Module 3 Chapter 6 Review
Although the term ___________ usually refers to a particular instance, systems analysts sometimes use the term to refer to a ____________. Usually the meaning is understood from the context and the way the term is used.
--"object" --class of objects
Sequence diagrams include symbols that represent
1. Classes 2. Lifelines 3. Messages 4. Focuses
The most popular systems development options are: ·
1. structured analysis 2. object-oriented (O-O) analysis 3. agile methods, also called adaptive methods
_______________ is identified by a rectangle with the name inside. Classes that send or receive messages are shown at the top of the sequence diagram.
A class
_____________is a group of similar objects. For example, Ford Fiestas belong to a class called CAR.
A class
_________________ shows the object classes and relationships involved in a use case.
A class diagram
______________ indicates when an object sends or receives a message. ______________ is identified by a narrow vertical shape that covers the lifeline.
A focus
________________ is identified by a dashed line.
A lifeline
________________ is identified by a line showing direction that runs between two objects. The label shows the name of the message and can include additional information about the contents.
A message
is a command that tells an object to perform a certain method.
A message
__________ defines specific tasks that an object can perform.
A method
________________ is a dynamic model of a use case, showing the interaction among classes during a specified time period.
A sequence diagram
Inheritance ___________
A type of object relationship.
________________ represents the steps in a specific business function or process.
A use case
__________________ the name of the use case, the actor, a description of the use case, a step-by-step list of the tasks and actions required for successful completion, a description of alternative courses of action, preconditions, postconditions, and assumptions.
A use case description documents
_________________ is a visual summary of several related use cases within a system or subsystem.
A use case diagram
________________ when a bank account could be opened as a NEW account, change to an ACTIVE or EXISTING account, and eventually become a CLOSED or FORMER account. Another possible state for a bank account could be FROZEN, if the account's assets are legally attached.
An example of State transition is
_________________ when a hotel customer reserves a room, the reservation system blocks a room, updates the occupancy forecast, and sends the customer a confirmation. Those events are all part of a single use case called Reserve Room, and the specific actions are step-by-step tasks within the use case.
An example of a single use case,
__________ a student can be a future student, a current student, or a past student. or a bank account can be active, inactive, closed, or frozen.
An example of a state
________________in a medical office system, a PATIENT (actor) can MAKE APPOINTMENT (use case).
An example of an actor
when a patient makes an appointment to see a doctor, the patient is an __________, the doctor is an________, and the appointment itself is an _________.
An example of an object
______________the INSTRUCTOR object (child) inherits many traits from the EMPLOYEE object (parent), including Social Security number, Telephone number, and Hire date. The INSTRUCTOR object also can possess additional attributes, such as Type of Instructor. Because all employees share certain attributes, those attributes are assumed through inheritance and do not need to be repeated in the INSTRUCTOR object.
An example of an object in inheritance
_______________ an employee might have earned no vacation days or one vacation day or many vacation days. Or an employee might have no spouse or one spouse.
An example of cardinality,
_______________-TRUCK objects represent a subclass within the VEHICLE class, along with other subclasses called CAR, MINIVAN, and SCHOOL BUS. Notice that all four subclasses share common traits of the VEHICLE class, such as make, model, year, weight, and color. Each subclass also can possess traits that are uncommon, such as a load limit for the TRUCK or an emergency exit location for the SCHOOL BUS.
An example of subclasses are
_____________ a NOVEL class belongs to a superclass called BOOK, because all novels are books in this example. The NOVEL class can have subclasses called HARDCOVER, PAPERBACK, and DIGITAL.
An example of superclass
PICK UP TOYS directs the CHILD class to perform all the necessary steps to pick up the toys. The CHILD class understands the message and executes the method.
An example of the message
___________ is a specific member of a class. A Toyota Camry, for example, is an instance of the CAR class.
An instance
_______________ represents a real person, a place, an event, or a transaction.
An object
Creating the diagrams by hand is time consuming and tedious, so systems analysts rely on ___________________________
CASE tools to speed up the process and provide an overall framework for documenting the system components.
_________________ is the object that derives one or more attributes from another object, called the parent.
Child In inheritance,
______________ is a detailed view of a single use case, showing the classes that participate in the use case, and documenting the relationship among the classes.
Class diagram
a car performs a ____________ called OPERATE WIPERS when it is sent a message with the wiper control, and it can APPLY BRAKES when it is sent a message by pressing the brake pedal.
