Chapter 7 Behavioral Modeling Brandon A. Jones Stand and Deliver ITEC March 6, 2011

Quick Recap Functional Modeling: ▫Describing the external behavioral view of an information system  Processes that are preformed and how information moves among them. Structural Modeling ▫Depicting the static view of an information system.  People, places, things from which info is obtained, and how they relate.

What is Behavior Modeling? Behavior modeling describes internal behavior or the dynamic view of information systems. Two types of Behavioral Models ▫Interaction Diagrams and Behavioral State Machines Each model represents underlying data of a business process. ▫Interaction Diagrams: underlying data portrayed by use case ▫State Machine: illustrates changes in underlying data

Interaction Diagrams Interaction v Class Diagrams ▫Modeling Focus:  Class Diagrams – Class Level  Interaction Diagrams – Object Level What is an Object? ▫Representation of a class; can be a person, place, or thing from which information is gathered.

Interaction Diagrams What is an Object? ▫Each object has attributes  Describes information about the object ▫Each object has behaviors  Described by operations, or actions that an object can preform. ▫Each object can also send and receive messages.  Simply, information sent to an object telling it to execute a behavior.  Conditions, Return Messages, Self-Delegation,

Sequence Diagrams Illustrate the objects involved in a use case and the messages that pass between them over time for one use case. Emphasize time based ordering of activities that take place among objects. Generic Sequence v Instance Sequence

Sequence Diagrams Elements of the Diagram ▫Actors –Person/system that benefits from and is external to system ▫Lifeline – denotes life of an object during sequence ▫Execution Occurrence – denotes when object is sending/receiving message ▫Guard Condition- a test that must be met for message to send ▫Object Destruction – x – end of objects lifeline, end of objects existence.

Building A Sequence Diagram Six step process ▫Identify the context ▫Identify participating objects ▫Establish lifelines ▫Add messages ▫Insert execution occurrence ▫Validate the diagram

Communication Diagrams Provide a view of the dynamic aspects of on an object-oriented system. Used to model all interactions among a set of collaborating objects. ▫Portraying how dependent different objects are to one another. ▫Shows message passing relationships. Useful for showing process patterns.

Communication Diagrams Elements of the Diagram ▫Actor ▫Object ▫Association – shows relationship between actors and/or objects. ▫Message ▫Guard Condition ▫Frame – Identifies context

Building A Sequence Diagram Five Step Process ▫Identify the context ▫Identify objects (actors) and associations that collaborate. ▫Lay out objects on diagram by placing them together. ▫Add messages to associations between objects. ▫Validating the diagram.

Behavioral State Machines Dynamic model that shows different states through which object passes during its life in response to events, along with its response and actions. Should be used to further understand the aspects of a single class and its evolution over time. Shows different states of object and what caused the object to change from one state to another.

Behavioral State Machines What is the state of an object? ▫The value of its attribute and its relationships with other objects a particular time.  Depicted by state symbol Initial State – small filled in circle Final State – a bull’s-eye

Behavioral State Machine Elements of the BSM ▫Event – noteworthy occurrence that triggers a change in state. ▫Transition – indicates that an object in the first state will enter the second state.

Building A Behavioral State Machine Five Step Process ▫Identify the context ▫Identify various states object will have over its lifetime. ▫Determine sequence of the states the object will pass through ▫Identify events, actions, and guard conditions associated with transitions between states. ▫Validate the behavioral state machine.

CRUD Analysis CRUD matrix ▫C – Create ▫R – Read or reference ▫U – Update ▫D – Delete CRUD analysis can be used to identify complex objects. ▫C - Create ▫U – Update ▫D - Delete

Chapter 7 Behavioral Modeling Brandon A. Jones Stand and Deliver ITEC March 6, 2011