org.portico.lrc.handlers
Class REQ_SubscribeObjectHandler

java.lang.Object
  com.lbf.commons.messaging.AbstractMessageHandler
      org.portico.lrc.handlers.LRCMessageHandler
          org.portico.lrc.handlers.REQ_SubscribeObjectHandler

All Implemented Interfaces:

com.lbf.commons.messaging.IMessageHandler

public class REQ_SubscribeObjectHandler
extends LRCMessageHandler

This handler manages object attribute subscribe/unsubscribe requests. It will make all the appropriate checks before sending the request on to the RTI, and it will store the relevant information once it has been returned from the RTI.

Before *ANY* request is processed, the processMessage() method will check to make sure the federate is an execution member and that a save or restore is not currently in progress.

Field Summary

Fields inherited from class org.portico.lrc.handlers.LRCMessageHandler

interests, logger, lrc, regions, repository, state

Fields inherited from class com.lbf.commons.messaging.AbstractMessageHandler

augmentable, name

Constructor Summary

REQ_SubscribeObjectHandler()

Method Summary

void	processMessage(com.lbf.commons.messaging.MessageContext context) Processes an incoming message and depending on the type, delegates it to the appropriate private handling method.
private void	subscribe(com.lbf.commons.messaging.MessageContext context) Handle a request to subscribe to a set of attributes for a specific object class.
private void	subscribeWithDDM(com.lbf.commons.messaging.MessageContext context, RTI_SubscribeObjectClass request) This method handles subscription requests that include DDM information.
private void	unsubscribe(com.lbf.commons.messaging.MessageContext context) This method handles requests to remove a subscription for a specific object class (or a subset of attributes within that class).
private void	unsubscribeDDM(com.lbf.commons.messaging.MessageContext context, RTI_UnsubscribeObjectClass request) This method handles an unsubscribe request when DDM information is used.
private void	unsubscribeImplicit(com.lbf.commons.messaging.MessageContext context, int classHandle, String target) This method converts a previous subscription request that contained 0-attributes into an unsubscribe request (RTI_UnsubscribeObjectClass) for the identified class.
private void	unsubscribeImplicitDDM(com.lbf.commons.messaging.MessageContext context, int classHandle, String target, int regionToken) Same as unsubscribeImplicit(MessageContext, int, String) except that it can include region data.
private void	validateDDM(int classHandle, int regionToken, Set<Integer> attributes) This method will validate the DDM related parts of a subscription request.
private void	validateHandles(int classHandle, Set<Integer> attributes) This method will verify that the object class exists in the FOM, and that each of the attribute handles represents an attribute that exists for the object class.
private void	validateRegion(int regionToken) Makes sure the region is valid (that we know about it).
private void	validateSubscribed(int classHandle) Validates that the given object class is subscribed by this federate

Methods inherited from class org.portico.lrc.handlers.LRCMessageHandler

error, error, getConnection, getFOM, initialize, sendMessage, success, success, success

Methods inherited from class com.lbf.commons.messaging.AbstractMessageHandler

getName, isAugmentable, setAugmentable, setName

Methods inherited from class java.lang.Object

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

Constructor Detail

REQ_SubscribeObjectHandler

public REQ_SubscribeObjectHandler()

Method Detail

processMessage

public void processMessage(com.lbf.commons.messaging.MessageContext context)
                    throws Exception

Processes an incoming message and depending on the type, delegates it to the appropriate private handling method.

Specified by:

processMessage in interface com.lbf.commons.messaging.IMessageHandler

Specified by:

processMessage in class LRCMessageHandler

Throws:

Exception

subscribe

private void subscribe(com.lbf.commons.messaging.MessageContext context)
                throws Exception

Handle a request to subscribe to a set of attributes for a specific object class. This method will first validate that each of the attribute handles exists in the FOM and then it will send the request on to the RTI. If the RTI returns a success response, the new subscription interest will be recorded in the LRCInterestManager.

