The\u00a0Unified Modeling Language<\/b>\u00a0(UML<\/b>) is a general-purpose, developmental,\u00a0modeling language<\/a>\u00a0in the field of\u00a0software engineering<\/a>\u00a0that is intended to provide a standard way to visualize the design of a system.<\/sup><\/p>\n The creation of UML was originally motivated by the desire to standardize the disparate notational systems and approaches to software design. It was developed at\u00a0Rational Software<\/a>\u00a0in 1994\u20131995, with further development led by them through 1996.<\/sup><\/p>\n In 1997, UML was adopted as a standard by the\u00a0Object Management Group<\/a>\u00a0(OMG), and has been managed by this organization ever since. In 2005, UML was also published by the\u00a0International Organization for Standardization<\/a> (ISO) as an approved ISO standard.\u00a0<\/sup>Since then the standard has been periodically revised to cover the latest revision of UML.<\/sup>\u00a0In software engineering, most practitioners do not use UML, but instead produce informal hand drawn diagrams; these diagrams, however, often include elements from UML.<\/p>\n In\u00a0software engineering<\/a>, a\u00a0class diagram<\/b>\u00a0in the\u00a0Unified Modeling Language<\/a>\u00a0(UML) is a type of static structure diagram that describes the structure of a system by showing the system’s\u00a0classes<\/a>, their attributes, operations (or methods), and the relationships among objects.<\/p>\n The class diagram is the main building block of\u00a0object-oriented<\/a>\u00a0modeling. It is used for general\u00a0conceptual modeling<\/a>\u00a0of the structure of the application, and for detailed modeling, translating the models into\u00a0programming code<\/a>. Class diagrams can also be used for\u00a0data modeling<\/a>. The classes in a class diagram represent both the main elements, interactions in the application, and the classes to be programmed.<\/p>\n In the diagram, classes are represented with boxes that contain three compartments:<\/p>\n In the design of a system, a number of classes are identified and grouped together in a class diagram that helps to determine the static relations between them. In detailed modeling, the classes of the conceptual design are often split into subclasses.<\/p>\n In order to further describe the behavior of systems, these class diagrams can be complemented by a\u00a0state diagram<\/a>\u00a0or\u00a0UML state machine<\/a>.<\/p>\n An\u00a0object diagram<\/b>\u00a0in the\u00a0Unified Modeling Language<\/a>\u00a0(UML), is a\u00a0diagram<\/a>\u00a0that shows a complete or partial view of the structure of a modeled\u00a0system<\/a>\u00a0at a specific time.<\/p>\n In the\u00a0Unified Modeling Language<\/a>\u00a0(UML), an object diagram focuses on some particular set of\u00a0objects<\/a>\u00a0and\u00a0attributes<\/a>, and the links between these instances. A correlated set of object diagrams provides insight into how an arbitrary view of a system is expected to evolve over time. In early UML specifications the object diagram is described as:<\/p>\n The latest UML 2.5 specification does not explicitly define object diagrams\u00a0<\/span>but provides a notation for instances of classifiers.<\/p>\n Object diagrams and class diagrams are closely related and use almost identical notation. Both diagrams are meant to visualize static structure of a system. While class diagrams show\u00a0classes<\/a>, object diagrams display instances of classes (objects<\/a>). Object diagrams are more concrete than\u00a0class diagrams<\/a>. They are often used to provide examples or act as test cases for class diagrams. Only aspects of current interest in a model are typically shown on an object diagram.<\/p>\n A\u00a0sequence diagram<\/b>\u00a0or\u00a0system sequence diagram<\/b>\u00a0(SSD) shows\u00a0process<\/a>\u00a0interactions arranged in time sequence in the field of\u00a0software engineering<\/a>. It depicts the processes involved and the sequence of messages exchanged between the processes needed to carry out the functionality. Sequence diagrams are typically associated with use case realizations in the\u00a04+1 architectural view model<\/a>\u00a0of the system under development. Sequence diagrams are sometimes called\u00a0event diagrams<\/b>\u00a0or\u00a0event scenarios<\/b>.<\/p>\n For a particular scenario of a\u00a0use case<\/a>, the diagrams show the events that external actors generate, their order, and possible inter-system events. All\u00a0systems<\/a>\u00a0are treated as a\u00a0black box<\/a>; the diagram places emphasis on events that cross the system boundary from actors to systems. A system sequence diagram should be done for the main success scenario of the\u00a0use case<\/a>, and frequent or complex alternative scenarios.<\/p>\n","protected":false},"excerpt":{"rendered":"Class diagram<\/h3>\n
\n
Object diagram<\/h3>\n
\n
Sequence diagram<\/h3>\n