I am using commons SCXML2 having States and tasks to control the Workflow Engine and initially the engine starts with a initial State and execute State and task in a flow.
And our requirement is that we want to persist the State if the Workflow get exited.
We are storing the State in the Database from which we want to resume the Workflow.
Now i am unable to resume the Workflow with the given State.
what i tried...
SimpleTransition initialTransition = new SimpleTransition();
initialTransition.setNext("first"); //jumping to First State
exec.getStateMachine().setInitialTransition(initialTransition);
I am unable to find how to jump to given state and used the above code to do so but it does not help for me.
Related
I have a state machine diagram for an application that has a UI and a thread that runs parallel. I model this using a state with 2 parallel regions. Now I want when that thread gives some message, for example an error, that the state of the UI changes, for example to an error screen state.
I was wondering what the correct method to do this is, as I was not able to find any example of this situation online.
The options that I thought of were creating a transition from every state to this error state when the error state is called, which in a big diagram would mean a lot of transitions. Or by just creating a transition from the thread to the error state (As shown in the image), which could possible be unclear.
Example of second option
You don't need a transition from every state. Just use a transition from the State State to the Error window state. It will then fire no matter what states are currently active.
Such a transition will also leave the Some process state. Since you didn't define initial states in the orthogonal regions, the right region of the state machine will then be in an undefined state. Some people allow this to happen, but for me it is not good practice. So, I suggest to add initial states to both regions. Then it is clear, which sub state will become active, when the State state is entered for any reason. The fork would also not be necessary then.
How you have done it in your example would also be Ok. However, since the Some process state is left by this transition, this region is now in an undefined state. Again, the solution to this is to have an initial state here. I would only use such a transition between regions, when it contains more than one state and the On error event shall not trigger a transition in all of the states.
If the Some process state is only there to allow for concurrent execution, there is an easier way to achieve this: The State state can have a do behavior, that is running while the sub states are active. Orthogonal regions should be used wisely, since they add a lot complexity.
I have two processes I want to juxtapose. The first is a Manual workflow that is well represented by the Process library. The second is a software System that performs the same work, but is better modelled as a state transition system (e.g. s/w component level).
Now in AnyLogic, state models are for agents, that can run through processes with animations (counts), or move across space. What if I want to use a state chart to run an agent through? so I have a System state chart/agent and a Job state chart/agent?
I want Jobs from Population A to go through the Manual process flow chart and Jobs from Population B to go through the System state flow chart, so I can juxtapose the processing costs. I then calculate various delays and resource allocations for each of the Jobs going through and compare them.
Can anyone explain how to setup a state chart as the base process, another agent will go through? Is this even possible?
Please help
Thanks
This will not work as you would like it to, for these reasons:
You can't send an Agent into a flowchart. (Not sure how AnyLogic is handling it internally, maybe a generic token, or no flow at all, just changes to the state).
In AnyLogic there can only be one state active (simple or combined state) per state chart, so you can't represent a population with several members.
Agents can't be in more then one flow at a time, so even if it would be possible to insert an Agent into a statechart, this limitation would also apply.
The conclusion of this is: State charts are suitable for modeling individual behaviour (inside one Agent), whereas process flows can be both used for individual behaviour (inside one Agent, running a dummy Agent through) as well as for groups (multiple Agents running through process).
The normal use case would be to add the state chart to the Agent type running through your process flow (as you already noted in your question), applying the changes caused by the state chart to the individual agent.
I'm facing an annoying issue in Blueprism a little help will be appreciated.
The error is when I run the task I have created in object studio directly in object studio it runs successfully but when I try to run the same task from process studio using action It throws an error. The application is launched but get this error. (Application is web-based.)
Internal: Failed to perform step 1 in Read Stage 'Reader1' on page 'Main' - No elements match the supplied query terms
this is Application Modeller Settings
Application Modeller
And this is how I call it in Process
Object Called in process
Action Properties
Wait Settings are following
When I try to highlight the link it does highlight it.
I think that after your Reader1 should be a decision if element was found or not and then you can proceed with log-in. But I'd check if the element you're spying is working correctly. Maybe try passing value of reader from object to process.
A process in BluePrism can have different speed of execution depending on the way you're running it.
If you're running application using "Step" function (hotkey F5), then BluePrism waits a long time between executing actions. A "Step above" (hotkey F10) is much faster, but the fastest possible speed of execution is from control room.
The delay from "Step", or "Step above" can be enough to make process work during the development. Once the process is moved to control room, then the delay is gone and sometimes the process might be running too fast. It can happen, that the BluePrism is trying to interact with the element that does not yet exist.
To make process work in control room, you need to have additional wait stages that will ensure that the process is not running ahead of the applications that are being automated. Whenever you're interacting with any element then you need to be sure that it exists.
i suspect that you're waiting for an element, but then you're trying to read a different one. It's important to wait for the exact element that you want to interact with, as elements can appear in an order, that can make your process crash.
Following on the discussion at State machine program design in FreeRTOS - vTaskStartScheduler in a switch statement, I have a state machine with 4 states, each of them with different tasks reading sensor data.
When a sensor data reaches a threshold, its task has to cause a state change.
The idea is to have a superior task which controls the states (and suspends/resumes corresponding tasks) with a switch statement. My question is: how should the sensor tasks communicate the STATE with the superior task?
One proposed solution is to have a set_state function which is called by the event generating task, but I read that having global variables in FreeRTOS is discouraged. I thought to implement it through Queues:
1- Task1 detects sensor threshold, and sends STATE to a Queue.
2- Superior task is blocked waiting to receive data from Queue. When it receives STATE, the switch statement processes the state change.
If this approach is correct, my doubt relates on how and where should be STATE defined (global, or just existing in the stack of each task, or the superior task...)
STATE should exist only where it needs to, 'in' the superior task. I'm presuming you're using C, so declare STATE as a static variable in "superior_task.c" (or whatever it's called). This means it can then only be affected within that file - the C equivalent to a private member variable in C++.
Then, if your inferior tasks need to affect a state change, they post a state change event to a queue managed by the superior task. When the queue is processed, the superior state makes the change to the private STATE variable.
If other tasks need to know what the state is for their own processing, they can use an accessor for the private variable, e.g., State get_state() { return STATE; }. As Martin says though, the other tasks shouldn't need to know the state, as otherwise there's inter-dependencies between tasks that shouldn't exist.
I am very new to this subject, please let me know if you need more context.
I have an old legacy system with lots of complicated business logic/states that we are trying to extract and re-implement in a state machine.
Let's suppose I need to do something similar:
Save a User to the state "Approved"
Reject if the user data does not satisfy some conditions
Accept the change otherwise, save the User and send a notification
My understanding is that between 1. and 2. I need to call the state machine providing the new data (filled from a web form).
The state machine needs to get the current state from the database to understand what is the original state and verify if the conditions for switching the state to "Approved" are met.
Is my understanding right?
Thank you