UML(Unified Modeling Language) Tutorial


1. Explain Deployement Diagram?

  • Used for describing the hardware components where software components are deployed
  • Component diagrams are used to describe the components and deployement diagram shows how they are deployed in hardware
  • Deployement diagrams consist of nodes
  • Nodes are nothing but physical hardwares used to deploy the application
  • Describe the physical components and their distribution and association

2. Explain Use Case diagram?

  • Capture the dynamic aspects of a system
  • Used to get the requirements of a system including internal and external influences
  • These requirements are mostly design requirements
  • When a system is analyzed to gather its functionalities use cases are prepared and actors are identified.
  • Uses cases are nothing but the system functionalities written in an organized manner.

3. Explain Interaction Diagram?

  • Describe some types of interactions amoung the different elements in the model.
  • This interaction is part of dynamic behaviour of the system
  • Sequence diagram and collaboration diagrams are used in UML for this purpose
  • Sequence Diagram – Emphasizes on time sequences of messages
  • Collaboration Diagram – Emphasis on the structural organization of objects that send and receive messages

So the following things are to identified clearly before drawing the interaction diagram:

  • Objects taking part in the interaction.
  • Message flows among the objects.
  • The sequence in which the messages are flowing.
  • Object organization.
  • The message flow is nothing but a method call of an object.
  • In collaboration diagram the method call sequence is indicated by some numbering technique
  • The difference is that the sequence diagram does not describe the object organization where as the collaboration diagram shows the object organization.
  • If the time sequence is important then sequence diagram is used and if organization is required then collaboration diagram is used.

4. Explain StateChart diagram?

  • Describes different states of a component(Object) in a system
  • These states are controlled by internal or external events
  • Used to model dynamic nature of the system

Before drawing a Statechart diagram we must have clarified the following points:

  • Identify important objects to be analyzed.
  • Identify the states.
  • Identify the events.

5. Explain activity diagram?

  • Basically a flow chart to represent the flow form one activity to another activity
  • The activity can be represented as an operation of the system
  • This flow can be sequential, branched or concurrent
  • Other diagrams are used to show the message flow from one object to another object
  • But activity diagram used to show the control flow from one activity to another activity
  • Activity is a particular operation of the system

So before drawing an activity diagram we should identify the following elements:

  • Activities
  • Association
  • Conditions
  • Constraints