SysMLv1: Cameo Simulation Toolkit: Activity Diagram simulation: Tokens in a CentralBufferNode [with mini video]

Gallery
Tutorial
TRAIL: SysMLv1/UML: Cameo Simulation Toolkit® (Magic Model Analyst®): Some basics for beginners and some more advanced cases [with mini videos]
Section
Topic level
INTERMEDIATE
UML keywords
Activity
CentralBufferNode
token
token offer
object token
SysML keywords
Block
value property
Keywords
Slide kind
SysML Activity Diagram
SysML Block Definition Diagram (BDD)
According to the following BDD fragment and Activity Diagram with a CentralBufferNode, how many DataToken tokens will still be in the «centralBuffer» AFTER a DataToken from the store is printed?
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UML2.5.1: '15.4.3.3 Central Buffer Nodes - A CentralBufferNode acts as a buffer between incoming ObjectFlows and outgoing ObjectFlows. It accepts all object tokens offered to it on all incoming flows, which are then held by the node.'
UML2.5.1: 'Held object tokens are offered to outgoing flows according to the general ordering rules for ObjectNodes. When an offer for a token is accepted by a downstream object node, that token is removed from the CentralBufferNode and moved to the accepting ...'

The initial “loop” will place 3 DataToken tokens in the CentralBufferNode. There will only be 2 DataToken tokens in the CentralBufferNode after the OpaqueAction print("ds") has accepted a token offer, because offered tokens are removed from a CentralBufferNode.

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SysMLv1: Cameo Simulation Toolkit: Activity Diagram simulation: Tokens in a DataStoreNode [with mini video]
Magic Model Analyst® (Cameo Simulation Toolkit®) (v2024x) actually has a minor bug not shown in the video. It correctly indicates the number of tokens in the CentralBufferNode as 2 after the OpaqueAction for print("ds") has accepted a token offer (with Show Held Tokens in Activity Diagrams enabled). However, if you hold you mouse over the «centralBuffer» Symbol, it incorrectly still shows 3 DataToken objects in the buffer with their respective 'i' values!
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SysMLv1: Cameo Simulation Toolkit: Activity Diagram simulation: Tokens in a DataStoreNode [with mini video]
Notes
Snippets (quotes/extracts)
  [UML-2.5.1] 15.4.3.3 Central Buffer Nodes - A CentralBufferNode acts as a buffer between incoming ObjectFlows and outgoing ObjectFlows. It accepts all object tokens offered to it on all incoming flows, which are then held by the node.
  [UML-2.5.1] Held object tokens are offered to outgoing flows according to the general ordering rules for ObjectNodes. When an offer for a token is accepted by a downstream object node, that token is removed from the CentralBufferNode and moved to the accepting ...
Related slides (includes other tutorials)
Related slides (backlinks, includes other tutorials)
SysMLv1: Cameo Simulation Toolkit: Activity Diagram simulation: Tokens in a DataStoreNode [with mini video]
Visit also
Course: Model-Based Systems Engineering with the OMG's Systems Modeling Language® (v1) and the MagicDraw/Cameo (CATIA Magic™) tools for SysML
01:04: UML Behavior: Activities quick start
UML2 Activity Diagram - essential metaclasses - ADVANCED REFERENCE ONLY
UML2 Actions - metaclasses - ADVANCED REFERENCE ONLY
TRAIL: UML Behavior: Activities and Actions
SysMLv1: Cameo Simulation Toolkit: HOWTO: Send a Signal via a nested Port using InvocationOnNestedPortAction and 'onNestedPort' together with 'onPort' [with mini video]
SysMLv1: Cameo Simulation Toolkit: HOWTO handle sending and receiving families of related Signal types with reuse of send/receive and processing logic [with mini video]
SysMLv1: Cameo Simulation Toolkit: HOWTO send a Signal via a Port to an intended recipient via a mediating secure RoutingHub [with mini video]
Visit also (backlinks)
External links
HIGH RESOLUTION version on Vimeo