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  • Software Requirement: case study

    Objectives

    Use case modelling
    Activity modelling
    Class modelling
    Database design
  • Stakeholders

    Any person or organisation who is affected by the system in some way and so who has a legitimate interest. Any one who is affected by the system or who has influence on system development or use the system is a stakeholder.

    For example:
    Customers (e.g. End users and system owner(s), system managers)
    Developers (requirement/system analyst, 3D designers, programmers, project manager etc.)
    External stakeholders

    What are the main factors which cause software failure?

    Customer as stakeholder:
    Didn’t meet the customer’s needs or misunderstood/ not fully captured their requirements.
    Change requirements too often
    Customers are lack of commitment to the project
    Customers don’t understand the terminology,
    Lack of communication with developers
    Customers have unrealistic/high expectation to the project.
    The system is no longer benefit to the business or customers.

    Scenario: Online Furniture Purchase

    The following scenario will be used to discuss the Use Case Modelling Approach to Requirements Capture.

    Requirements:

    1. Mr John Smith would like to purchase 3-seater sofas over Internet using the manufacturer’s web site which is called furniture4u.co.uk. This is family run business and provide great costumer services.
    2. Computers classified into servers, desktops and portables e.g. tablet and mobile phone device.
    3. Customer can select colour, fibre and style and delivery date, the system will able to the calculate total price.
    4. To place order, the customer must join the membership and fill out the personal information, shipment and payment information.
    5. New member will be given his/her user name and password
    6. The system sends a confirmation e-mail message to the customer with details of the order.
    7. Customer can check the order status, online and shipping details at any time when they login the system. The system should also allow the customer to cancel order or amend order. The system should able to process refund.
    8. Additionally, the system should able to
    verify the customer’s credentials and provide payment methods such as paypal, credit card or debit card payments.
    request the ordered from the factory,
    print an invoice and also send an invoice by email, to the customer, and
    request the factory to ship the sofas to the customer.
    9. This company uses shipping.com to shipping their furniture to their company. (Outsourcing)
  • How to identify actors?

    Actor represents a role that interacts with the system. Such as human e.g. end users, system managers; time e.g. can trigger event: automatic send an ordering confirmation email to customer. ;hardware device e.g. printer, data projector etc.

    Tip:

    1. look all the nouns in your scenario e.g. customer, salesman etc.
    2. Actor names should clearly indicate the actor’s job role. E.g. if John is a student as a actor. You should use student as your actor’s name rather than John because John is not able to represent all the students. That is why we need to name the actor as actor’s role.

    Identify – actors

    Consider the following requirements:
    The customer may choose to order a sofa online or
    may through online contact us function to make an request that the salesman contact him/her to explain order details, negotiate the price, etc. before the order is actually placed.
    The factory Amin obtains the invoice from the
    salesman and pass shipping detail to shipping.com to ships the sofa(s) to the customer.
    So the potential actors are : Customer, Salesman, factory and shipping company

    What is use-case modelling?

    A use-case model describes a system’s functional requirements in terms of use cases.
    Links and meets to stakeholders needs to software requirements
    Defines clear boundaries of a system
    Captures and communicates the desired behaviour of the system
    Identifies who or what interacts with the system (actors)
    Validates/verifies requirements
    It is very powerful planning instrument, it is generally used in all phases of the development cycle by all software development team members.
    A use-case model consists of both diagrams and text.
    The diagrams give a visual overview of the system.
    The text gives descriptions of the actors and the use case
    Use cases only deal with Functional requirements

    How to create a use-case model

    1. Identify actors and use cases in scenario
    Define each actor by writing a brief description that includes the actor’s responsibility and what the actor needs from the system for.
    2. Write the use cases
    Outline all use cases
    Prioritize the use-case flows
    Detail the flows in order of priority
    When actors and use cases have been identified, each use case is described in details which show how the system interacts with the actors and what the system does in each individual case/
  • Define use case

    A use case describes a set of possible executions of the system.
    A use case defines a sequence of actions performed by a system that produces an observable result of value to an actor.

    How to identify use cases

    Use case represents something of value that the system does for its actors.

    A use care describes:
    The system, its environment and the relationship between them.
    How things outside the system interact with the system
    The desired behaviour for the system

    Use Case Symbol

    Tip:

    Use case begins with a verb
    Indicate the value or goal of the actor
    Look all the verbs in your scenario e.g. order, request, print etc.

