Changes to Event Scheduling since version 20.0

[pv2-0]

Hi,

I am getting the error below about a null pointer error. I think I have narrowed down that it happens in my vehicle application. I printed messages to the log at various points and it makes it to the end of my onVehicleUpdated() function, doesn't enter any other function after, and stops. From reading the documentation, I believe it is an issue with event scheduling at the end of the onVehicleUpdated function. In the Tiergarten tutorial, there are new events created at the end of onVehicleUpdated(). In other examples, this isn't done. My program worked in version 20.0 and I am now trying to get it to run in 23.0-SNAPSHOT. Should I be figuring out how to create a new event or send a time advance request at the end of this function? I don't have anything in the processEvent() function, so I don't think I should be doing this but am out of ideas for how to fix this error.

When I map my vehicles to the EventProcessingApp and EventSendingApp, it works, but this might also be because these apps are not receiving inter-vehicle messages?

Thanks

2023-03-22 02:20:33,427 INFO SequentialTimeManagement - Simulation ended after 6s of 1000s (0%) 2023-03-22 02:20:33,428 INFO SequentialTimeManagement - Started: 2023-03-22 02:20:26 2023-03-22 02:20:33,428 INFO SequentialTimeManagement - Ended: 2023-03-22 02:20:33 2023-03-22 02:20:33,430 INFO SequentialTimeManagement - Duration: 00h 00m 06.740s (RTF: 0.00) 2023-03-22 02:20:33,433 INFO SequentialTimeManagement - 2023-03-22 02:20:33,433 INFO SequentialTimeManagement - Simulation interrupted: -1 2023-03-22 02:20:33,647 ERROR MosaicStarter - Stopping simulation due to a critical error. java.lang.NullPointerException: null at org.eclipse.mosaic.fed.sumo.ambassador.AbstractSumoAmbassador.receiveInteraction(AbstractSumoAmbassador.java:1025) at org.eclipse.mosaic.fed.sumo.ambassador.AbstractSumoAmbassador.processInteractionAdvanced(AbstractSumoAmbassador.java:508) at org.eclipse.mosaic.fed.sumo.ambassador.SumoAmbassador.processInteractionAdvanced(SumoAmbassador.java:134) at org.eclipse.mosaic.fed.sumo.ambassador.AbstractSumoAmbassador.processTimeAdvanceGrant(AbstractSumoAmbassador.java:1197) at org.eclipse.mosaic.rti.api.AbstractFederateAmbassador.advanceTime(AbstractFederateAmbassador.java:110) at org.eclipse.mosaic.rti.time.SequentialTimeManagement.runSimulation(SequentialTimeManagement.java:91) at org.eclipse.mosaic.starter.MosaicSimulation.runSimulation(MosaicSimulation.java:193) at org.eclipse.mosaic.starter.MosaicStarter.execute(MosaicStarter.java:132) at org.eclipse.mosaic.starter.MosaicStarter.main(MosaicStarter.java:74)

[schwepmo]

From your posted stack trace it seems like the issue originates from the AbstractSumoAmbassador. And from the corresponding line numbers it seems as if there is some issue with the sensor activation.
If I recall right, you were trying to use the vehicles front/back sensors. Have you added the respective subscriptions to your sumo_config.json:

{
    "sumoConfigurationFile": "<your-sumo-config>",
    "updateInterval": "1s",
    "subscriptions": ["roadposition", "leader"]
}

Edit: If that solves the issue could you let me know how your sumo_config.json looked beforehand? It seems like we're missing a null-check.

[pv2-0]

My sumo_config.json file looked like this before:

{
"sumoConfigurationFile": "scenarioname.sumocfg",
"updateInterval": "1000"
}

I made the suggested changes and now it times out like this:

[pv2-0]

I removed the "leader" subscription and it ran for longer.

At 36 seconds I get this error now:

2023-03-22 16:44:21,991 INFO SequentialTimeManagement - Simulation ended after 36s of 1000s (3%) 2023-03-22 16:44:21,991 INFO SequentialTimeManagement - Started: 2023-03-22 16:44:02 2023-03-22 16:44:21,991 INFO SequentialTimeManagement - Ended: 2023-03-22 16:44:21 2023-03-22 16:44:21,994 INFO SequentialTimeManagement - Duration: 00h 00m 19.387s (RTF: 1.00) 2023-03-22 16:44:21,994 INFO SequentialTimeManagement - 2023-03-22 16:44:21,994 INFO SequentialTimeManagement - Simulation interrupted: -1 2023-03-22 16:44:22,202 ERROR MosaicStarter - Stopping simulation due to a critical error. java.lang.RuntimeException: Scheduled event lies in the past. at org.eclipse.mosaic.lib.util.scheduling.DefaultEventScheduler.scheduleEvents(DefaultEventScheduler.java:82) at org.eclipse.mosaic.fed.sumo.ambassador.AbstractSumoAmbassador.processTimeAdvanceGrant(AbstractSumoAmbassador.java:1212) at org.eclipse.mosaic.rti.api.AbstractFederateAmbassador.advanceTime(AbstractFederateAmbassador.java:110) at org.eclipse.mosaic.rti.time.SequentialTimeManagement.runSimulation(SequentialTimeManagement.java:91) at org.eclipse.mosaic.starter.MosaicSimulation.runSimulation(MosaicSimulation.java:193)

[schwepmo]

If you actually want to get information about leading vehicles though, you'll have to have the leader subscription inserted. Have you had a look in the log files created by MOSAIC, especially, MOSAIC.log, Traffic.log and Application.log? This might help you to further pinpoint the issue.

[pv2-0]

When I add the leader subscription back in and I get the same error as in my first reply, the error is in my Traffic.log, which says:
2023-09-12 18:10:04,110 ERROR SumoAmbassador - Process sumo: Error: Answered with error to command 0xa4: Get Vehicle Variable: unsupported variable 0x78 specified 2023-09-12 18:10:04,113 ERROR SumoAmbassador - Process sumo: Error: Answered with error to command 0xa4: Get Vehicle Variable: unsupported variable 0x0b specified 2023-09-12 18:10:04,113 ERROR SumoAmbassador - Process sumo: Error: Answered with error to command 0xd4: Could not add subscription. Get Vehicle Variable: unsupported variable 0x78 specifiedGet Vehicle Variable: unsupported variable 0x0b specified 2023-09-12 18:10:04,113 ERROR SumoAmbassador - Process sumo: Error: Answered with error to command 0xd4: Wrong position in requestMessage after dispatching command 212. Expected command length was 61 but 52 Bytes were read. 2023-09-12 18:10:33,412 INFO SumoAmbassador - Closing SUMO connection 2023-09-12 18:10:42,156 INFO SumoAmbassador - Process sumo: Step #5.00Interrupt signal received, trying to exit gracefully

From what I understand this indicates an incorrect variable name in my vehicle applications, right? How would I read this error message to figure out the locations of the variables I need to update?

[kschrab]

Which SUMO version are you using? It looks like you are working with a rather old version of SUMO.

I could indeed reproduce your error with SUMO 1.4.0. With SUMO 1.9.2 the execution was successful. Anyways, we recommend to use the latest version 1.18.0!