Shulou(Shulou.com)06/03 Report--

In the actual development, I encountered a common piece of code, several methods need to be dropped, but if you pull it out to write a method, the input parameters are different, so I thought of using generics.

For example, this is a common code:

/ / to save order information, multiple method calls are required: OrderFilterRequest orderFilterRequest = new OrderFilterRequest (); btOrderFilterRequest.setUserId ("1"); btOrderFilterRequest.setStatus ("0"); List orderResultList = orderService.findOrders (orderFilterRequest); Order result = null; if (CollectionUtils.isEmpty (orderResultList)) {Order order = CopierUtils.convert (request, Order.class); order.setRealName (customer.getRealName ()); order.setIdcardNo (customer.getIdcardNo ()); order.setOrderNo ("order" + DateUtil.getYMDHMS ()) Order.setStatus ("0"); order.setCreateTime (new Date ()); order.setUpdateTime (new Date ()); order.setUserId ("1"); result = orderService.createOrder (Order);} else {Order orderResult = orderResultList.get (0); CopierUtils.copy (request, orderResult); orderResult.setUpdateTime (new Date ()); result = orderService.updateOrder (btOrderResult);}

Refine this code into a generic class:

@ Transactional (readOnly = true) @ Componentpublic class OrderRequest {@ Autowired private OrderService orderService; @ Transactional public Order orderInfoSave (T request) {OrderFilterRequest orderFilterRequest = new OrderFilterRequest (); btOrderFilterRequest.setUserId ("1"); btOrderFilterRequest.setStatus ("0"); List orderResultList = orderService.findOrders (orderFilterRequest); Order result = null If (CollectionUtils.isEmpty (orderResultList)) {Order order = CopierUtils.convert (request, Order.class); order.setRealName (customer.getRealName ()); order.setIdcardNo (customer.getIdcardNo ()); order.setOrderNo ("order" + DateUtil.getYMDHMS ()); order.setStatus ("0") Order.setCreateTime (new Date ()); order.setUpdateTime (new Date ()); order.setUserId ("1"); result = orderService.createOrder (Order);} else {Order orderResult = orderResultList.get (0); CopierUtils.copy (request, orderResult) OrderResult.setUpdateTime (new Date ()); result = orderService.updateOrder (btOrderResult);} return result;}}

Here's how I called it at first:

Public void method1 (Request1 request) {OrderRequest orderCreateRequest = new OrderRequest (); Order result = OrderCreateRequest.orderInfoSave (request);} public void method2 (Request2 request) {OrderRequest orderCreateRequest = new OrderRequest (); Order result = OrderCreateRequest.orderInfoSave (request);}

But orderService in OrderRequest is null. (injecting service interface into controller layer, injecting orderService into service layer is valuable), try many solutions, and finally find that the original spring custom class instantiation also needs to be instantiated by injection, not new, otherwise it is out of the management of spring. Just change it to the following way:

@ Autowiredprivate OrderRequest request1;@Autowiredprivate OrderRequest request2;public void method1 (Request1 request) {Order result = request1.orderInfoSave (request);} public void method2 (Request2 request) {Order result = request2.orderInfoSave (request);}

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