If the provided set of attribute handles is empty, the request is taken to be an implicit unpublication request for all attributes of the object class. In that case, processing is turned over to #unsubscribeOCImplicit(MessageContext, int, String).

Throws:

Exception

subscribeWithDDM

private void subscribeWithDDM(com.lbf.commons.messaging.MessageContext context,
                              RTI_SubscribeObjectClass request)
                       throws Exception

This method handles subscription requests that include DDM information. Although these requests only need to be handled a little bit differently, they do need this handling to occur in a few places. Rather than just littering the original subscription process with a bunch of "if(usesDDM)" blocks, it's probably just cleaner to split this processing off into a separate method.

Throws:

Exception

unsubscribeImplicit

private void unsubscribeImplicit(com.lbf.commons.messaging.MessageContext context,
                                 int classHandle,
                                 String target)
                          throws Exception

This method converts a previous subscription request that contained 0-attributes into an unsubscribe request (RTI_UnsubscribeObjectClass) for the identified class. It then passes this request to the #unsubscribeOC(MessageContext) method for processing.

Throws:

Exception

unsubscribeImplicitDDM

private void unsubscribeImplicitDDM(com.lbf.commons.messaging.MessageContext context,
                                    int classHandle,
                                    String target,
                                    int regionToken)
                             throws Exception

Same as unsubscribeImplicit(MessageContext, int, String) except that it can include region data. If you don't want to include a region, either call the other method or pass PorticoConstants.NULL_HANDLE as the regionToken.

Throws:

Exception

unsubscribe

private void unsubscribe(com.lbf.commons.messaging.MessageContext context)
                  throws Exception

This method handles requests to remove a subscription for a specific object class (or a subset of attributes within that class). The method will first valudate that the object class handle exists in the FOM before confirming that the class is currently subscribed to by the federate. If everything is in order, the request is sent to the RTI where it will be processed. Assuming that the RTI responds with a success message, this method will then remove any subscription interest from the LRCInterestManager

If the unsubscription request includes a specific set of attributes that should be unsubscribed (rather than the entire class), the method will validate that each of the attribute handles exists in the FOM before allowing the message to travel to the RTI.

Throws:

Exception

unsubscribeDDM

private void unsubscribeDDM(com.lbf.commons.messaging.MessageContext context,
                            RTI_UnsubscribeObjectClass request)
                     throws Exception

This method handles an unsubscribe request when DDM information is used. The process varies from the standard unsubscribe in a small ways, but in a number of places. Rather than litter the standard unsubscribe handler with "if(usesDDM)" statements, it is cleaner to just factor this process out into a separate method.

Throws:

Exception

validateHandles

private void validateHandles(int classHandle,
                             Set<Integer> attributes)
                      throws JObjectClassNotDefined,
                             JAttributeNotDefined,
                             JRTIinternalError

This method will verify that the object class exists in the FOM, and that each of the attribute handles represents an attribute that exists for the object class.

Throws:

JObjectClassNotDefined - If the classHandle doesn't represent a class in the FOM

JAttributeNotDefined - If an attribute handle doesn't represent an attribute in the defined object class

JRTIinternalError - If there is a problem locating the FOM

validateSubscribed

private void validateSubscribed(int classHandle)
                         throws JObjectClassNotSubscribed

Validates that the given object class is subscribed by this federate

Throws:

JObjectClassNotSubscribed - If the object class is not currently subscribed to

validateDDM

private void validateDDM(int classHandle,
                         int regionToken,
                         Set<Integer> attributes)
                  throws JRegionNotKnown,
                         JInvalidRegionContext,
                         JRTIinternalError

This method will validate the DDM related parts of a subscription request. It will make sure that the federate knows about the region provided with the request and that the region is valid for all the identified attributes in the request (i.e. that the FOM specifies the appropriate space).

Throws:

JRegionNotKnown

JInvalidRegionContext

JRTIinternalError

validateRegion

private void validateRegion(int regionToken)
                     throws JRegionNotKnown

Makes sure the region is valid (that we know about it). If it isn't, throws an exception

Throws:

JRegionNotKnown