Tutorial 5
IT323 - Software Engineering 2
1

What is component composition? What are
the three different types of composition?
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The process of assembling components to create a system.
Types of composition
 Sequential composition
 Hierarchical composition
 Additive composition
3
What are the two principal component
interfaces?

4

A provides interface
that defines the services provided by that component to other
components.

A requires interface
that defines the services expected by a components when it is
integrated with other components. If these services are not
available, then the provides interface cannot be guaranteed.
5

Consider the two components below: Data collector and Sensor.
The Data collector component requires the services provided by
Sensor component to get the SensorManagement and SensorData.
From the above specification, compose the two components.
Which type of component composition used? Is there any type of
interface incompatibility ?Requires int er face
Provides int er face
addSensor
removeSensor
star tSensor
sensorManagement
Data collector
sensorData
stopSensor
testSensor
initialise
repor t
listAll
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

Type of Composition: Hierarchical composition.
Type of interface incompatibility:
◦ Operation incompleteness.
◦ Operation incompatibility.
sensorManagement
ad dSen so r
remo veSensor
star tSen so r
star t
sensor
stop
g etd ata
Adapter
Data co llector
sensorData
stop Sensor
testSen so r
in itialise
repo r t
listAll
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
In a photo library system, components are used to implement
a system that download images from a digital camera and
stores them in a photograph library. The components are:
Photo Library, Image Manager, and User interface. Each
component provides the following services:
◦ Photo Library:public void addItem (Identifier pid ; Photograph p;
CatalogEntry photodesc) ;
◦ Image Manager:public Photograph retrieve (Identifier pid) ;
◦ User interface:public CatalogEntry catEntry (Identifier pid) ;
Compose the components using the right composition type?
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9

Give 6 examples of general services that
might be implemented in component
model middleware support?
10

Component management.

Transaction management.

Resource management.

Concurrency.

Persistence.

Security.
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
Give examples of changes you might
make to a component to make it more
reusable?
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
Remove application-specific methods

Generalize names

Add methods to provide more coverage

Make exception handling consistent

Add a configuration interface

Integrate required components
13

What are the stages of the CBSE process?
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
Outline system requirements

Identify candidate components

Modify requirements to fit components

Architectural design

Identify candidate components

Compose components
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Thank you 
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