接口 WebRequestInterceptor
- 所有已知子接口:
AsyncWebRequestInterceptor
public interface WebRequestInterceptor
Interface for general web request interception. Allows for being applied to Servlet request by building on theWebRequest
abstraction.This interface assumes MVC-style request processing: A handler gets executed, exposes a set of model objects, then a view gets rendered based on that model. Alternatively, a handler may also process the request completely, with no view to be rendered.
In an async processing scenario, the handler may be executed in a separate thread while the main thread exits without rendering or invoking the
postHandle
andafterCompletion
callbacks. When concurrent handler execution completes, the request is dispatched back in order to proceed with rendering the model and all methods of this contract are invoked again. For further options and comments seeorg.springframework.web.context.request.async.AsyncWebRequestInterceptor
This interface is deliberately minimalistic to keep the dependencies of generic request interceptors as minimal as feasible.
- 从以下版本开始:
- 2.0
- 作者:
- Juergen Hoeller
- 另请参阅:
ServletWebRequest
,DispatcherServlet
,AbstractHandlerMapping.setInterceptors(java.lang.Object...)
,HandlerInterceptor
方法概要
所有方法 实例方法 抽象方法 修饰符和类型 方法 说明 void
afterCompletion(WebRequest request, Exception ex)
Callback after completion of request processing, that is, after rendering the view.void
postHandle(WebRequest request, ModelMap model)
Intercept the execution of a request handler after its successful invocation, right before view rendering (if any).void
preHandle(WebRequest request)
Intercept the execution of a request handler before its invocation.
方法详细资料
preHandle
void preHandle(WebRequest request) throws Exception
Intercept the execution of a request handler before its invocation.Allows for preparing context resources (such as a Hibernate Session) and expose them as request attributes or as thread-local objects.
- 参数:
request
- the current web request- 抛出:
Exception
- in case of errors
postHandle
void postHandle(WebRequest request, @Nullable ModelMap model) throws Exception
Intercept the execution of a request handler after its successful invocation, right before view rendering (if any).Allows for modifying context resources after successful handler execution (for example, flushing a Hibernate Session).
- 参数:
request
- the current web requestmodel
- the map of model objects that will be exposed to the view (may benull
). Can be used to analyze the exposed model and/or to add further model attributes, if desired.- 抛出:
Exception
- in case of errors
afterCompletion
void afterCompletion(WebRequest request, @Nullable Exception ex) throws Exception
Callback after completion of request processing, that is, after rendering the view. Will be called on any outcome of handler execution, thus allows for proper resource cleanup.Note: Will only be called if this interceptor's
preHandle
method has successfully completed!- 参数:
request
- the current web requestex
- exception thrown on handler execution, if any- 抛出:
Exception
- in case of errors