Week 7
UMLApplication developers face the problem that standard modeling tools are goodFor communicating the results of a modeling process, but fail to support the process itself adequately.In a functional language everything is expressed as a function and all valueshave only single assignment. This is a major deference to modern high levelProgramming languages, where it is possible for instance to assign dierent valuesto variables Advantages of UMl:The basic advantage of using a framework is that good frameworks make application development a lot easier. It reduces the load on the developer by handling most of the more difficult programming related stuff and allows the developer to refuse analysis design implementation in a relatively straightforward way. The means that programming gets somewhat easier and even a junior programmer can produce a good frame work is very difficult and most existing frameworks are not good enough to live up to the expectations.Why it is an advantage.It is an advantage because Verification and validation checks are also organized according to these three modeling spaces, making it easier for the reader to focus on the appropriate diagrams and quality checks corresponding to their modeling space. This analysis is performed on each UML diagram, enabling readers to fully comprehend these diagrams, their advantages and limitations, and the way in which they can be used in practical projects for modeling. Name a disadvantage of using Uml: . They seem to believe that every employment of an conceptual design deserves to be called “object-oriented.” This misleading notion recur from cover to cover, short-selling object-orientation and shortchanging the reader. And fails to demonstrate the superiority of UML over ERD for database design. Aiming for a balanced consideration of these alternative techniques, it includes a section “Disadvantages of UML Diagramming” that omits mentioning the absence of a notational convention for representing identity–UML’s most serious disadvantage in this reader’s opinion.The side-by-side UML versus ERD data model comparisons presented throughout the rest of the book show how little real difference there is between the two conventions. These comparisons were nevertheless valuable when the book first appeared and UML was new stuff. Since then UML has so far extended its mind share that today’s reader may focus on UML alone–not because it is superior, but just because it is a standard. Many of the code examples could also be eliminated. They often do no more than illustrate a simple idea or variation more economically explained in text. It is not hard to find long samples of code differing from their predecessors by only a single line Another problem with the code examples is that they are generally separated from the data models whose implementations they illustrate. While reading an example, one must travel several pages back to view the diagram of the subject data structure. Error and ignorance are more commonly encountered than they ought to be in a volume so priced.Why it is a disadvantage:Uml is a multiple-view syntactic Meta model, which means that it defines many different diagrams each one covering a particular modeling perspective of the system by one hand this is an advantage since it allow the designers to specify the aspect they find important for specific purposeWithout imposing a particular development process model .by another hand This may be a disadvantage since the diagrams are interrelated although formally which means that inconsistency can be introduce in the system specification. another related problem lies on the fact that there different diagrams for similar purpose .uml is not formal notation that is it has not well defined sementics.uml is a semi formal language because it has a formal syntax but it semantic is not formal this fact may impose different interpations on the semantics which implies that a diagram may not be equally interpreted by two different designers .
