Which of the following patterns can be used for designing your class to add erro

ID: 3828445 • Letter: W

Question

Which of the following patterns can be used for designing your class to add error checking such as not allowing a blank name for a bank account?

Question options:

Describing the Position of an Object

Modeling Objects with Distinct States

Managing Properties of an Object

Collecting Values

Question 4

0 / 1 point

Consider the following class which is used to represent a polygon consisting of an arbitrary number of (x, y) points:

class Polygon :

def __init__(self) :

self._x_points = []

self._y_points = []

Which of the following code segments is the correct implementation for the addPoint method that adds another point to the polygon?

Question options:

def addPoint(self, x, y) :

self._points.append(x, y)

def addPoint(self, x, y) :

self._x_points.append(x)

self._y_points.append(y)

def addPoint(self, x, y) :

self._x_points = x

self._y_points = y

def addPoint(self, x, y) :

self._x_points = [x]

self._y_points = [y]

Question 6

0 / 1 point

Which of the following method headers represent a constructor for an Employee class?

Question options:

def Employee(self) :

def __init()__ :

def __Employee__(self) :

def __init__(self) :

Question 7

0 / 1 point

What part of the virtual machine is responsible for removing objects that are no longer referenced?

Question options:

The allocator

The garbage collector

The recycler

The regenerator

Question 11

0 / 1 point

Which of the following is NOT a true statement regarding object-oriented programming?

Question options:

Object oriented programming views the program as a list of actions to perform.

Object oriented programs usually contain different types of objects, each corresponding to a particular kind of complex data, real-world object or concept.

Object oriented programming is a style where tasks are solved by collaborating objects.

Object oriented programs are organized around "objects" rather than "actions" and "data" rather than "logic".

Question 13

0 / 1 point

Given the following code snippet, what statement completes the code to add several items to one grocery list:

def addItems(self, price, quantity, itemName) :

for i in range(quantity) :

________________________

def addItem(self, price, itemName) :

self._itemCount = self._ItemCount + 1

self._totalPrice = self._totalPrice + price

. . .

Question options:

self.addItem(price, itemName)

addItem(price, itemName)

self._addItem(price, itemName)

_addItem(price, itemName)

Question 17

0 / 1 point

What is the name of the method in the following code segment?

class Fruit :

def getColor(self) :

return self._color

Question options:

_color

Fruit

getColor

self

Question 18

0 / 1 point

Consider the following class:

class Counter :

def getValue(self) :

return self._value

def click(self) :

self._value = self._value + 1

def unClick(self) :

self._value = self._value - 1

def reset(self) :

self._value = 0

Which method creates a new instance variable?

Question options:

click

getValue

reset

unClick

Question 19

0 / 1 point

What change needs to be made in the following code segment so that lName will have a default value of "unknown"?

class PhoneNumber :

def __init__(self, lName, phone = "215-555-1212") :

self._name = lName

self._phone = phone

Question options:

Replace self._name = lName with self._name = "unknown"

Replace the lName parameter with lName = "unknown"

Add name = "unknown" to the end of the constructor

Add self._lName = "unknown" to the end of the constructor

Question 20

0 / 1 point

Suppose you have a class ShoppingList, with instance variables _quantity, _cost, and _itemName. How should you access these variables when writing code that is not contained within the ShoppingList class?

Question options:

Directly access the instance variables by using the object and the instance variables' names.

Use methods provided by the ShoppingList class.

It is not possible to access the instance variables outside of the ShoppingList class.

Use the self parameter followed by the instance variables' names.

Given the variable assignment sentence = "", what is the value of len(sentence)?

Question options:

-1

an exception is raised

Question 13

0 / 1 point

Recall the Cash Register class developed in the textbook. What is output by the following code segment?

from cashregister2 import CashRegister

reg1 = CashRegister()

reg2 = reg1

reg1.addItem(3.00)

reg1.addItem(5.00)

reg2.clear()

print(reg1.getCount())

Question options:

The program terminates with a runtime error

Question 16

0 / 1 point

What happens when an object is no longer referenced?

Question options:

Nothing until the problem terminates

The garbage collector removes the object

The address is saved for future instances of the object

Creates a None reference

Question 18

0 / 1 point

Which statement is NOT a description of encapsulation?

Question options:

The act of hiding the implementation details

A collection of methods through which the objects of the class can be manipulated

Enables changes in the implementation without affecting users of a class

Mechanism for restricting access to some of the object's components

Which of the follow code segments could be used to help test the getColor method from the Fruit class?

Question options:

print(f.getColor())

print("Expected: Yellow")

print("Yellow")

print("Expected: Yellow")

print(f.getColor())

print("Expected:", f.getColor())

print("Yellow")

print("Expected:", f.getColor())

Question 2

0 / 1 point

Which of the following patterns can be used for designing your class to update the balance of a bank account?

Question options:

Keeping a total

Counting events

Collecting values

Managing properties of an object

Question 3

0 / 1 point

Consider a class that represents a hardware device. The device can be in one of two states: Plugged in, or unplugged. Which of the following class definitions is best for this situation?

Question options:

PLUGGED_IN = 0

UNPLUGGED = 1

class Device :

def __init__(self) :

. . .

class Device :

PLUGGED_IN = 0

UNPLUGGED = 1

def __init__(self) :

. . .

class Device :

def __init__(self) :

PLUGGED_IN = 0

UNPLUGGED = 1

. . .

class Device :

def __init__(self) :

self.PLUGGED_IN = 0

self.UNPLUGGED = 1

. . .

Question 6

0 / 1 point

Which of the following is NOT a pattern used to help design the data representation of a class?

