org.springframework.web.portlet.handler
Class PortletModeParameterHandlerMapping

java.lang.Object
  extended by org.springframework.context.support.ApplicationObjectSupport
      extended by org.springframework.web.portlet.handler.AbstractHandlerMapping
          extended by org.springframework.web.portlet.handler.AbstractMapBasedHandlerMapping<org.springframework.web.portlet.handler.PortletModeParameterLookupKey>
              extended by org.springframework.web.portlet.handler.PortletModeParameterHandlerMapping
All Implemented Interfaces:
Aware, ApplicationContextAware, Ordered, HandlerMapping

public class PortletModeParameterHandlerMapping
extends AbstractMapBasedHandlerMapping<org.springframework.web.portlet.handler.PortletModeParameterLookupKey>

Implementation of the HandlerMapping interface to map from the current PortletMode and a request parameter to request handler beans. The mapping consists of two levels: first the PortletMode and then the parameter value. In order to be mapped, both elements must match the mapping definition.

This is a combination of the methods used in PortletModeHandlerMapping and ParameterHandlerMapping. Unlike those two classes, this mapping cannot be initialized with properties since it requires a two-level map.

The default name of the parameter is "action", but can be changed using setParameterName().

By default, the same parameter value may not be used in two different portlet modes. This is so that if the portal itself changes the portlet mode, the request will no longer be valid in the mapping. This behavior can be changed with setAllowDupParameters().

The bean configuration for this mapping will look somthing like this:

 <bean id="portletModeParameterHandlerMapping" class="org.springframework.web.portlet.handler.PortletModeParameterHandlerMapping">
   <property name="portletModeParameterMap">
     <map>
       <entry key="view"> <!-- portlet mode: view -->
         <map>
           <entry key="add"><ref bean="addItemHandler"/></entry>
           <entry key="edit"><ref bean="editItemHandler"/></entry>
           <entry key="delete"><ref bean="deleteItemHandler"/></entry>
         </map>
       </entry>
       <entry key="edit"> <!-- portlet mode: edit -->
         <map>
           <entry key="prefs"><ref bean="preferencesHandler"/></entry>
           <entry key="resetPrefs"><ref bean="resetPreferencesHandler"/></entry>
         </map>
       </entry>
     </map>
   </property>
 </bean>

This mapping can be chained ahead of a PortletModeHandlerMapping, which can then provide defaults for each mode and an overall default as well.

Thanks to Rainer Schmitz and Yujin Kim for suggesting this mapping strategy!

Since:
2.0
Author:
John A. Lewis, Juergen Hoeller
See Also:
ParameterMappingInterceptor

Nested Class Summary
 
Nested classes/interfaces inherited from class org.springframework.web.portlet.handler.AbstractMapBasedHandlerMapping
AbstractMapBasedHandlerMapping.PortletRequestMappingPredicate
 
Field Summary
static String DEFAULT_PARAMETER_NAME
          Default request parameter name to use for mapping to handlers: "action".
 
Fields inherited from class org.springframework.context.support.ApplicationObjectSupport
logger
 
Fields inherited from interface org.springframework.core.Ordered
HIGHEST_PRECEDENCE, LOWEST_PRECEDENCE
 
Constructor Summary
PortletModeParameterHandlerMapping()
           
 
Method Summary
protected  org.springframework.web.portlet.handler.PortletModeParameterLookupKey getLookupKey(javax.portlet.PortletRequest request)
          Returns a lookup key that combines the current PortletMode and the current value of the specified parameter.
 void initApplicationContext()
          Calls the registerHandlers method in addition to the superclass's initialization.
protected  void registerHandler(javax.portlet.PortletMode mode, Map<String,?> parameterMap)
          Register all handlers specified in the given parameter map.
protected  void registerHandler(javax.portlet.PortletMode mode, String parameter, Object handler)
          Register the given handler instance for the given PortletMode and parameter value, under an appropriate lookup key.
protected  void registerHandlersByModeAndParameter(Map<String,Map<String,?>> portletModeParameterMap)
          Register all handlers specified in the Portlet mode map for the corresponding modes.
 void setAllowDuplicateParameters(boolean allowDuplicateParameters)
          Set whether to allow duplicate parameter values across different portlet modes.
 void setParameterName(String parameterName)
          Set the name of the parameter used for mapping to handlers.
 void setPortletModeParameterMap(Map<String,Map<String,?>> portletModeParameterMap)
          Set a Map with portlet mode names as keys and another Map as values.
 
