Analysis Model in Software Engineering

  • Analysis model operates as a link between the 'system description' and the 'design model'.
  • In the analysis model, information, functions and the behaviour of the system is defined and these are translated into the architecture, interface and component level design in the 'design modeling'.

Elements of the analysis model

1. Scenario based element
  • This type of element represents the system user point of view.
  • Scenario based elements are use case diagram, user stories.
2. Class based elements
  • The object of this type of element manipulated by the system.
  • It defines the object,attributes and relationship.
  • The collaboration is occurring between the classes.
  • Class based elements are the class diagram, collaboration diagram.
3. Behavioral elements
  • Behavioral elements represent state of the system and how it is changed by the external events.
  • The behavioral elements are sequenced diagram, state diagram.
4. Flow oriented elements
  • An information flows through a computer-based system it gets transformed.
  • It shows how the data objects are transformed while they flow between the various system functions.
  • The flow elements are data flow diagram, control flow diagram.

elements analysis model

Analysis Rules of Thumb

The rules of thumb that must be followed while creating the analysis model.

The rules are as follows:
  • The model focuses on the requirements in the business domain. The level of abstraction must be high i.e there is no need to give details.
  • Every element in the model helps in understanding the software requirement and focus on the information, function and behaviour of the system.
  • The consideration of infrastructure and nonfunctional model  delayed in the design.
    For example, the database is required for a system, but the classes, functions and behavior of the database are not initially required. If these are initially considered then there is a delay in the designing.
  • Throughout the system minimum coupling is required. The interconnections between the modules is known as 'coupling'.
  • The analysis model gives value to all the people related to model.
  • The model should be simple as possible. Because simple model always helps in easy understanding of the requirement.

Concepts of data modeling

  • Analysis modeling starts with the data modeling.
  • The software engineer defines all the data object that proceeds within the system and the relationship between data objects are identified.
Data objects
  • The data object is the representation of composite information.
  • The composite information means an object has a number of different properties or attribute.
    For example, Height is a single value so it is not a valid data object, but dimensions contain the height, the width and depth these are defined as an object.
Data Attributes
Each of the data object has a set of attributes.

Data object has the following characteristics:
  • Name an instance of the data object.
  • Describe the instance.
  • Make reference to another instance in another table.
Relationship
Relationship shows the relationship between data objects and how they are related to each other.

Cardinality
Cardinality state the number of events of one object related to the number of events of another object.

The cardinality expressed as:

One to one (1:1)
One event of an object is related to one event of another object.
For example, one employee has only one ID.

One to many (1:N)
One event of an object is related to many events.
For example, One collage has many departments.

Many to many(M:N)
Many events of one object are related to many events of another object.
For example, many customer place order for many products.

Modality
  • If an event relationship is an optional then the modality of relationship is zero.
  • If an event of relationship is compulsory then modality of relationship is one.