    Identify use cases

    Consider the following requirements:
    The customer may choose to order sofa(s) online or
    may through online contact us function to make an request that the salesman contact him/her to explain order details, negotiate the price, etc. before the order is actually placed.
    The factory Admin obtains the invoice from the salesman and ships the sofa(s) to the customer.
    Order sofa(s)
    Request Print Invoice
    Request Salesman Contact
  • useCase Diagram

    Communicates-Associations in use-case diagram

    A channel of communication between an actor and a use case.
    Relationships between actors and used cases are called communicates-associations.
    A line is used to represent a relationship between actors and use cases.
    An arrowhead is used to indicate who initiated the interaction
    No arrowhead indicates either end can initiate each interaction.

    Example of Communicates-Associations

    Actor: customer always initiates communication with the system.

    The system may respond to messages from actor: customer but can never send an unsolicited message to customer., the system always initiated communication with Actor: shipping company.

    Actor: shipping company may respond to message to the system, but can never send an unsolicited message to the system. For the actor: salesman or the system may initiate the dialog.

    Example of Communicates-Associations
  • Use case Form

    Use Case Name Place order
    Description This use case allows a customer to purchase furniture online. This includes proving shipping detail and invoice address and payment details.
    Actors Primary: customer; salesman
    Priority High
    Risk High
    Assumptions One or more sofas have been added to the system. One or more sofa types
    Pre-conditions Customer points Internet browser to the furniture’s order entry website. The page displays the details of choices colours, fibres and styles together with total costs.
    Extension Points Payment
    Extends None
    Trigger A customer wishes to place order via salesman
    Main Flow of Events 1. Salesman enters the required sofa type, colour and fibre. [A1] [A2]
    2. System checks if a sofa of that style is available. [A3]
    3. System notifies that a sofa is available and calculate total price.
    4. Customer accepts sofa offered. [A5]
    5. Extension Point (payment). [A6]
    6. System records order.
    7. System displays order number and automatic send out confirmation order to customer’s email address.
    Alternative flow Of Events A1. The colour/fibre is not available. Display message and return to step 1.
    A2. Sofa style invalid. Display message. Return to step 1.
    A3. Sofa is out of product line for the required item. System changes sofa style for search. Return to step 2. [A4]
    A4. No other Sofa style customer like it. Display message. Return to step 1.
    A5. Sofa offer is declined. End of use case.
    A6. Payment rejected. Display message. Return to step 5. 
    At any time use case can be cancelled.
    Post-condition New sofa style added. Colour/fibre available is reduced by the discount/on sale period.
    Payment details are recorded. If the use case was successful, the purchase order is recorded in the system’s database. Otherwise, the system’s state is unchanged.
    Non-Functional Requirements Successful use case must take no longer than 2 minutes to complete. Search for available sofas must take no longer than 30 seconds. This use case must be available 24/7. This use case up time must be 99.9% during each 24 hour period.
    Can’t accept order without check the stock system.
    Issues Make use the online payment is secured.
  • What is an activity diagram?

    Activity diagrams/ flow charts are useful tool which it can be use to describe a use case too.
    Activity diagrams use to describe complex flows of events.
    Each event is a state of doing something. For this reason, the execution events for an activity are called action states.
    The flow of control from on action state to next is called a flow.
    If a use-case document has been completed, then activities and action states can be discovered from he description of the main and alternative flows.

    Activity diagram: notations

    An activity diagram shows flows between actions.
    The diagram has an initial action state and one or more final action states.
    A solid filled circle represents the initial state. The final state is shown using a two circles symbol. In side the circle is fully filled. E.g.

    Activity Diagram Notation Diagram

    Diamond box shows that branch condition. The exit from a branch condition is controlled by an event (such as yes, no) or by a guard condition e.g. excellent, good/poor)

    Activity Diagram Notation Diagram

    Rectangle box shows the use cases. The use cases are beginning with verb e.g. display transaction detail, confirm transaction, and refuse transaction etc.

    Activity Diagram Notation Diagram
  • Activity Diagram Process Orders Sofa's

    Activity diagram – actions

    Actions : Process Order sofa(s)

    1. Get Purchase Store Order:
    The Customer searches and then chooses the Purchase function to submit his/her order to the funiture4u.com website.

    2. Store Order:
    The system assigns a unique order number to the customer and links to the customer account number to the purchase order.
    The order system will store the order’s details in the database.

