What is UML?

UML or Unified Modeling Language is a modeling standard in the field of object oriented software systems. It has been standardized by OMG(Object Management Group) after being developed by Rational Corp(Booch Group). UML is a modeling language which puts together several diagrammatic views which can be used for any stage of the software development life cycle. UML was designed basically to provide a common platform for all the stakeholders in a project starting from the end users, analysts, designer, developers etc who are vital to the success of the project. So, in a way it cut down the miscommunication of the requirements and the display of the design in one common language which is understandable by everyone concerned.

 But UML provides you with the syntax of the diagrams and views but does not actually give you the context in which it has to be used. Its up to the designer or analyst to find the best fit for the particular UML Diagram. The best thing about UML is that its code independent. As long as its object oriented programming, UML diagrams can fit into it.

 UML provides us with the different diagram types which can be used in the design of an object oriented software systems. They are broadly classified into Structural Modeling diagrams(which depict the static structure of the system) and Behavioral Modeling diagrams(which depict the behavior and transactional movements of the system). Some of the most commonly used UML diagrams are:

a) Use Case Diagrams – is a high level diagram depicting the system boundary and the interaction between the actors(users/external interfaces) and the system

b) Interaction Diagrams – Shows how the different objects of the system interact with each other

c) Activity Diagrams – shows the business process flow and makes use of the use cases similar to data flow diagrams

d) Class Diagrams – depicts the properties and behaviors of the classes to be used in the system. Objects are instances of Classes and an Object diagram depicts the objects in a similar manner to the class diagram.

e) Sequence Diagrams – are used to display the orderly sequence of message transfer between entities of the system

f) Component Diagrams – shows the component types and their dependencies in the architecture of the system as a whole

g) Deployment Diagrams – shows the physical architecture and the deployment components.

Fig A – UML Diagrams

Out of these UML diagrams which are as shown in Fig A , Business Analysts worldwide would mostly use the Use Case Diagram, Activity Diagram and sometimes, Sequence and Class Diagrams. Apart from these , the majority of the rest of the UML diagrams are designed by the solution architect or designers. It is not essential that for any project all of the UML diagrams will have to be made. The UML diagrams are vital for a business analyst as they help him in getting the requirements validated and assessed. UML diagrams also add clarity to the functional specification documentation and hence are widely used by the Business Analysts to corroborate their requirement elicitation.