Examples of methods are
________________ , each class appears as a rectangle, with the class name at the top, followed by the class's attributes and methods. Lines show relationships between classes and have labels identifying the action that relates the two classes.
In a class diagram
________________ , ___________ appear as rounded rectangles with the state names inside.
In a state transition diagram
_________objects can inherit, or acquire, certain attributes from other objects.
In an O-O system
________________ is popular because it integrates easily with O-O programming languages such as Java, Smalltalk, VB.Net, Python, and Perl. Programmers also like O-O code because it is modular, reusable, and easy to maintain.As the table indicates,
O-O methodology
____________ Describes objects, which combine data and processes. Object models are the end product of object-oriented analysis.
Object model
_____________ is the object from which the other object, the child, derives one or more attributes.
Parent In inheritance
· enable objects to communicate and interact as they perform business functions and transactions required by the system.
Relationships
_______________ what objects need to know about each other, how objects respond to changes in other objects, and the effects of membership in classes, superclasses, and subclasses.
Relationships describe
______________________ are dynamic modeling tools that can help a systems analyst understand how objects behave and interact with the system.
Sequence diagrams, state transition diagrams, and activity diagrams
_______________ includes the steps required to heat the oil, fill the fry basket with frozen potato strips, lower it into the hot oil, check for readiness, remove the basket when ready and drain the oil, pour the fries into a warming tray, and add salt.
The MORE FRIES method
______________ can perform methods, such as reading a bedtime story, driving the carpool van, or preparing a school lunch.
The PARENT object
_________________is shown as a stick figure, with a label that identifies the actor's role.
The actor
to understand basic O-O terms, including objects, attributes, methods, messages, classes, and instances.
The first step in developing an object model is
______________are that systems analysts can save time and avoid errors by using modular objects, and programmers can translate the designs into code, working with reusable program modules that have been tested and verified.
The major advantages of O-O designs
__________________ what is included in the system (inside the rectangle) and what is not included in the system (outside the rectangle).
The system boundary shows
_________________ The objective is to identify the actors and the functions or transactions they initiate.
To create a use case,
_________________ start by reviewing the information that gathered during the requirements modeling phase.
To create use cases,
___________is used to develop object models.
UML
___________ is a widely used method of visualizing and documenting an information system.
Unified Modeling Language (UML)
_____________ receives a message, it performs an action, or method.·
When a PARENT object
because a message to the object triggers changes within the object without specifying how the changes must be carried out.
Why an object can be viewed as a black box
__________ might have certain attributes such as name, age, sex, and hair color.
a PARENT object
Examples of attributes are ______________
a car has attributes such as make, model, and color.
Like a DFD, ___________________ , which evolves into a physical model and finally becomes a functioning information system.
a class diagram is a logical model
All objects within a class share common attributes and methods, so ___________
a class is like a blueprint, or template for all the objects within the class.
To signal the CHILD object to perform tasks, _____________
a parent can send certain messages that the CHILD object will understand.
· UML represents an object as ________________.
a rectangle with the object name at the top, followed by the object's attributes and methods
When use cases are identified, all the related transactions should be grouped into ______________________ .
a single use case
Objects can have a specific attribute called
a state
The state of an object is an ________________
adjective that describes the object's current status.
encapsulation means that _____________
all data and methods are self-contained.
The end product of O-O analysis is ____________, which represents the information system in terms of objects and O-O concepts.
an object model
By limiting access to internal processes, ________________
an object prevents its internal code from being altered by another object or process.·
_______________ can be prepared to provide an overview of the system.
an object relationship diagram
Inheritance enables __________________
an object to derive one or more of its attributes from another object.
BPM is a requirement modeling tool, but it can be used ________________________
anytime during the systems development process.
The diagrams and documentation __________________, so accuracy is important.
are the foundation for the system's design
_________ are similar to adjectives that describe the characteristics of an object
attributes
· Objects have ___________, can send and receive messages, and perform actions called methods.·
attributes
The line from the actor to the use case is called an association, ________________
because it links a particular actor to a use case.
Encapsulation allows objects to be used as modular components anywhere in the system, _______________________
because objects send and receive messages but do not alter the internal methods of other objects.
__________________ can be used to represent the people, events, and interaction in a system.
business process models (BPM)
The same message to two different objects ___________ .
can produce different results
The class diagram also includes a concept called , _____________ which describes how instances of one class relate to instances of another class.
cardinality
· An object belongs to a group or category called a __________.
class
evolve into code modules, data objects, and other system components.
class diagrams
If a CASE-generated model is not used, each diagram or object definition should be supported by ______________________
clear, relevant documentation that can be accessed easily by anyone who reviews the object model.