    3. Email the customer his/her ordering details
    The system automatic send e-mails to the Customer the Ordering Details which include the unique order number and the customer ID, total cost etc. as the confirmation of the order’s acceptance.

    P.S. If the customer didn’t find what he/she looking for or the item is not available, the system should give the customer another choice or to close the search.

  • Class attributes

    The structure of a class is defined by its attributes. Without attributes, we can’t store the data in the class. Finding meaningful and useful attributes are important. In practice, the main attributes are usually allocated to a class immediately after the class has been added to the model.

    Tips for finding attributes

    Most attributes can be found from user requirements and from the domain knowledge.
    Step1 : work on defining identifying attributes for each class.
    Step 2: one ore more attributes in a class that have unique values across all instances of the class. E.g. orderID. It is called primary key or class key. Ideally, a primary key should consist of one attribute.

    What is class diagram?

    Following the approach taken in finding actors and use cases, activity diagram, now we can construct a class diagram from the analysis of functional requirements.
    Entity classes define the functional requirements in software system.
    In class diagram, it includes class name, attributes and relationship between classes and operations/methods.

    Tips for finding classes

    Finding classes is an interactive tasks.
    Step 1: list the initial list of possible candidate classes (check the actors, sometimes actors can be your classes)
    Step 2: Is the concept a container for data?
    Step 3: does it have separate attributes that will take on different values?
    Step 4: would it have many instance objects?
    Step 5: Is it in the scope of the application domain?

    Class Diagram

    Associations between classes establish pathways for easy object collaboration.

    Class Diagram Diagram

    Graphically, a class is represented as a rectangle with three compartments. From the top to the bottom compartments which are class name, class attributes and class operations/methods.
  • Class diagram-identify attributes

    Customer class’s attributes:
    cId: String
    cName: String
    cAddress: String
    cPhoneNumber: String
    cEmail:String
    Etc…

    order class’s attributes:
    orderID: String
    totalCost: float
    orderDate: Date
    shippingStatus: String
    orderPaid: Boolean
    Etc…

    furniture class’s attributes:
    furnitureID: String
    furnitureName: String
    furnitureDescription:String
    cost: float
    colour: String
    Fibre: String
    Style: String
    Etc…

    Orderlist class’s attributes:
    orderListID: String
    orderListName: String
    cost: float
    itemName: String
    itenId: String
    itemDescription: String
    cId: String
    Etc…
  • Associations-relationship between classes

    Associations between classes establish pathways for easy object collaboration.

    Class Diagram Diagram

    Graphically, a class is represented as a rectangle with three compartments. From the top to the bottom compartments which are class name, class attributes and class operations/methods.

    Class modelling-aggregations

    An aggregation is a whole-part relationship between a class representing an assembly of components (super/Parent class) and the classes representing he components (sub/child class).

    A super class contains a sub class.
    For example:

    Class-modelling-aggregations diagram

    Inheritance

    A child class inherits from one parent class.
    Many child classes inherits from one parent class.

    Inheritence Diagram
  • Class Diagram

    Order Sofa

    Class Diagram Order Sofa
  • Sequence Diagram

    Only shows the classes extended with operations.
    Sequence diagram = for action "Display Current Customisation Sofa" (online shopping)

    Sequence Diagram Order Sofa
  • Computer architecture

    Computer Architecture Diagram

    “An architectural model for distributed systems where the system functionality is offered as set of services provided by a server. There ae accessed by client computers that make use of the services. Variants of this approach, such as three-tier client-server architectures, use multiple servers.” (Sommerville, 2011, pp.736)

    Components

    A set of standards for component implementation, documentation and deployment. These cover the specific interfaces that may be provided by a component, component naming, component interoperation, and component composition. Component models provide the basis for middleware to support executing components.

    Components Diagram

    Component is a deployable, independent unit of software that is completely defined and accessed through a set of interfaces.
  • Glossary

    ACDEFGILMOPRSUV


    A

    abstract class

    A class that can be used only as a superclass of some other class; no objects of an abstract class may be created except as instances of a subclass.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.615

    Activity diagram

    Activity diagrams/ flow charts are useful tool which it can be use to describe a use case too.

    Data source: lecture notes

    Actor

    Actor represents a role that interacts with the system.

