Behavior Modeling State Diagrams

Transcripción

1 11/11/ State Behavior Modeling State Diagrams Software Engineering and Databases Group Department of omputer Languages and Systems University of Seville November 2015 La traducción de este material docente ha sido financiada mediante la convocatoria 1.10B - Ayudas de innovación y mejora docente, convocatoria , modalidad B del II Plan Propio de Docencia de la Universidad de Sevilla. No ha habido financiación alguna para este proyecto de otros soportes. Learning objectives 3. State Understand the basics of behavior modeling using UML state (statecharts). Be able to develop state from a requirements specification. 1 RE 1

2 11/11/2015 Models of a software system Static model (conceptual model) 3. State Describes the structure and constraints of the information representing the system state. Behavior model Describes how the system interacts with actors and how its state evolves as a result of the interactions. Model = + Static model = Behavior model = Structure + onstraints External interactions + Internal evolution 2 Behavior model of a software system 3. State External interactions Behavior model Internal evolution User Interface Service Interface System operations State must be consistent with 3 RE 2

3 11/11/2015 State in UML (statecharts) 3. State If the objects of a class have a number of clearly identified states, a state diagram can be associated to that class. stm Estado civil Soltero muere vuelve con 4 Elements of state 3. State States: represent relevant situations of the objects of a class in the problem domain. They are usually named as past participles. stm Elementos diagrama estados Estado 4 [condición 3] evento 2 [condición 1] creación 1 Estado 1 evento1 Estado 3 evento 2 [condición 2] Estado 5 Pseudoestado inicial creación 2 Final 1 Estado 2 Final 2 5 RE 3

4 11/11/2015 Elements of state 3. State Transitions: indicate from which state to which state an object can pass when some event is triggered and/or some condition (guard) is met. stm Elementos diagrama estados Estado 4 [condición 3] evento 2 [condición 1] creación 1 Estado 1 evento1 Estado 3 evento 2 [condición 2] Estado 5 Pseudoestado inicial creación 2 Final 1 Estado 2 Final State Special states: initial pseudostate It is the only state in which object creation events are accepted. There can only be one in a diagram. Not an actual state (the object does not exist yet). stm Elementos diagrama estados Estado 4 [condición 3] evento 2 [condición 1] creación 1 Estado 1 evento1 Estado 3 evento 2 [condición 2] Estado 5 Pseudoestado inicial creación 2 Final 1 Estado 2 Final 2 7 RE 4

5 11/11/2015 Special states: final states 3. State They do not have output transitions, i.e. they are states in which the object cannot evolve anymore. There can be several of them in a state diagram. stm Elementos diagrama estados Estado 4 [condición 3] evento 2 [condición 1] creación 1 Estado 1 evento1 Estado 3 evento 2 [condición 2] Estado 5 Pseudoestado inicial creación 2 Final 1 Estado 2 Final State Special states: composite states They are states containing other internal state diagram. They can be represented collapsed or expanded. stm Estado civil Soltero muere vuelve con 9 RE 5

6 11/11/ State Special states: concurrent states They are used when an object can be in several states at the same time. stm Estados concurrentes [Estado civil] Soltero vuelve con [Estado laboral] Desempleado lo contratan lo despiden Empleado Jubilado State Special states: concurrent states They are equivalent to a single state diagram with all possible state combinations. stm Estados concurrentes [Estado civil] Soltero vuelve con [Estado laboral] Desempleado lo contratan lo despiden Empleado Jubilado 11 RE 6

7 11/11/ State Alternative representation: enumerations The object state can also be represented by an enumerated attribute. stm Statechart A B class Ejemplo statechart estado: Estado A B «enumeration» Estado State Alternative representation: enumerations Each concurrent region and each composite state stm Estados concurrentes need its own attribute and enumerated type. [Estado civil] Soltero vuelve con class Ejemplo statechart Persona estado: EstadoPersona estadoivil: Estadoivil estadolaboral: EstadoLaboral [Estado laboral] Desempleado lo contratan lo despiden Jubilado Empleado «enumeration» EstadoPersona «enumeration» Estadoivil vivo «enumeration» EstadoLaboral Soltero Desempleado Empleado Jubilado 17 RE 7

8 11/11/2015 Alternative representation: Booleans 3. State Each state can be represented by a Boolean attribute. The statechart structure is represented by invariants. stm Statechart A B class Ejemplo statechart a: boolean b: boolean c: boolean {EstructuraStatechart : a xor b xor c} State Bibliography. Larman, UML y Patrones. Ed. Prentice-Hall, hapters 9 to 12. Larman, UML y Patrones (2ª edición). Ed. Prentice-Hall, hapters 10 to 12 D. D Souza y A. Wills, Objects, omponents, and Frameworks with UML: The atalysis Approach. Ed. Addison-Wesley, hapter 3 19 RE 8

9 11/11/2015 omments, suggestions, State 20 RE 9