start-state

[ricardomarques]

Hi guys, i'm having a problem with start-states, i had looked at the docs but still i'm a bit confused.

I tried to run this process, and i got nothing on user task list. when I removed the start-state (because I had read somewhere that wasn't mandatory), and still i hadn't nothing on the tasklist.

Is start-state mandatory?

Then I tried to keep start-state but with a task, and then it appears, but the user must set it as done, not quite the behavior that I was expecting.

For my purpuse, state-state would be just a model representation, the first task on my user task list should be "inserir destinatario".

But on jbpm examples, there's examples where exist start-states without task.

I just wanna define a representative start state, where I don't put any action, and he just transitate to the next one.

My process definition:

...
 <swimlane name="default">
 <assignment expression="user(grover)"></assignment>
...
 <task-node name="decidir o destinatario">
 <task name="inserir destinatario" swimlane="default">
 <controller>
 <variable name="destinatario" access="read,write,required"></variable>
 <variable name="tipo" access="read,write,required"></variable>
 </controller>
 </task>
 <transition name="t erro" to="Escreve erro na consola">
 <condition>tipo != 'mail'</condition>
 </transition>
 <transition name="t mail" to="envia email">
 <condition>tipo== 'mail'</condition>
 </transition>
 </task-node>
 <start-state name="start">
 <transition name="t start" to="decidir o destinatario"></transition>
 </start-state>
...

I'm creating the instance with:

cmd = new NewProcessInstanceCommand();
cmd.setProcessId(Long.parseLong(pid));
cmd.setActorId(getUser().getName());
cmd.setCreateStartTask(true);

Could anyone clarify a bit this issue.

Thanks in advance.

[vtysh]

Maybe you should signal to the process instance after creation to move from start state to first task node? Or try to add some actions to start-state, for example on node enter and perform signaling in it. But it is only in theory, i didn't use models without a task in start state.

[kukeltje]

correct

[syngolis]

hmm...

Maybe I am wrong, but I tested the node-enter behaviour on start-state and it seems, that this event is never executed:

<process-definition
 xmlns="" name="test5">
 <start-state name="start">
 <task name="task"></task>
 <event type="node-enter">
 <script>
 <expression>
 System.out.println("NODE-ENTER");
 </expression>
 </script>
 </event>
 <event type="node-leave">
 <script>
 <expression>
 System.out.println("NODE-LEAVE");
 </expression>
 </script>
 </event>
 <transition name="" to="end1"></transition>
 </start-state>
 <end-state name="end1"></end-state>
</process-definition>

I get only "NODE-LEAVE" output on my console. Is that correct?!?

[vtysh]

Seems that start-state doesn't have a node-enter event.

For ricardomarques: maybe you should use StartProcessInstanceCommand instead NewProcessInstanceCommand with cmd.setCreateStartTask(false);

[syngolis]

That's not really a good solution because you can't specify the behaviour by processdefinition.

While searching the source code i found:

public static final String[] supportedEventTypes = new String[]{
 Event.EVENTTYPE_NODE_LEAVE,
 Event.EVENTTYPE_AFTER_SIGNAL
 };

for start-state. So there really seems to be no ENTER event. But why? Anybody knows?

[vtysh]

You can use NewProcessInstanceCommand with createStartTask as true, if returned value will be null then you will know, that process doesn't contain a start task. Then you can use SignalCommand or some other one to move process from start state to first task node.

[syngolis]

Ok. Should work this way.

[koen.aers]

The node enter event gets fired when the token enters a node. As for the start-state, the token never enters it. Rather the token is *positioned* in the start-state when the process starts executing. So the event you want to look at is the process-start event.
Btw. Performing a signal on the current token from an action handler is not a good practice. Action handlers that are configured on events should not try to modify the execution of the token.

Regards,
Koen

[estaub]

Performing a signal on the current token from an action handler is not a good practice.

Koen,

You mean that to apply only to event-handling ActionHandlers, correct?

Node-execution ActionHandlers can signal, yes?

Thanks,
-Ed Staub

[syngolis]

Thank you for the hint! Process-Start-Event works fine.

Anyway, there seems to be no elegant way to skip the start-state except the programmatically
way that was mentioned by vtysh. And since there is no role assignment possible in start-state,
every workflow has to be signalled by initiator.

(Would be nice if there were a few more possibilites to use the start-state than now)

[ricardomarques]

"vtysh" wrote:
You can use NewProcessInstanceCommand with createStartTask as true, if returned value will be null then you will know, that process doesn't contain a start task. Then you can use SignalCommand or some other one to move process from start state to first task node.

i have take your idea and my my own Command based on NewProcessInstanceCommand to do this, this part is working now.


thanks for the feedback

[kukeltje]

@ed: Yes, correct...

[koen.aers]

Node-execution ActionHandlers should typically not call signal() but leaveNode(). The differences are minor though, if I remember correctly signal() only wraps leaveNode() adding the before-signal and after-signal event handling. But normally these events should not be handled on the node level.

Thanks,
Koen

[koen.aers]

As for skipping the start-state. You can start the process in any node from jPDL 3.2 on. Just do not model a start-state and add initial="true" as an attribute on the node (state, mail-node, process-state, etc) that you want to be the first node in the process-definition.

Regards,
Koen