Class Diagram of Blog

        In software engineering, a class diagram in the Unified Modeling Language (UML) is a type of static structure diagram that describes the structure of a system by showing the system's classes, their attributes, operations (or methods), and the relationships among objects.
Definition Of The Class Diagram
Class is a collection of objects with a common structure and common behavior, public relations, and semantic/common words. Class-class determined/found by way of checking objects in sequence diagrams and collaboration diagrams. A class is represented as a square with three sections of the room. Class should be named using the noun corresponding to domain/section/group (Jeffery l. Whitten et al, 2004).
The Class Diagram is a diagram that shows the existing classes of a system and its relationship to logic. Class diagram describes the static structure of a system. Therefore the class diagram is the backbone or the strength of the Foundation of almost every object-oriented methods including UML (Henderi, 2008). While according to (Jeffery l. Whitten et al. 2004: 432) class diagram is a graphical picture of the structure of a static object system, indicating the classes of objects that make up a system and also the relationship between the object class.
Class diagrams are visual representations of the static structure and composition of a particular system using the conventions set by the Unified Modeling Language (UML). Out of all the UML diagram types it is one of the most used ones. System designers use class diagrams as a way of simplifying how objects in a system interact with each other. Using class diagrams, it is easier to describe all the classes, packages, and interfaces that constitute a system and how these components are interrelated. For example, a simple class diagram may be used to show how an organization such as a convenient store chain is set up. On the other hand, precisely detailed class diagrams can readily be used as the primary reference for translating the designed system into a programming code.
Component Class Diagram
1. Subsystem
While a package is a mechanism for organizing the common element-element models, subsystems describes a unit of behavior in physical systems.
2. Class
A class is the description for a set of objects with similar structure, behavior, and behavior/relationship/relation.
3. the Interface
An interface is to specify an externally-visible operations of a class, component, or other penggolong/classifier (including subsystems) without the specification of the internal structure.
4. Signal
Signal is one which describes the specification of asynchronous stimulus communicated between instances.
5. Exception
An Exception is a signal raised by behavior in a when an error occurs.
6. Port
Port is a structural one peng-class, which defines a difference that shows interactions between peng-class's and their environment or between (behavior) peng-class and its internal parts.
The class diagram is the main building block of object oriented modelling. It is used both for general conceptual modelling of the systematics of the application, and for detailed modelling translating the models into programming code. Class diagrams can also be used for data modeling.[1] The classes in a class diagram represent both the main objects, interactions in the application and the classes to be programmed.
Determine the class
A good way to find classes were started from watching the flow of events ( flow of events ) of a use case . Note the noun in the flow of events , may be one of the following four points .
1 . Actor
2 . class
3 . Attributes of the class
4 . Expression , not the actor , not a class , and not attributes .
By selecting the object in the flow of events , classes can be found in the system . Other alternatives , can test objects in sequence diagrams and collaboration diagrams .
There are two common ways of defining sequence of inter -related classes in the class diagram and sequence diagram or a collaboration diagram . The first , by creating a sequence diagram or a collaboration diagram first . Then proceeded to create the class diagram . In contrast , the second , is to find classes and create class diagrams first, then use a stretcher classes as " Dictionary " objects and their relationships to create a sequence diagram or a collaboration diagram .
Elements-elements relevant in modeling UML class diagram consists of: classes, class structure, the nature of class (class behavior), association / union (association), collection / unity (aggregation), dependency (dependency), derivatives relations, diversity and navigation indicators, and role name (role / task name).
In the design of a system, a number of classes are identified and grouped together in a class diagram which helps to determine the static relations between those objects. With detailed modelling, the classes of the conceptual design are often split into a number of subclasses.
In order to further describe the behaviour of systems, these class diagrams can be complemented by state diagram or UML state machine.[2]
In software engineering, a class diagram in the Unified Modeling Language (UML) is a type of static structure diagram that describes the structure of a system by showing the system's classes, their attributes, operations (or methods), and the relationships among objects.