public List<Supplier> selectSupplier(){
		connectionDB();
		List <Supplier> suppliers=new ArrayList<Supplier>();
		String sql="select supplierId,supplierName,supplierDescrible,linkman,telphone,address from supplier";
		try {
			ps=conn.prepareStatement(sql);
			rs=ps.executeQuery();
			Supplier supplier=null;
			while ( rs.next() ){
				supplier = new Supplier();
				supplier.setSupplierId(rs.getLong("supplierId"));
				supplier.setSupplierName(rs.getString("supplierName"));
				supplier.setSupplierDescrible(rs.getString("supplierDescrible"));
				supplier.setLinkMan(rs.getString("linkMan"));
				supplier.setTelphone(rs.getString("telphone"));
				supplier.setAddress(rs.getString("address"));
				suppliers.add(supplier);
				
			}
			} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally{
			closeDB();
		}
		
		return suppliers;
		
	}