Methods inherited from class org.springframework.web.portlet.handler.AbstractMapBasedHandlerMapping
getHandlerInternal, registerHandler, registerHandler, registerHandlers, setLazyInitHandlers
 
Methods inherited from class org.springframework.web.portlet.handler.AbstractHandlerMapping
adaptInterceptor, extendInterceptors, getAdaptedInterceptors, getDefaultHandler, getHandler, getHandlerExecutionChain, getOrder, initInterceptors, setApplyWebRequestInterceptorsToRenderPhaseOnly, setDefaultHandler, setInterceptors, setOrder
 
Methods inherited from class org.springframework.context.support.ApplicationObjectSupport
getApplicationContext, getMessageSourceAccessor, initApplicationContext, isContextRequired, requiredContextClass, setApplicationContext
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

DEFAULT_PARAMETER_NAME

public static final String DEFAULT_PARAMETER_NAME
Default request parameter name to use for mapping to handlers: "action".

See Also:
Constant Field Values
Constructor Detail

PortletModeParameterHandlerMapping

public PortletModeParameterHandlerMapping()
Method Detail

setParameterName

public void setParameterName(String parameterName)
Set the name of the parameter used for mapping to handlers.

Default is "action".


setPortletModeParameterMap

public void setPortletModeParameterMap(Map<String,Map<String,?>> portletModeParameterMap)
Set a Map with portlet mode names as keys and another Map as values. The sub-map has parameter names as keys and handler bean or bean names as values.

Convenient for population with bean references.

Parameters:
portletModeParameterMap - two-level map of portlet modes and parameters to handler beans

setAllowDuplicateParameters

public void setAllowDuplicateParameters(boolean allowDuplicateParameters)
Set whether to allow duplicate parameter values across different portlet modes. Default is "false".

Doing this is dangerous because the portlet mode can be changed by the portal itself and the only way to see that is a rerender of the portlet. If the same parameter value is legal in multiple modes, then a change in mode could result in a matched mapping that is not intended and the user could end up in a strange place in the application.


initApplicationContext

public void initApplicationContext()
                            throws BeansException
Calls the registerHandlers method in addition to the superclass's initialization.

Overrides:
initApplicationContext in class AbstractHandlerMapping
Throws:
ApplicationContextException - in case of initialization errors
BeansException - if thrown by ApplicationContext methods
See Also:
AbstractMapBasedHandlerMapping.registerHandlers(java.util.Map)

registerHandlersByModeAndParameter

protected void registerHandlersByModeAndParameter(Map<String,Map<String,?>> portletModeParameterMap)
Register all handlers specified in the Portlet mode map for the corresponding modes.

Parameters:
portletModeParameterMap - Map with mode names as keys and parameter Maps as values

registerHandler

protected void registerHandler(javax.portlet.PortletMode mode,
                               Map<String,?> parameterMap)
Register all handlers specified in the given parameter map.

Parameters:
parameterMap - Map with parameter names as keys and handler beans or bean names as values

registerHandler

protected void registerHandler(javax.portlet.PortletMode mode,
                               String parameter,
                               Object handler)
                        throws BeansException,
                               IllegalStateException
Register the given handler instance for the given PortletMode and parameter value, under an appropriate lookup key.

Parameters:
mode - the PortletMode for which this mapping is valid
parameter - the parameter value to which this handler is mapped
handler - the handler instance bean
Throws:
BeansException - if the handler couldn't be registered
IllegalStateException - if there is a conflicting handler registered
See Also:
AbstractMapBasedHandlerMapping.registerHandler(Object, Object)

getLookupKey

protected org.springframework.web.portlet.handler.PortletModeParameterLookupKey getLookupKey(javax.portlet.PortletRequest request)
                                                                                      throws Exception
Returns a lookup key that combines the current PortletMode and the current value of the specified parameter.

Specified by:
getLookupKey in class AbstractMapBasedHandlerMapping<org.springframework.web.portlet.handler.PortletModeParameterLookupKey>
Parameters:
request - current portlet request
Returns:
the lookup key (never null)
Throws:
Exception - if key computation failed
See Also:
PortletRequest.getPortletMode(), setParameterName(java.lang.String)