4. design concepts

Question 1

s/w design process

Answer 1

Design fields of software development deals with the transforming customers requirements described in srs document into Implementable form using programming language
lvls or phases of design:
1. interface design
2. architectural design
3. detailed design

Interface design
Description of interaction between system and its environment
- This face brisket at high level abstraction
- Confused attention is focused on the dialogue between the target system and the users, devices and other systems
- The design problem statement is produced during the problem analysis
it should contain:
1) Precise description of events in the environment and agents to which systems must respond
2) Precise description of events that system must produce
3) The formats of data coming into and going out of the system

architectural design:
Specification of major components of the system, their responsibilities, properties, relationship and interactions between them.

detailed design
Specification of internal elements of all major system components, their properties, their relationships, processing and their algorithms and the data structures
1. Dividing major system components into programme units
2. Allocation of functional responsibility to units
3. User interfaces
4. Unit States N state changes
5. Algorithms and data structures

Question 2

Function oriented diesel

Answer 2

Design process of a surface steps often have two levels
1st- Deciding on which modules are required for the system based on Srs
2nd - How the model should be interconnected

Function oriented design is an approach to software design, where design is divided into a set of interacting units when each unit has clearly defined function

generic procedure
It starts with high level description of what software programme does
- thenit refines each part of the description by specifying them in greater detail
- These lead to top down structure

Function oriented design strategies
1) Data flow diagram(DFD)
It Maps out the data of any process in the flow chart diagram
- It uses symbols like rip angle circles and diabetes, press short textile labels to show data inputs, output storage points in their routes between each destination

2) data dictionary
- Repository to store information about all data items defined in Dfds
- It includes name of the item, Alias, Description \purpose Related data items common range of data items, datastructure definition
3) structure charts
Hierarchical representation Of system which partitions the system into black boxes
4) pseudo codes
System description in short English like phrases describing the factual it uses keywords and intentation
- Used in replacement of flowcharts it decreases amount of documentation

Question 3

oo design

Answer 3

System is viewed as the collection of objects
And each object handles its state data
- Tasks defined for one purpose cannot refer change data of other objs
- Similar objects create a classes may inherit features from super class
terms related:
1. Objects
System is named as collection of objects or entities
2. clses
Similar objects form classes
3. messages
Objects communicate by message passing
4. abstrcation
Complexity is handled using abstraction
5. encapulation
Heat and operations are linked into single units
6. inheritence
Similar classes can stack up in hierarchical manner where the lower subclasses can import in moment and views allowed variables and functions
7. polymorphism
Provides a mechanism and methods Performing similar task but vary in arguments can be assigned same name.

Question 4

Verification
validation

Answer 4

verification
1. Also known as static testing
2. Process of checking that software achieves its goal without any bugs.
2. It is a process to ensure whether the product that is being developed is right or not
3. It also ensures that whether the software is fulfilling customer requirement or not

activities:
1) Inspections
2) reviews
3) walkthroughs
4) desk-checking

validation
- Also called as dynamic testing
Process of checking whether the software product is up to the mark. That is, the product has high level requirements or not
- cheques what we are developing is the right product
1. Black box Testing
2. white box testing
3. Unit testing
4. integration testing

Verification is followed by validation

Question 5

s/w metrics

Answer 5

measure Of software characteristics, which are measurable or countable.
- Software metrics are valuable for many reasons, including measuring software performance, planning, work items measuring productivity and other uses
- Software metrics are similar to poor functions of management, planning, organisation, control or improvement.

classification:
1. Product metrics
Measure of various characteristics of the software product . the 2 imp:
i. Size and complexity of software
ii. quality and reliability of software.
2. process metrics
These are measures of various characteristics of software development process.
- They are used to measure characteristics of methods, techniques and tools that are used for developing a software

types:
1. internal metrics
Metrics that are used to measure properties that are viewed to be greater importance to software developer
eg:
Lines of code (LOC)
2. ext metrics
Matrix used for measuring properties That are viewed to be greater importance to the user.
eg: Portability, reliability, functionality, etc.
3. hybrid metrics
Metrics that combine product process and resource metrics
eg: cost
4. project metrics
Metrics that are used to check the projects progress by project manager
- Data from past projects are used to collect various metrics like time and cost. These estimates are used as a base of new software

adv:
read://https_www.javatpoint.com/?url=https%3A%2F%2Fwww.javatpoint.com%2Fsoftware-engineering-software-metrics

Question 6

coding

Answer 6

Process of converting design of a system into computer language format that is source code
- Coding is done by the coder or programmer who are completely independent people than the designer

goals:
- To translate the design of system into computer language format
- To reduce the cost of later phases
- Making the programme more readable

characteristics:
1. Readability
2. portability
3. error checking
4. generality
5. braverty
6. cost
7. quick translation
8. efficiency
9. modularity
10. widely available.

coding standards:
1. Indentation
2. inline comments
3. use of global
4. structured programming
5. naming conventions
6. errors and exception handling

Coding guidelines:
1. line length (it is good practise to keep the length of the source code lines 80 characters or below it)
2. spacing (Yusuf spaces within line of code can improve readability)
3. Lines of code Lines of court should not increase more than ten sources lines
4. inline comments Promotes readability
5. comments As a thumb rule there must be one comment lying on average of three source lines
6. Do not use Go to statements
7. Error messages
Essential aspect of computer programming It helps in handling errors

Question 7

Managing evolving code in the coding

Answer 7

1. Version control
2. refactoring code
3. review
4. quality code
5. clean code

Question 8

unit testing

Answer 8

• Software testing that focuses on individual units of components of software system
• The purpose of unit testing is to validate that each unit of software works as intended and meets the requirements
• It is done Buy developers and performed before The code is integrated and tested as whole system(Before integration testing, system testing, acceptance testing)
• Unit tests are automated and run each time the court changed to ensure that new courts doesn’t break existing functionality

types of testing:
1. Manual
2. automated

techniques:
1) black box testing
This technique is used in converting unit tests for input user interface and Output parts.
2) white box testing
Used in testing the functional behaviour of the system by giving the input and checking the functionality output,
3) Grey box testing
Used in executing relevant test cases. Test methods and test functions and analysing the code performance for the modules

tools:
1. Jtest
2. Junit
3. Nunit
4. EMMA
5. PHPUnit

Question 9

code inspection

Answer 9

As every software application or product goes through Hdlc, where every face is very important and needs to followed accordingly to develop quality Air product
- code inspection is such an important element
- Software development team develops and cheques the errors, which is called as code verification
- Generally, there are two types of code verification techniques:
1. dynamic technique
Performed by executing some test data and outputs of the input are monitored to find errors
2. static
Performed by executing programme conceptually without any data

code inspection
Code inspection is a type of static testing that aims to **review the software code and examine for any errors **
- It helps reduce the ratio of defect multiplication and avoids later stage error detection by simplifying all the error detection processes
working:
1) Moderator, reader, recorder and author are the key members of the inspection team
2) Related documents are provided to inspection team who then plan inspection meeting and coordinate with inspection team members.
3) If the inspection team is not aware of the project in order will provide an overview of the project and Cope to inspection team members
4) 10 inspection team performs code inspection by following some inspection checklist.
5) After completion of code inspection code, a meeting is conducted with all team members and analyse the reviewed code

adv:
1. cheques for any error that are present in software code
2. Identifies any required process improvement
3. cheques weather coding standards are formed or not.
4. It documents the defects in the code