An object, however, includes _________________
data and the processes that affect that data.
UML is a popular technique for _________________
documenting and modeling a system.
Systems analysts define an object's attributes ________________
during the systems design process.
The black box concept is an example of ________________
encapsulation
There are many ways to proceed with the task of organizing the object model, and _____________________
experience is the best teacher.
Some objects might have a _____________
few attributes; others might have dozens.
For example, a customer object ________________·
has a name, an address, an account number, and a current balance. ___________ also can perform specific tasks, such as placing an order, paying a bill, and changing their address.
A state transition diagram shows __________________
how an object changes from one state to another, depending on events that affect the object.
When a use case diagram is created, the first step is to ____________________________
identify the system boundary, which is represented by a rectangle.
Object-oriented (O-O) analysis describes an information system by ___________ .
identifying things called objects
The strongest relationship is called ______________.
inheritance
An external entity, called an actor, ____________________
initiates a use case by requesting the system to perform a function or process.
Use cases also can ___________________
interact with other use cases.
the UML symbol for a use case ________________
is an oval with a label that describes the action or event.
Although the UML can be used for business process modeling and requirements modeling, _________________
it is mainly used to support O-O system analysis and to develop object models.
Remember that ____________________ than to change the software later.
it is much easier to repair a diagram now
· Object modeling requires ____________________
many types of diagrams to represent the proposed system.
· If objects are similar to
nouns
BPM works well with , ___________________ because both methods focus on the actors and the way they behave.
object modeling
A black box does not want or need _______________
outside interference
The concept that a message gives different meanings to different objects is called ____________.
polymorphism
To create a class diagram, ___________________
review the use case and identify the classes that participate in the underlying business process.
Object-oriented analysis is a popular approach that _____________________
sees a system from the viewpoint of the objects themselves as they function and interact.
After identifying the system's objects, classes, and relationships, an object relationship diagram _____________________
should be developed that provides an overview of the system.
· An activity diagram resembles a horizontal flowchart that _______________________
shows the actions and events as they occur.
All possible states must be documented in the ___________________
state transition diagram
A CHILD object performs certain methods, _____________
such as picking up toys, eating dinner, playing, cooperating, and getting ready for bed.
A class can belong to a more general category called a .
superclass
Just as structured analysis uses DFDs to model data and processes, __________________
systems analysts use UML to describe O-O systems.
For each use case, develop a use case description in the form of a _________.
table
methods resemble verbs _______________
that describe what and how an object does something.
If a CASE tool is used to develop the design, ______________________
the CASE software will perform much of the work automatically.
____________ possesses the same attributes as the PARENT object and an additional attribute that shows the number of siblings.
the CHILD object
The small circle to the left is ________________ or the point where the object first interacts with the system.
the initial state,
Reading from left to right, __________________ The circle at the right with a hollow border is the final state.
the lines show direction and describe the action or event that causes a transition from one state to another.
For example, _______________ PARENT object to read a bedtime story, but the same message to the CHILD object signals it to get ready for bed. the DOG object, the same message would tell the dog to sleep.
the message GOOD NIGHT signals the
The lifeline represents the time during which ___________________. An X marks the end of the lifeline.
the object is able to interact with the other objects in the use case.
By organizing the diagrams and documentation ________________________
the object model can be easily read and understood.
Activity diagrams show _______________________
the order in which the actions take place and identify the outcomes.
A sequence diagram graphically documents ________________________
the use case by showing the classes, the messages, and the timing of the messages
UML uses a set of symbols to represent graphically
the various components and relationships within a system.
If there are two parents, _____________
then there are two instances of the PARENT object.
In addition, CASE tools ensure consistency and provide common links so that once objects are described and used in one part of the design, ______________________________
they can be reused multiple times without further effort.
After the system boundary is identified, _____________________
use cases are placed on the diagram, the actors are added, and the relationships.
When the outcome of one use case is incorporated by another use case, _____________________
we say that the second case uses the first case.
An object has certain attributes,
which are characteristics that describe the object.
Objects within a class can be grouped into subclasses,
which are more specific categories within a class.
An object also has methods, _______________
which are tasks or functions that the object performs when it receives a message, or command, to do so.