1' Objects

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1. Objects UMLUnified Modeling Language

• Objects
• advantages
• Terms Concepts (standard sec 2)
• Object Orientation with UML
• examples of objects
• how expressed in UML
• UML language parts
• Class Diagrams
• Use Cases
• Sequence Diagrams
• Physical Representation
• deployment diagram specific for embedded systems
• Common things

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1.1 Objects

• Advantages
• consistency of model views
• improved model-domain abstraction
• improved stability at changes
• facilities for reuse
• improved scalability
• better support for reliability safety concerns
• inherent support for concurrency
• Disadvantages
• immature technology
• inefficient
• lack of compiler tool support
• Evolution
• mature, better tools, faster

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1.1a Objects

• Consistency
• same model views used in all development phases
• Improved problem domain abstraction
• data items operations stay together
• changes, reuse
• OO close to real world components
• aggregation, generalization, parameterization
• scalability, reliability, safety concerns
• encapsulation gt loose coupling well defined
  interfaces
• concurrency
• fact of life
• drawings inherently concurrent
• cf. bond graphs

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1.2 Terms Concepts

• Object
• unique real-world or conceptual entity
• identity, attributes (values), behaviors
  (operations)
• objects are instances of classes
• Classes
• abstraction of common things (type)
• class relations taxonomies
• association communication via messages
• Messages
• abstraction of object communication
• calls to operations
• Use cases
• functions of a system
• scenario specific path thru a use case
• actor object outside system

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1.3 Object Orientation with UML

• Unified Modeling Language
• Object Management Group
• OOSE (Booch, Jacobson), OMT (Rumbaugh)
• Others
• ROOM (Selic)
• Ward Mellor, Hatley Pirbhay, real-time Yourdon
• Modeling real-time Embedded Systems
• Object model, (data structure)
• Use cases, scenarios,
• State charts (behavior)
• Packaging
• Tasking / Task synchronization
• Deployment (physical topology)
• Patterns

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1.3a Objects

• Data behavior
• Attributes (data)
• Behavior (operations or methods)
• active, passive objects
• interface, methods
• simple, automaton (FSM), continuous (DFD)
• sending messages for calling services
• function call, interrupt, rendezvous, rpc
• State (memory)
• Identity
• Responsibilities (background info functions)
• Object
• Autonomous machine
• Data Type (ADT) Operations
• Combine properties into one cohesive entity

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1.3b Examples of Objects / Classes

• Abstraction
• objects --gt classes

Animal
weight height top speed
Polygon
attributes
vertices border color fill color
eat locomote respond
behaviors
draw erase move
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1.4 Class Diagrams

• Relations
• Association
• bi-directional exchange
• Aggregation
• contains
• Composition
• includes (part of)
• cannot be shared
• Generalization (inheritance)
• kind of
• Dependency
• refinement
• generalization

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1.5 Use Cases

• How to use the system
• context diagram
• actor
• object from outside
• use case
• function of system

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1.6 Sequence Diagrams

• How internal objects collaborate
• 1) Understand use cases
• extract requirements
• 2) Testing object structures
• responsibilities OK?

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1.7 Physical Representation
TMS 320LF2407 ltlt controllergtgt

• Specific for ES
• Deployment diagram
• mapping on computer hardware
• nodes connections
• ltltdevicegtgt, ltltprocessorgtgt
• componentdeployable software unit
• Component diagram
• static organizations of software

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1.8 Common things to diagrams

• Notes
• comments
• Packages
• logical grouping often domains
• Constraints
• additonal conditions c timing constraints on
  Seq Diag
• Stereotypes
• extension of the UML
• ltlt st.t. gtgt name

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1.8a Stereotypes for ES

• ES deployment
• Devices Nodes
• Icons for elements
• processors
• devices
• model details