    Data source: lecture notes

    actor role

    A named end of an association to indicate its purpose

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.618

    aggregation

    A property of an association representing a whole-part relationship and (usually) life-time containment.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.615

    association

    A description of a related set of links between objects of two classes.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.615

    attribute

    A named characteristic or property that is the same for all instances of a class. This information is usually stored in the class definition.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.615

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    C

    class

    In the UML , "The descriptor of a set of objects that share the same attributes, operations, methods, relationships, and behaviour. May be used to represent software or conception elements.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.615

    class diagram

    A UML diagram types that shows the object classes in a system and their relationships. Entity classes define the functional requirements in software system.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.759

    Client-Server architecture

    An architectural model for distributed systems where the system functionality is offered as set of services provided by a server. There ae accessed by client computers that make use of the services. Variants of this approach, such as three-tier client-server architectures, use multiple servers.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.760

    collaboration

    Two or more objects that participate in a client/server relationship in order to provide a service.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.615

    communicates-associations

    Relationships between actors and used cases are called communicates-associations.

    Data source: Lecture notes

    component

    A deployable, independent unit of software that is completely defined and accessed through a set of interfaces.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.760

    component model

    A set of standards for component implementation, documentation and deployment. These cover the specific interfaces that may be provided by a component, component naming, component interoperation, and component composition. Component models provide the basis for middleware to support executing components.

    Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.760

    composition

    The definition of a class in which each instance is comprised of other objects.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.616

    concept

    category of ideas or things. It used to designate real-world things rather than software entities. A concept's intension is a description of its attributes, operations and semantics. A concept's extension is the set of instances or example objects that are members of the concept. Often defined as a synonym for domain class.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.616

    conceptual design

    The development of a high-level vision of a complex system and a description of its essential capabilities. Designed to be understood by people who are not system engineers.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.761

    concrete class

    A class that can have instances

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.616

    constraint

    A restriction or condition on an element.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.616

    coupling

    A dependency between elements (such as classes, packages, subsystems), typically resulting from collaboration between the elements to provides a service.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.616

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    D

    design

    A process that uses the products of analysis to produce a specification for implementation details of some element, such as an object or subsystem. All interaction with an object is through a public interface of operations.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.616

    domain

    A formal boundary that defines a particular subject or area of interest.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.616

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    E

    end user

    That stakeholder group which uses an information system to conduct work

    Data source: Beynon-Davies p, 2002 "Information systems: An introduction to informatics in organisations" , 1st Edition, Palgrave. pp.564

    event

    A noteworthy occurrence

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.616

    Experiments

    designed in terms of hypothesised relationships between independent variables (Those presumed to cause certain phenomena) and dependent variables (those presumed to indicate the presence of certain effects). To study these relationships closely all other variation in the environment has to be controlled.

    Data source: Beynon-Davies p, 2002 "Information systems: An introduction to informatics in organisations" , 1st Edition, Palgrave. pp.564

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    F

    Framework

    A set of collaborating abstract and concrete classes that may be used as a template to solve a related family of problems. It is usually extended via subclassing for application specific behaviour.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.616

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    G

    generalisation

    The activity of identifying commonality among concepts and defining a superclass (general concept), and subclass (specialised concept) relationships. IT is a way to construct taxonomic classifications among concepts which are then illustrated in class hierarchies. Conceptural subclasses conform to conceptual superclasses in terms of intension and extension.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.616

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    I

    inheritance

    A feature of object-oriented programming languages by which classes may be specialised from more general superclasses. Attributes and method definitions from superclasses are automatically acquired by the subclass.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.617

    interface

    A set of signatures of public operations

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.617

    interview

    The research technique is frequently used as a means of gaining an in-depth appreciation of some phenomena. Interviews essentially involve either a structured or unstructured discussion with some person(s) on a certain topic.

    Data source: Beynon-Davies p, 2002 "Information systems: An introduction to informatics in organisations" , 1st Edition, Palgrave. pp.564

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    L

    link

    A connection between two objects; an instance of an association.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.617

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    M

    method

    In the UML the specific implementation to algorithm of an operation for a class. Informally, the software procedure that can be executed in response to a message.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.617

    model

    A description of static and/or dynamic characteristics of a subject area, portrayed through a number of views (usually diagrammatic or textual)

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.617

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    O

    object class

    An object class defines that attributes and operations of objects. Objects are created at run-time by instantiating the class definition. The object class name can be used as a type name in some object-oriented language.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.766

    object model

    A model of a software system that is structured and organised as a set of object classes and the relationships between these classes. Various different perspectives on the model may exist such s a state perspective and a sequence perspective.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.766

    object-oriented (OO) development

    An approach to software development where the fundamental abstractions in the system are independent objects. The same type of abstraction is used during specification, design and development

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.766

    observation

    This research technique is important as a means of gaining detailed data on what people actually do. The observer may participate in the activities of the observed group or be independent of these activities. Observation may also be explicit or illicit.

