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Spring StateMachine How do I know if a transistion is rejected due to failed guard or action?

I have the same question as in the topic below, but I'm not so sure if my approach is wrong.
How do I know if a guard rejected a transistion
My app is a linear step-by-step strategy board game with several different game settings. I've decided to use Spring StateMachine to solve as in my opinion (and so far) it solves a lot little code-related organisational problems But now I'm stacked
The problem I have run into is that I can't say if my event passed all the guards and transition occurs. I just get true-flag when an event is added to the queue
The approach I'm following is passing data via event-context, validation of one with guards and apply changes using actions
transitions
.withExternal().source(SPEECHES).target(VOTING).event(VOTING_EVENT)
.guard(Guard.and(
guards.get(NoVotesFromSuspectedGuard.QUALIFIER),
guards.get(NoSelfVotingGuard.QUALIFIER),
guards.get(NoDeadParticipantsVotingGuard.QUALIFIER),
guards.get(NoVotingForDeadParticipantsGuard.QUALIFIER),
votingOutOfParticipantListGuardFactory.get(NUMBER_OF_PLAYERS),
guards.get(VotingBasedOnPreviousOneGuard.QUALIFIER)
))
.action(actions.get(CalculateVotingAction.QUALIFIER))
As I understand now, there is no possibility to notify event-supplier about failed guard evaluation. If so, just let me know and I will switch to another SM implementation. But if there is any possibility of solving my problem, please help me.
The behaviour I expect is any meta info of failed guard (to build formatted error message)

You can use some context flag, for example context.put("NoVotesFromSuspectedGuard", false) when "NoVotesFromSuspectedGuard" isn't success and then you can check this variable in your invoke code context.getExternalVariables().get("NoVotesFromSuspectedGuard", Boolean.class).
Also, in Spring State Machine you can declare ActionListener bean, which contains some different methods for StateMachine events monitoring.
For more information, you can see Habr(Russian)

Spring Cloud Function / propagates request to Function

I'm new to Java and to Spring, and I'm not sure how this example code is working in that "SpringBootRequestHandler" implements the AWS RequestHandler, and also "propagates the request to our function".
The example is found here: https://dzone.com/articles/run-code-with-spring-cloud-function-on-aws-lambda
I've reviewed this code for awhile - and I'm not connecting the dots on how the UppercaseFunction gets invoked via the UppercaseFunctionHandler.
I'll apologize in advance if this isn't the right place to ask this question, but I'm not sure where else I can ask for help!

So UppercaseFunctionHandler extends SpringBootRequestHandler which extends SpringFunctionInitializer which is where the magic happens.
When a request is received, the handler will attempt to initialize the spring context.
During initialization, it will look up the property function.name defined in the application.properties which is the name of function component bean that would of been discovered during component scanning.
So in summary there is a lot of indirection going on here, and it's certainly hard to understand without digging into the framework code and having a bit of knowledge about the way spring works.

Can a java listener catch an event triggered from within itself?

I need some help understanding a piece of code found in an application developed by my company. Because it is proprietary code I am not able to post the exact snippet but I will try to explain my problem.
The application is a java ee webapp, that has a listener implemented to catch a certain type of event. All normal so far...
Here's where it gets weird. The listener, after it catches the event it's looking for, triggers the same type of event from within itself, before finishing the rest of it's instructions.
It seems to be like calling a method from withing itself, only in this case it's a listener triggering the same event it is listening for.
It doesn't work, in this specific implementation, and that's a problem.
My question is: could this actually work?
I've tried to explain as best as I could but this is a strange piece of code. I tried to make a diagram of the way it is trying to work, maybe that will be more clear than my explanation. Image link below:
Please help me understand if what this person was trying to do is actually achievable or just very bad design.
Thanks in advance!

Sounds strange. It is normal for one event listener to "respond" by sending a separate event with the result - events are one way. Look carefully at the event identification, character for character, to ensure it really does send the same event it receives. Also, trying scrubbing out any company details and provide the code.

Java remote interface blocks the use of my GUI

I've given a bank application which I should modify so the balance of an account gets updated on every GUI screen. This should be done with RMI(Observable) in my example. I already made this work, at least, I'm almost certain about that.
There is a REMOTE interface called IBankingSession.
This REMOTE interface should have a method like setGUI(BankSessionController) or something like this. But, This isn't possible because the JavaFX parts aren't Serializable. The IBankingSession doesn't have any relationship to a GUI.
How can I link an instance of IBankingSession to this GUI? So I can update the GUI from this instance? It also feels weird to make a method like setGUI in a REMOTE interface. Because the GUI is of course, on the same screen as where the session is created.
I'm curious for some good idea's. Thanks in advance.
IBankingSession session = desk.logIn(tfAccount.getText(), tfPassword.getText());

First of all: you don't want to link your "remote" thing directly to your local clients that make use of it. That IBankingSession has no business knowing anything about the fact that your client wants to use JavaFx to put something on the user screens.
Instead, try something like this: define an interface that allows for callbacks (in other words: some kind of "push" model):
A client registers with the remote server; telling it: "I am interested in balance updates".
Then, upon a "balance" update, the remote service pushes that information to each client.
Now each client will be notified; and can then decide what to do with incoming updates; for example update some JavaFx UI component; or maybe, to log them into some persistent storage - giving you one mechanism that might be useful for a huge variety of different use cases.

You shouldn't be using observables at all, and certainly not over a network.
As far as RMI goes, you should strenously avoid anything in the nature of a client-side callback. There are firewall problems, latency problems, connectivity problems, ... every kind of thing that could cause your client to misfire.
You need to completely rethink this. It is not a viable design.

How to send a message using Apache Camel?

I am trying to create a sample application hosted at "mina:tcp://localhost:9991" that sends a very simple message to a server hosted at "mina:tcp://localhost:9990".
Now admittedly I have some problems understanding how to do this. My first approach was to create a class called Message, that has two fields: String order and String host. However, I am terribly confused on how to do this.
First I tried to follow the loadbalancer-example basing myself on the ReportGenerator and create a MessageGenerator class that could create a message and return it:
http://camel.apache.org/loadbalancing-mina-example.html
However, there is a problem, I need parameters to create my Message, something that doesn't happen when creating the Report from the example:
//Message constructor
public Message(String order, String host){
//constructor stuff
}
By reading Camel in Action I know how to use beans to call methods that have no parameters, however I still do not understand how I should use them to call a method that has several parameters (Am I forced to use processors?)
Then i realized that perhaps I am complicating things a little bit and there is an easier way to send messages. So I tried another approach that resulted in a small sample of code that does not work as well. I have created a separate question for that matter:
Apache camel send a simple message
Obviously I am doing something wrong and I don't get what. So, I have 2 questions:
Manning's Camel in Action defines an Easy way and a Hard way to use beans, but I did not understand the easy way of using beans with parameters. Can someone provide an example of it?
Is there a way to send a message composed of several fields in Camel (an easy way, without processors) that does not involve using beans? If so, how?

There are several ways to sends Messages in Camel. According to the help provided in the Camel forums, the two best are:
Using beans linked to POJOS and routes (example: http://camel.apache.org/loadbalancing-mina-example.html)
Using the Producer Template (docs: http://camel.apache.org/producertemplate.html)
Hope it helps someone one day.