Lecture 8: Components and Implementation

Question 1

What is an interface?

Answer 1

• Specifies a named set of public features
• Separates the specification of its functionality from its implementation
• Defines a contract that classes and subsystem may realise

Question 2

What should the contract be conformed to?

Answer 2

• operation
• attribute
• association
• constraint
• stereotype
• tagged value
• protocol

Question 3

What is a required interface syntax?

Answer 3

A required interface indicates that a classifier uses the services defined by the interface

Question 4

What is an assembly connector?

Answer 4

You can connect the provided and required interface using an assembly connector

Question 5

What is ports organising interface?

Answer 5

• Specifies the interaction point between a classifier and its environment
• A port is typed by its provided and required interfaces:
- May have a name

Question 6

What is the key to interfaces?

Answer 6

• Interfaces are key to component based development

Question 7

What is a component?

Answer 7

• Defines the requirements for software deployed to hardware
• Represents a part of a system that **encapsulates **the contents whose display is replaceable within its environment

Question 8

What can a component be (2 kinds)

Answer 8

Can be either logical or physical

Question 9

What is a subsystem?

Answer 9

• Acts like a unit of decomposition for larger systems
• Used to decompose larger systems into manageable chunks
• Connected to an interface to create a **system architecture **

Question 10

How do you finding interfaces and ports?

Answer 10

• Look for repeating groups of operations and its usefulness elsewhere
• Possibilities for future expansion
• Cohesive sets provided and required interfaces and organise to named ports
• Look for dependencies between subsystem

Question 11

How do you design interfaces?

Answer 11

• Designing interfaces based on common sets of operation
• Designing interfaces based on common roles
• Designing interfaces based on plug-in features/algorithms
• The Façade pattern can be used to create “seams” in a system

Question 12

What is a physical archietecture?

Answer 12

• Subsystems and interfaces comprise the physical architecture of the model
• Can apply “layering” architectural pattern

Question 13

What are the advantages of using interfaces?

Answer 13

• Defines** contracts** that classes and subsystem may realise
• Programming to its interfaces increases **flexibility and extensibility **
• Programming to interfaces rather to classes reduces dependencies between classes and subsystems

Question 14

What are the disadvantages of using interfaces?

Answer 14

• Can add flexibility but may lead to complexity
• Can make it difficult to understand

Question 15

What’s the implementation purpose?

Answer 15

• Implements the design classes and components
• Converts the design model into executable program

Question 16

Whats a deployment diagram?

Answer 16

• Is an object model that describes the functionality distributed across the physical nodes
• Models the physical and software architecture

Question 17

Describe the physical architecture of deployment diagrams

Answer 17

• Nodes = big boxes that represent the physical hardware
• Artifacts = small box inside the node that represents the physical software file

Question 18

What is an artifact?

Answer 18

• An artefact represents a type of a real-world thing, file

Question 19

What does Manifest mean?

Answer 19

Manifest means to implement a component

Question 20

Whats the relationship between artifacts?

Answer 20

• Can manifest in one or more components
• Can contain other artifacts
• Artifacts deploys nodes
• Artifact instances deploys on node instances