    Data source: Beynon-Davies p, 2002 "Information systems: An introduction to informatics in organisations" , 1st Edition, Palgrave. pp.564

    OID

    Object Identifier

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.617

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    P

    pattern

    A pattern is a named description of a problem, solution, when to apply the solution, and how to apply the solution in new contexts.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.617

    postcondition

    A constraint that must hold true after the completion of an operaton.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.622

    precondition

    A constraint that must hold true before an operation is requested

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.618

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    R

    requirement management

    The process of managing changes to requirements to ensure that the changes made are properly analysed and tracked through the system.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.769

    requirement, functional

    a statement of some function or feature that should be implemented in a system.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.769

    requirement, non-functional

    A statement of a constraint or expected behaviour that applies to a system. This constraint may refer to the emergent properties of the software that is being developed or to the development process.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.769

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    S

    scenario

    A description of one typical way in which a system is used or a user carries out some activity.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.770

    scenario testing

    An approach to software testing where test cases are derived from a scenario of system use.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.770

    sequence diagram

    A diagram that shows the sequence of interactions required to complete some operation. In the UML, sequence diagrams ma be associated with use cases.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.771

    stakeholder

    The group of people to which an information system is relevant

    Data source: Beynon-Davies p, 2002 "Information systems: An introduction to informatics in organisations" , 1st Edition, Palgrave. pp.591

    stakeholder analysis

    Analysing the types of and impact of stakeholders on information systems

    Data source: Beynon-Davies p, 2002 "Information systems: An introduction to informatics in organisations" , 1st Edition, Palgrave. pp.591

    stakeholder involvement

    Involvement of stakeholder representatives in the development of an IT system.

    Data source: Beynon-Davies p, 2002 "Information systems: An introduction to informatics in organisations" , 1st Edition, Palgrave. pp.591

    stakeholder participation

    involvement of stakeholders both in the development of the IT system and the work surrounding its use.

    Data source: Beynon-Davies p, 2002 "Information systems: An introduction to informatics in organisations" , 1st Edition, Palgrave. pp.591

    stakeholder resistance

    The resistance of stakeholder groups to the introduction of some information system

    Data source: Beynon-Davies p, 2002 "Information systems: An introduction to informatics in organisations" , 1st Edition, Palgrave. pp.591

    stakeholder satisfaction

    The state of satisfaction expressed by some stakeholder group in an information system

    Data source: Beynon-Davies p, 2002 "Information systems: An introduction to informatics in organisations" , 1st Edition, Palgrave. pp.591

    state

    The condition of an object between events.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.618

    subclass

    A speciatlisation of another class (the supperclass). A subclass inherits the attributes and methods of the superclass.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.618

    superclass

    A class from which another class inherits attributes and methods.

    Data source: Larman c. 2002 "Applying UML and Patterns", 2nd, Pearson. Pp.619

    system

    A system is a purposeful collection of interrelated components, of different kinds, which work together to deliver a set of services to the system owner and users.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.772

    system engineering

    A process that is concerned with specifying a system, integrating its components and testing that the system meets its requirements. System engineering is concerned with the whole socio-technical system-software, hardware and operational process-not just the system software.

    Data source: Sommerville I. 2016 "Software Engineering" 10th Edition. Pearson Pp.772-773

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    U

    unified modelling language(UML)

    A graphical language used in object-oriented development that includes several types of system models that provide different views of a system. The UML has become a de facto standard for object-oriented modelling.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.773

    use case

    "Use case represents something of value that the system does for its actors. A use case defines a sequence of actions performed by a system that produces an observable result of value to an actor."

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.773

    use-case modelling

    A use-case model consists of both diagrams and text. The text gives descriptions of the actors and the use case.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.773

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    V

    validation

    The process of checking that a system meets the needs and expectations of the customer.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.774

    verification

    The process of checking that a system meets its specification.

    Data source: Sommerville I. 2016"Software Engineering" 10th Edition. Pearson Pp.774

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