Filip Stachecki: /* Composition⌘ */

2013-10-24T07:40:00Z

Composition⌘

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[[Category:Private]]
[[Category:OCUP]]
==Class Basics⌘==
Described in the metamodel Kernel package Classes::Kernel.

Most elements of the root model are abstract and are not represented in UML diagrams.
====Element⌘====
[[File:UMLElement.png]]

Metaclass '''''Element'''''
*An element is a constituent of a model.
*All elements are subclasses of Element
*Element can own other elements
*No notation for Element - it is ''abstract''
====Relationship ⌘====
[[File:UMLRelationship.png]]

'''''Relationship''''' class
*Used to interconnect elements
*No notation for Relationship as it is ''abstract''

====Directed Relationship ⌘====
[[File:DirectedRelationship.png]]

'''''DirectedRelationship''''' class
*a specialization of a relationship
*source elements want something - a '''client'''
*target element offers something - a '''supplier'''

===Comment⌘===
[[File:UMLComment.png]]
* a textual annotation that can be attached to an element
* may contain information that is useful to a modeler
* can be attached to more than one element

===Constraint⌘===
[[File:Constraint.png]]
* condition or restriction related to an element
* it must always be true
* can be in formal (OCL) or human language
* syntax:
'''{''' [name :] boolean expression '''}'''

===Classifier⌘===
* an abstract base class
* describes a set of instances that have features in common
* Examples of Classifiers:
** Use Case
** Class
===Feature⌘===
[[File:Feature.png]]
* declares a behavioral or structural characteristic of instances of classifiers
* '''structural feature''' describes a structure of an instance of a classifier (e.g. property)
* '''behavioral feature''' specifies an aspect of the behavior of classifier's instances (e.g. operation)
====Property⌘====
* a special structural feature that if it belongs to a class, is an attribute
* represents a declared state of one or more instances

====Operation⌘====
* a behavioral feature of a classifier, which specifies name, type, parameters, and constraints
* can have preconditions and postconditions
* can have a type (the type of the return parameter)
* example:
+ createWindow (location: Coordinates): Window

===Class⌘===
[[File:UMLClass.png]]
* describes a set of objects that share the same specifications of features (attributes and operations)
* is a special classifier
* an object is an instance of a class

===Generalization⌘===
[[File:GeneralizationExample.png]]
* relationship between a more general classifier and a more specific classifier
* each instance of the specific classifier is also an indirect instance of the general classifier
* the specific classifier inherits the features of the more general classifier
====Generalization Example⌘====
[[File:GenExample.png]]

===Association⌘===
[[File:AssociationWithMarks.png]]
* specifies a relationship between instances
* describes a set of tuples whose values refer to typed instances
* declares that there can be links between instances of the associated types

====Multiplicity⌘====
* specifies how many objects of the opposite class an object can be associated with
* is a range of the minimum and maximum values
* syntax: '''number''' or '''min..max'''
{| class="wikitable"
|-
! Multiplicity !! Notation
|-
| zero || '''0''' or '''0..0'''
|-
| exactly one || '''1'''
|-
| zero or one || '''0..1'''
|-
| zero or more || '''0..*''' or '''*'''
|-
| one or more || '''1..*'''
|}

====Multiplicity example⌘====
[[File:MultiplicityExample.png]]

====Multiplicity - order and uniqueness⌘====
* Multiplicity defines a specification of order and uniqueness of the collection elements.
* This option can specify whether the values should be '''unique''' and/or '''ordered'''.
** '''ordered''': the collection of values is sequentially ordered (default: not ordered)
** '''unique''': each value in the collection of values must be unique (default: is unique)

====Property = End or Attribute⌘====
[[File:Attribute.png]]

====Navigability⌘====
[[File:Navigability.png]]
* specifies whether one object can be accessed directly from another

====Aggregation⌘====
[[File:Aggregation.png]]
* shows how something ('''whole''') is composed of '''parts'''
* parts can exist separately - can be '''shared'''
* precise semantics of aggregation varies by application area and modeler :)

====Composition⌘====
[[File:UMLComposition.png]]
* a strict form of aggregation
* the whole is the owner of its parts
* parts '''can not''' be shared
* the existence of its parts depends on the whole

====Aggregation / Composition Example⌘====
[[File:AggregationBoatCarExample.png]]

====N-ary association⌘====
[[File:TernaryAssociation.png]]
* if an association has more than two end points (here: ternary association)
* Notation: a rhombus is used as a connection point

===Dependency ⌘===
[[File:Dependency.png]]
* a relationship that signifies that a model element(s) requires other model element(s) for their '''specification''' or '''implementation'''
* the complete semantics of the depending elements is dependent on the definition of the supplier element(s)
* the modification of the '''supplier''' may impact the '''client''' model elements
* the semantics of the '''client''' is not complete without the '''supplier'''
* the type of dependency can be specified by using a keyword or stereotype

====Abstraction⌘====
[[File:Abstraction.png]]
* a special dependency relationship between model elements that represent the '''same concept''' at '''different levels''' of abstraction or from '''different viewpoints'''

====Permit⌘====
[[File:Permit.png]]
* the dependent element is permitted to use '''private''' content of this independent element

====Substitute⌘====
[[File:Substitute.png]]
* instances of the independent element can be substituted by instances of the dependent element at runtime
* runtime substitutability that is not based on specialization

====Usage⌘====
[[File:UsageRelationship.png]]
* a relationship in which one element requires another element(s) for its full '''implementation'''
* is limited to the '''implementation''' and it doesn’t apply to the specification (dependency do apply)

===Interface⌘===
* is a kind of classifier that represents a '''declaration''' of a set of coherent public features and obligations
* an interface specifies a '''contract'''; any instance of a classifier that realizes the interface must satisfy that contract
* it is just declaration - so it is '''not instantiable'''

====Provided Interface⌘====
[[File:ProvidedInterface.png]]
* an interface realized by a classifier is its '''provided interface'''
* represent the obligations that instances of that classifier have to satisfy

====Required Interface⌘====
[[File:RequiredInterface.png]]
* specify services that a classifier '''needs''' in order to perform its function
====Interface Example⌘====
[[File:InterfaceExample.png]]

===Named Element⌘===
* represents an element that '''may''' have a name and a visibility
{| class="wikitable"
|-
! Visibility Kind !! Notation
|-
| public || '''+'''
|-
| private || '''-'''
|-
| protected || '''#'''
|-
| package || '''~'''
|}

===Namespace⌘===

*named element that can own other named elements
*each named element may be owned by at most one namespace
* provides a container for named elements
* all the members of a '''namespace''' are distinguishable within it

===Package⌘===
[[File:UMLPackage.png]]
* used to group elements, and provides a namespace for the grouped elements
* qualified name:
package name::element name

===Package Import, Access⌘===
[[File:PackageImportAccess.png]]

A package import is defined as a directed relationship that identifies a package whose members are to be imported by a
namespace.

Two types:
* «import» for a '''public''' package import
** transitive: if A imports B and B imports C then A indirectly imports C
* «access» for a '''private''' package import
** intransitive

====Package Import Example⌘====
[[File:PackageImportExample.png]]
* elements in Types are imported to ShoppingCart, and then further imported to WebShop
* elements of Auxiliary are only accessed from ShoppingCart, and cannot be referenced from WebShop

===Instance ⌘===
[[File:InstanceSpecification.png]]
* is a concrete instance in the modeled system
* instance = object

OCUP Class Diagram - Revision history

Filip Stachecki: /* Composition⌘ */