overdueListCount][2] = copyNo;	
					overdueList[overdueListCount][3] = title;
					overdueList[overdueListCount][4] = outDate;
					overdueListCount++;				

				}				
			}
			stmt.close();
			return overdueList;		
		}
		catch(SQLException e){
			System.out.println("Message: " + e.getMessage());
		}
		
		
		return null;
		
	}
	

	
	//checks array (testing method)
//	public void printArray(){
//
//		System.out.println("checkoutcount in printarray is " + checkOutCount);
//		for(int k = 0; k < checkOutCount; k++){
//			for(int j = 0; j < 5 ; j++){
//				
//				System.out.println(receipt[k][j] + " ");
//
//			}
//			System.out.println(" ");
//		}
//	}