Spring in ACTION 4th Edition notes-eighth chapter advanced Spring mvc-001-Configuration Springflow (Flow-executor, Flow-registry, flowhandlermapping, Flowhandleradapter)

One

1.Wiring a flow Executor

<flow:flow-executor id= "Flowexecutor"/>

Although the flow executor is responsible for creating and executing flows, it 's not responsible for loading flow Definitions. That's responsibility falls to a flow Registry,which you ' ll create next.

2.Configuring a flow registry

A Flow registry ' s job is to load flow definitions and make them available to the flow exec Utor.

(1) wildcard characters <flow:flow-location-pattern>

1 <flow:flow-registry id= "Flowregistry" base-path= "/web-inf/flows" >2     <flow: Flow-location-pattern value= "*-flow.xml"/>3 </flow:flow-registry>

as declared here, the flow registry would look for flow definitions under the /web-inf/flows directory, as specified in the Base-path attribute. Per the <flow:flow-location-pattern> element, any XML file whose name ends With-flow.xml would
be considered a flow definition.

All flows is referred to by their ID s. Using <flow:flow-location-pattern> as you had, the flow ID is the directory
path relative to the base-path-or the Part of the path represented with the double asterisk

Or

1   <!--the registry of executable flow definitions--2   <flow:flow-registry id= "Flowregistry" Base-path= "/web-inf/flows" >3      <flow:flow-location-pattern value= "/**/*-flow.xml"/>  4   </flow:flow-registry>

(2) Clear location <flow:flow-location>

1 <flow:flow-registry id= "Flowregistry" >2     <flow:flow-location path= "/web-inf/flows /springpizza.xml "/>3 </flow:flow-registry>

When configured the "This", the flow ' s ID is derived from the base name of the flow definition file, Springpizza in this case.

or specify an ID

1 <flow:flow-registry id= "Flowregistry" >2     <flow:flow-location id= "pizza" path= "/ Web-inf/flows/springpizza.xml "/>3 </flow:flow-registry>

3.Handling Flow Requests

(1) Assemble the flowhandlermapping and tell Dispatcherservlet to hand flow to it.

Dispatcherservlet typically dispatches requests to controllers. But for flows, you need a flowhandlermapping to the help Dispatcherservlets know that it should send flow requests to Spring Web Flow

1 <!--Maps request paths to flows in the flowregistry-->2   class= " Org.springframework.webflow.mvc.servlet.FlowHandlerMapping ">3     <property name=" Flowregistry " ref= "Flowregistry"/>4   </bean>

as can see, the flowhandlermapping are wired with a reference to the flow registry So it knows when a request ' s URL maps to a flow. For example, if you had a flow whose ID is pizza and then flowhandlermapping would know to map a request to that FL ow if the request ' s URL pattern (relative to the application context path) Is/pizza.

(2) Assembly Flowhandleradapter

whereas the flowhandlermapping ' s job is to direct flow requests to Spring WEB&NBSP;flow, it's the job of a  flowhandleradapter to answer this call. a flowhandleradapter  is equivalent to a Spring MVC controller in that it Handl Es requests coming in for a  flow and processes those requests.

 1  <!--2   Dispatches requests mapped to flows to Flowhandler implementations  3 -->4  <bean class  = " Org.springframework.webflow.mvc.servlet.FlowHandlerAdapter ">5  < Property Name= "Flowexecutor" ref= "Flowexecutor"/>6  </bean> 

This handler adapter is the bridge between Dispatcherservlet and Spring Web Flow. It handles flow requests and manipulates the flow based on those requests. Here, it 's wired with a reference to the flow executor-to- execute the flows for which it handles request S.

Spring in ACTION 4th Edition notes-eighth chapter advanced Spring mvc-001-Configuration Springflow (Flow-executor, Flow-registry, flowhandlermapping, Flowhandleradapter)