public boolean insertBill(Bill b){
		connectionDB();
		boolean isUpdate=false;
		String sql="insert into bill values(bill_seq.nextval,?,?,?,?,?,?,?)";
		try {
			ps=conn.prepareStatement(sql);
//			ps.setLong(1, b.getBillId());
			ps.setString(6, b.getGoodsDescrible());
			ps.setString(1, b.getGoodsName());
			ps.setString(4, b.getIsPay());
			ps.setString(5, b.getSupplierName());
			ps.setDate(7, b.getBillTime());
			ps.setInt(2,b.getGoodsNum());
			ps.setDouble(3, b.getMoney());
			int rows=ps.executeUpdate();
			isUpdate=rows>0?true:false;	
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally{
			closeDB();
			
		}
		return isUpdate;
	}