Spring Web Flow

org.springframework.webflow.action
Class MultiAction

java.lang.Object
  extended by org.springframework.webflow.action.AbstractAction
      extended by org.springframework.webflow.action.MultiAction
All Implemented Interfaces:
org.springframework.beans.factory.InitializingBean, Action
Direct Known Subclasses:
FormAction

public class MultiAction
extends AbstractAction

Action implementation that bundles two or more action execution methods into a single class. Action execution methods defined by subclasses must adhere to the following signature:

     public Event ${method}(RequestContext context) throws Exception;
 
When this action is invoked, by default the id of the calling action state state is treated as the action execution method name. Alternatively, the execution method name may be explicitly specified as a attribute of the calling action state.

For example, the following action state definition:

     <action-state id="search">
         <evaluate expression="searchAction.executeSearch"/>
         <transition on="success" to="results"/>
     </action-state>
 
... when entered, executes the method:
 public Event search(RequestContext context) throws Exception;
 

One use of the MultiAction is to centralize all command logic for a flow in one place. Another use is to centralize form setup and submit logic in one place, or CRUD (create/read/update/delete) operations for a single domain object in one place.

Author:
Keith Donald, Erwin Vervaet
See Also:
MultiAction.MethodResolver, DefaultMultiActionMethodResolver

Nested Class Summary
static interface MultiAction.MethodResolver
          Strategy interface used by the MultiAction to map a request context to the name of an action execution method.
 
Field Summary
 
Fields inherited from class org.springframework.webflow.action.AbstractAction
logger
 
Constructor Summary
protected MultiAction()
          Protected default constructor; not invokable for direct MultiAction instantiation.
  MultiAction(java.lang.Object target)
          Constructs a multi action that invokes methods on the specified target object.
 
Method Summary
protected  Event doExecute(RequestContext context)
          Template hook method subclasses should override to encapsulate their specific action execution logic.
 MultiAction.MethodResolver getMethodResolver()
          Get the strategy used to resolve action execution method names.
 void setMethodResolver(MultiAction.MethodResolver methodResolver)
          Set the strategy used to resolve action execution method names.
protected  void setTarget(java.lang.Object target)
          Sets the target of this multi action's invocations.
 
Methods inherited from class org.springframework.webflow.action.AbstractAction
afterPropertiesSet, doPostExecute, doPreExecute, error, error, execute, getActionNameForLogging, getEventFactorySupport, initAction, no, result, result, result, result, success, success, yes
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

MultiAction

protected MultiAction()
Protected default constructor; not invokable for direct MultiAction instantiation. Intended for use by subclasses.

Sets the target to this multi action instance.

See Also:
setTarget(Object)

MultiAction

public MultiAction(java.lang.Object target)
Constructs a multi action that invokes methods on the specified target object. Note: invokable methods on the target must conform to the multi action method signature:
       public Event ${method}(RequestContext context) throws Exception;
 

Parameters:
target - the target of this multi action's invocations
Method Detail

setTarget

protected final void setTarget(java.lang.Object target)
Sets the target of this multi action's invocations.

Parameters:
target - the target

getMethodResolver

public MultiAction.MethodResolver getMethodResolver()
Get the strategy used to resolve action execution method names.


setMethodResolver

public void setMethodResolver(MultiAction.MethodResolver methodResolver)
Set the strategy used to resolve action execution method names. Allows full control over the method resolution algorithm. Defaults to DefaultMultiActionMethodResolver.


doExecute

protected final Event doExecute(RequestContext context)
                         throws java.lang.Exception
Description copied from class: AbstractAction
Template hook method subclasses should override to encapsulate their specific action execution logic.

Specified by:
doExecute in class AbstractAction
Parameters:
context - the action execution context, for accessing and setting data in "flow scope" or "request scope"
Returns:
the action result event
Throws:
java.lang.Exception - an unrecoverable exception occured, either checked or unchecked

Spring Web Flow