Chapter 7C
Branch
A condition whose results provide transitions to different activity paths (diamond )
Activity:
Action that must take place for a process to be completed
Activity
Behavior that an object carries out while in a particular state (rounded rectangle )
Business Process Modeling Notation (BPMN):
Business process modeling approach established by the Object Modeling Group
Synchronous message:
Caller has to wait for the receiving object to finish executing the called operation before it can resume execution itself
DFDs:
Data flow, data store, source/sink, process Depicts the movement of data between external entities and the processes and data stores within a system • Show which processes move and transform data • Show which elements are inside/outside the system
Gateway:
Decision point
Activity Diagram Purpose
Depicts the flow of control from activity to activity • Help in "use case" analysis to understand what actions need to take place • Help in identifying extensions to a "use case" • Model work flow and business processes • Model the sequential and concurrent steps in a computation process
Sequence Diagrams
Depicts the interactions among objects during a certain period of time • May be presented in either generic form or instance form: • Generic form: Shows all possible sequences of interactions, corresponding to all scenarios of a use case • Instance form: Shows the sequence for only one scenario
Message:
Means by which objects communicate with each other
Objects:
Represented by boxes at top of diagram
Asynchronous message:
Sender does not have to wait for the recipient to handle the message
Sequence diagrams:
Show explicit sequencing of messages
Collaboration diagrams:
Show relationships among objects
Generic form:
Shows all possible sequences of interactions, corresponding to all scenarios of a use case
Instance form:
Shows the sequence for only one scenario
Flow:
Shows the sequence of action in a process
Business Process:
Standard method for accomplishing a particular task necessary for an organization to function
Elements of Activity Diagrams: A user wants to logon to a system
Start: The beginning of a process (filled in circle ) • Branch: A condition whose results provide transitions to different activity paths (diamond ) • Activity: Behavior that an object carries out while in a particular state (rounded rectangle ) • Merge: Where different paths converge (diamond ) • End: The end of a process (a filled in circle that has another circle around it )
Elements of Activity Diagrams: Customer Ordering Process
Swimlanes: Columns representing different organizational units of the system (vertical lines) Start: The beginning of a process (filled in circle) Activity: Behavior that an object carries out while in a particular state (rounded rectangle) Fork: Beginning of parallel activities (horizontal line with 2 arrows coming out of it) Branch: A condition whose results provide transitions to different activity paths (diamond) Merge: Where different paths converge (diamond) Join: End of parallel activities (horizontal line with 2 arrows coming into it) End: The end of a process (a filled in circle that has another circle around it)
Start
The beginning of a process (filled in circle )
End:
The end of a process (a filled in circle that has another circle around it )
Lifeline:
Time during which an object exists
Activation:
Time period during which an object performs an operation
• Simple message:
Transfers control from the sender to the recipient without describing the details of the communication
• Event:
Trigger that initiates the start of a process
Use case diagrams:
Use case, actor, connection, system boundary Show a system's available top-level functions for different types of users • Depicts system behavior along with the key actors that interact with the system
Merge:
Where different paths converge (diamond )
DFDs vs. Use Case Diagrams
• Elements: • DFDs: Data flow, data store, source/sink, process • Use case diagrams: Use case, actor, connection, system boundary • • DFDs: • Depicts the movement of data between external entities and the processes and data stores within a system • Show which processes move and transform data • Show which elements are inside/outside the system • Use case diagrams: • Show a system's available top-level functions for different types of users • Depicts system behavior along with the key actors that interact with the system
Activity Diagrams
• Show the conditional logic for the sequence of system activities needed to accomplish a business process •Clearly show parallel and alternative behaviors •Can be used to show the logic of a use case •What does an Activity Diagram look like?
Specialized Notation
• Specialized event notation (such as from message, or at particular time) • Specialized flow notation (sequence, default, or message flow)
Types of Messages
• Synchronous message: Caller has to wait for the receiving object to finish executing the called operation before it can resume execution itself • Simple message: Transfers control from the sender to the recipient without describing the details of the communication •Asynchronous message: Sender does not have to wait for the recipient to handle the message
Types of BPMN Gateways
• XOR: Exclusive OR gateway; only one of the paths that exit the gateway can be followed •AND: All of the paths that follow the gateway can be followed in parallel •OR: At least one path out of the gateway must be followed, but all paths that leave the gateway can be followed
Interaction Diagrams
•Used to show interactions among objects for a particular use case • Two types of interaction diagrams: • Sequence diagrams: Show explicit sequencing of messages • Collaboration diagrams: Show relationships among objects