UML

Question 1

What is UML?

Answer 1

Unified Modelling Language, used for specifying, visualising, constructing, and documenting software systems, as well as business and non-software systems.

Question 2

What are UML architectural views?

Answer 2

Logical, physical, development, and process views for visualising different aspects of a system.

Question 3

What are the different levels of detail in UML?

Answer 3

Concept level (highly abstracted) and design level (detailed, code-like).

Question 4

What is the rule for elements in a UML diagram?

Answer 4

7±2 elements per diagram for optimal clarity without excessive complexity.

Question 5

What are the types of inheritance in UML?

Answer 5

Weak inheritance (white triangle) and strong inheritance (black triangle).

Question 6

How many diagrams does UML 2.x include?

Answer 6

Nine diagrams, including four new ones and some syntax changes.

Question 7

What is a UML use case diagram?

Answer 7

A diagram showing system functions provided to classes of users and their interactions.

Question 8

How does UML show system interfaces?

Answer 8

Using stereotypes with chevrons («System») and arrows for one-way communication.

Question 9

What is a UML class diagram?

Answer 9

The core diagram of UML, showing logical structure and connections between system components.

Question 10

What is a UML object diagram?

Answer 10

A class diagram for a single instance, with instance names underlined and annotated.

Question 11

What is a UML collaboration (communication) diagram?

Answer 11

Object diagrams with message arrows showing sequences and relationships between collaborating objects.

Question 12

What is a UML sequence diagram?

Answer 12

Shows the sequence of interactions over time, using activation bars and vertical arrangements.

Question 13

What are UML transition diagrams?

Answer 13

Activity or state diagrams showing the flow of activities or tasks, with decision points and synchronisation bars.

Question 14

What are UML activity diagrams?

Answer 14

State diagrams with synchronisation bars, illustrating parallel and sequential tasks.

Question 15

What is a UML component diagram?

Answer 15

Shows physical software structure, components, interfaces, and dependencies between them.

Question 16

What is a UML deployment diagram?

Answer 16

Illustrates the physical architecture of hardware and software communication in a system.

Question 17

What is a UML implementation diagram?

Answer 17

Shows where and how components will be implemented and their interdependencies across nodes.

Question 18

What are UML extensions?

Answer 18

Stereotypes, symbols, and customisations using chevrons, colours, or pictures, making UML extensible.

Question 19

How does UML represent component dependencies?

Answer 19

With a dashed line and arrowhead (line and cup in UML 2.x).

Question 20

What is the purpose of UML interfaces?

Answer 20

Defines publicly accessible methods for components to call on other components or their internal classes.

Question 21

How are UML use case diagrams related to class diagrams?

Answer 21

Use case diagrams identify the system’s functionality, which can be used to derive the classes and their responsibilities in class diagrams.

Question 22

How are class diagrams related to object diagrams?

Answer 22

Class diagrams show the blueprint of the system’s structure, while object diagrams represent specific instances of those classes at a given time.

Question 23

How are sequence diagrams related to collaboration diagrams?

Answer 23

Both show object interactions; sequence diagrams focus on the time-ordered sequence of messages, while collaboration diagrams emphasise relationships between objects.

Question 24

How are activity diagrams related to state diagrams?

Answer 24

Activity diagrams model workflows or task sequences, while state diagrams focus on an object’s state transitions. Both use similar notation for events and decisions.

Question 25

How are component diagrams related to deployment diagrams?

Answer 25

Component diagrams show software components and their relationships, while deployment diagrams map these components onto physical hardware nodes.

Question 26

How are use case diagrams related to sequence diagrams?

Answer 26

Use case diagrams describe system functionality, and sequence diagrams provide detailed interactions for implementing specific use cases.

Question 27

How are state diagrams related to sequence diagrams?

Answer 27

State diagrams describe the life cycle of an object, while sequence diagrams detail how objects interact within those states.

Question 28

How are activity diagrams related to use case diagrams?

Answer 28

Activity diagrams elaborate the flow of actions within a use case, showing decision points and parallel activities.

Question 29

How are logical and physical views connected in UML?

Answer 29

Logical diagrams (e.g., class diagrams) define the software’s abstract structure, while physical diagrams (e.g., deployment diagrams) map this structure onto actual hardware.

Question 30

How are component diagrams related to class diagrams?

Answer 30

Component diagrams encapsulate sets of related classes, showing their dependencies and interfaces.