Question: Describe the concept of concurrent state diagram.

Subject: Object Oriented Modeling and Design

Difficulty: Medium

Marks: 4 Marks

diploma • 16 views
modified 5 days ago  • written 16 days ago by gravatar for Ankit Pandey Ankit Pandey ♦♦ 0
  • Concurrent state diagram shows a set of independent behaviors of an object.
    • Concurrent sub states are independent and can execute in parallel. A state may be divided into regions containing sub-states that exist and execute concurrently.
    • UML shows concurrency within an object by partitioning the composite state into regions with dashed lines.

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  • In the above example, concurrent sub states are shown. Maintenance is a composite state. It is decomposed into two concurrent sub-states as testing and commanding.
  • Each of these concurrent sub-states is further decomposed into sequential sub-states.
  • When control passes from Idle to Maintenance state, control then forks to two concurrent flows.
  • Execution of these two concurrent sub-states continues parallel in the system. Each nested state machine reaches its final state.
  • If one concurrent sub state reaches its final state before the other, then control in that sub-state waits at its final state.
  • When both nested state reaches their final state, control from the two concurrent sub-states joins back into one flow.
written 5 days ago by gravatar for Ankit Pandey Ankit Pandey ♦♦ 0
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