Chapter 4

Question 1

Difference between component type and instance?

Answer 1

With component type, we define the component but when we want to use the component in a context, we instantiate it (component instance)

Question 2

Difference between component type diagram and composite structure diagram?

Answer 2

Component type diagram is a UML class diagram we use to define the actual decomposition of component by defining the types i.e the specification of the containees while the composite structure diagram defines the actual realisation by instantiating the containees and connecting them with the help of connectors.

Question 3

What do you understand by component repository?

Answer 3

It is like a complex library containing all reusable component types.

Question 4

How is packages used in component repository?

Answer 4

Package is used to group several component types which belong together from reuse point of view without defining any further relationship between these components.

Question 5

Explain the use of ports in component structure diagrams?

Answer 5

To model the interconnection of components, ports are used to define the interface of components. Connectors define the actual connection of components by creating the link between the respective ports of the components.

Question 6

Three types of interaction diagrams introduced in the course are?

Answer 6

• Sequence diagrams
• Communication diagrams ( also called Collaboration diagrams), and
• Timing diagrams

Question 7

Highlight the two possible ways to realiize the specification of a component

Answer 7

1. Direct implementation if the behaviour specified in the component for realizing the specification is simple enough
2. Decomposition to sub-components

Question 8

Use of ports in component structure diagram?

Answer 8

ports are used to model the interconnection of components

Question 9

What is connector?

Answer 9

Connector defines the actual connection of components by creating the link between the respective ports of the components.

Question 10

Decomposition models

Answer 10

define the containee components and the connections between them.

Question 11

What are the three types of interaction diagrams used for modelling connections?

Answer 11

1. Sequence diagrams
2. Communication diagrams / Collaboration diagrams
3. Timing diagrams

Question 12

When to use sequence diagram and communication diagram

Answer 12

Use sequence diagram when you want to indicate the sequence of events and communication diagram when you want to underline the structure of the interaction.

Timing diagram focuses on the changes of values and states of the participants over time.