General_UML

Question 1

Name 5 diagram types in UML

Answer 1

Use Case Diagram
Class Diagram
Activity Diagram
Sequence Diagram
Statechart Diagram

Question 2

What does a use case diagram do?

Answer 2

Describes the functionality of a system, from user’s pov (functional)

Question 3

What does a class diagram do?

Answer 3

Describes a system in terms of objects, attributes, operations, relations (Structural)

Question 4

What are the three parts of a Class Diagram and what are their naming conventions?

Answer 4

Class Name: singular noun; camel uppercase
Attributes: lower camelcase
Methods: lower camelcase

Question 5

How do we control who can access the attributes and methods of a class?

Answer 5

\+ public: can be used by code outside the object
-  private: can only be accessed within the defined class
# protected: accessible from defining and child classes
~  package: available within its enclosing package

Question 6

Name the different kinds of relationships that express the relations and dependencies between the objects (+ annotation)

Answer 6

Generalization: “is a”; child-parent; line with open arrow head
Association: “interaction”; full line
Aggregation: “has a”; line with hollow diamond at owner’s end (redundant?)
Composition: “part of”; ownership; when owner dies contained objects die too
Dependency: “references”; changes in one class may cause changes in the other; dashed line with arrow at dependency
Realization: “implements behavior”; class implements the behavior specified by another element: dashed line with open arrow at implementor’s end

Question 7

What are possible nodes in an Activity Diagram? + explain + annotation

Answer 7

Decision node: one inbound flow, two or more outbound; filled diamond; add guards between [] near outbound flows
Merge node: two or more inbound flows; one outbound; hollow diamond

Question 8

How do you represent concurrent, parallel behavior in an Activity Diagram?

Answer 8

Fork: one inbound, two or more outbound; need to be synchronized; thick line
Join: represents synchronization after fork; two or more incoming, one outbound; thick line

Question 9

What are the elements of a Statechart Diagram

Answer 9

State: possible conditions; rounded rectangles
Transition: arrow, with trigger event as annotation
Event: event that triggers the transition

Question 10

What are the preliminary steps for Object-Oriented Design?

Answer 10

Gather requirements
Describe system pov user
     Use cases
     User stories
Identify classes
Create diagrams