org.apache.struts2.dispatcher.mapper
Class CompositeActionMapper

java.lang.Object
  org.apache.struts2.dispatcher.mapper.CompositeActionMapper

All Implemented Interfaces:

ActionMapper

public class CompositeActionMapper
extends Object
implements ActionMapper

A composite action mapper that is capable of delegating to a series of ActionMapper if the former failed to obtained a valid ActionMapping or uri.

It is configured through struts.properties.

For example, with the following entries in struts.properties

 <bean type="org.apache.struts2.dispatcher.mapper.ActionMapper" name="struts" 
       class="org.apache.struts2.dispatcher.mapper.CompositeActionMapper" />
 <constant name="struts.mapper.composite" 
       value="org.apache.struts2.dispatcher.mapper.DefaultActionMapper,org.apache.struts2.dispatcher.mapper.RestfulActionMapperorg.apache.struts2.dispatcher.mapper.Restful2ActionMapper" />
 

When getMapping(HttpServletRequest, ConfigurationManager) or getUriFromActionMapping(ActionMapping) is invoked, CompositeActionMapper would go through these ActionMappers in sequence starting from ActionMapper identified by 'struts.mapper.composite.1', followed by 'struts.mapper.composite.2' and finally 'struts.mapper.composite.3' (in this case) until either one of the ActionMapper return a valid result (not null) or it runs out of ActionMapper in which case it will just return null for both getMapping(HttpServletRequest, ConfigurationManager) and getUriFromActionMapping(ActionMapping) methods.

For example with the following in struts-*.xml :-

    <bean type="org.apache.struts2.dispatcher.mapper.ActionMapper" name="struts" 
       class="org.apache.struts2.dispatcher.mapper.CompositeActionMapper" />
    <constant name="struts.mapper.composite" 
       value="org.apache.struts2.dispatcher.mapper.DefaultActionMapper,foo.bar.MyActionMapper,foo.bar.MyAnotherActionMapper" />
 

CompositeActionMapper will be configured with 3 ActionMapper, namely "DefaultActionMapper", "MyActionMapper" and "MyAnotherActionMapper". CompositeActionMapper would consult each of them in order described above.

Version:

$Date: 2008-04-27 08:41:38 -0500 (Sun, 27 Apr 2008) $ $Id: CompositeActionMapper.java 651946 2008-04-27 13:41:38Z apetrelli $

See Also:

ActionMapper, ActionMapping

Field Summary

protected List<ActionMapper>	actionMappers
protected Container	container
private static Logger	LOG

Constructor Summary

CompositeActionMapper()

Method Summary

ActionMapping	getMapping(HttpServletRequest request, ConfigurationManager configManager) Expose the ActionMapping for the current request
ActionMapping	getMappingFromActionName(String actionName) Expose the ActionMapping for the specified action name
String	getUriFromActionMapping(ActionMapping mapping) Convert an ActionMapping into a URI string
void	setActionMappers(String list)
void	setContainer(Container container)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

LOG

private static final Logger LOG

container

protected Container container

actionMappers

protected List<ActionMapper> actionMappers

Constructor Detail

CompositeActionMapper

public CompositeActionMapper()

Method Detail

setContainer

public void setContainer(Container container)

setActionMappers

public void setActionMappers(String list)

getMapping

public ActionMapping getMapping(HttpServletRequest request,
                                ConfigurationManager configManager)

Description copied from interface: ActionMapper

Expose the ActionMapping for the current request

Specified by:

getMapping in interface ActionMapper

Parameters:

request - The servlet request

configManager - The current configuration manager

Returns:

The appropriate action mapping

getMappingFromActionName

public ActionMapping getMappingFromActionName(String actionName)

Description copied from interface: ActionMapper

Expose the ActionMapping for the specified action name

Specified by:

getMappingFromActionName in interface ActionMapper

Parameters:

actionName - The name of the action that may have other information embedded in it

Returns:

The appropriate action mapping

getUriFromActionMapping

public String getUriFromActionMapping(ActionMapping mapping)

Description copied from interface: ActionMapper

Convert an ActionMapping into a URI string

Specified by:

getUriFromActionMapping in interface ActionMapper

Parameters:

mapping - The action mapping

Returns:

The URI string that represents this mapping