Question options:

An instance variable for thte total is updated in methods that increase or decrease the total amount

An object reference specifies the location of an object

An object can collect other objects in a list

To model a moving object, you need to store and update its position

Question 9

0 / 1 point

Consider the following class:

class Contact :

def __init__(self, name, phone="")

self._name = name

self._phone = phone

def getName(self) :

return self._name

def setName(self, new_name) :

self._name = new_name

def getPhone(self) :

return self._phone

def setPhone(self, new_phone) :

self._phone = new_phone

What is output by the following code segment?

p1 = Contact("Bob", "555-123-4567")

p2 = Contact("Joe", "555-000-0000")

p1.setName(p2.getName())

print(p1.getPhone())

Question options:

Bob

Joe

555-000-0000

555-123-4567

Question 10

0 / 1 point

How many constructors can be defined for each class?

Question options:

At least one must be defined

Only one may be defined

At least one, but as many as needed

At least one, but no more than five

Question 11

0 / 1 point

Which of the following is NOT true about instance methods for a class?

Question options:

The object on which a method is applied is automatically passed to the self parameter variable of the method

In a method, you access instance variables through the self parameter variable

A class variable belongs to the class, not to any instance of the class

The accessor and mutator methods are automatically called when an object is created

Question 13

0 / 1 point

What is the value of the variable bankAcct after the following code snippet is executed?

bankAcct = BankAccount("Fisher", 1000.00)

Question options:

"Fisher", 1000.00

A memory location

"Fisher"

1000.00

Question 18

0 / 1 point

Consider the following class:

class Pet:

____________________

def __init__(self, name):

self._name = name

Pet._lastID = Pet._lastID + 1

self._registrationID = Pet._lastID

What line of code should be placed in the blank to create a class variable that keeps track of the most recently used registration identifier?

Question options:

_lastID = 0

Pet.append(_lastID)

Pet._lastID = 0

self._lastID = 0

Attempt Score:

6 / 10 - D

8 / 10 - B

Question 1

0 / 1 point

Before invoking a method on an object, what must be done first?

Question options:

Initialize all instance variables

Invoke the accessor and mutator methods

Create a public interface

Construct the object

Question 6

0 / 1 point

Which of the following questions should you ask yourself in order to determine if you have named your class properly?

Question options:

Does the class name contain 8 or fewer characters?

Is the class name a verb?

Can I visualize an object of the class?

Does the class name describe the tasks that this class will accomplish?

Question 8

0 / 1 point

Consider a class that represents a hardware device. The device can be in one of two states: Plugged in, or unplugged. Which of the following class definitions is best for this situation?

Question options:

PLUGGED_IN = 0

UNPLUGGED = 1

class Device :

def __init__(self) :

. . .

class Device :

PLUGGED_IN = 0

UNPLUGGED = 1

def __init__(self) :

. . .

class Device :

def __init__(self) :

PLUGGED_IN = 0

UNPLUGGED = 1

. . .

class Device :

def __init__(self) :

self.PLUGGED_IN = 0

self.UNPLUGGED = 1

. . .

Question 9

0 / 1 point

Which of the following is considered by the text to be the most important consideration when designing a class?

Question options:

Each class should represent an appropriate mathematical concept.

Each class should represent a single concept or object from the problem domain.

Each class should represent no more than three specific concepts.

Each class should represent multiple concepts only if they are closely related.

Question 16

0 / 1 point

Which name would be best for a private instance variable?

Question options:

_confidential

HIDDEN

private

Secret

Question 17

0 / 1 point

A method that queries an object for some information without changing it is known as a(n):

Question options:

Accessor

Function

Interface

Mutator

Question 19

0 / 1 point

Which of the following method headers represent a constructor for an Employee class?

Question options:

def Employee(self) :

def __init()__ :

def __Employee__(self) :

def __init__(self) :

Question 2

0 / 1 point

What items should be considered when creating the public interface?

Question options:

Method headers and method comments

Instance variables

Data and method bodies

Method implementations

Question 3

0 / 1 point

In the following example, which data is considered instance data?

You are assigned the task of writing a program that calculates payroll for a small company. To get started the program should do the following:

Add new employees including their first and last name and hourly wage

Ask for the number of hours worked

Calculate payroll (applying 1.5 for any hours greater than 40)

Print a report of all employees' salary for the week, total of all hours and total of all salaries

Question options:

firstName, lastName, hoursWorked, hourlyWage

firstName, lastName, hoursWorked, hourlyWage, payrollAmount

firstName, lastName, hoursWorked, hourlyWage, totalHours, totalSalary

firstName, lastName, hoursWorked, hourlyWage, payrollAmount, totalHours, totalSalary

Question 4

0 / 1 point

Which of the following is NOT a step carried out by a tester program?

Question options:

Construct one or more objects of the class

Invoke one or more methods

Print out one or more results

Identify syntax errors

Question 16

0 / 1 point

What change needs to be made in the following code segment so that lName will have a default value of "unknown"?

class PhoneNumber :

def __init__(self, lName, phone = "215-555-1212") :

self._name = lName

self._phone = phone

Question options:

Replace self._name = lName with self._name = "unknown"

Replace the lName parameter with lName = "unknown"

Add name = "unknown" to the end of the constructor

Add self._lName = "unknown" to the end of the constructor

Question 20

0 / 1 point

Which of the following is NOT a difference between methods and functions?

Question options:

A method is defined within a class. A function is defined outside of a class.

A function is defined within a class. A method is defined outside of a class.

The first parameter variable for a method is self. Functions do not have a self parameter variable.

A method can access the instance variables of an object. A function cannot.

Question 1

0 / 1 point

Assume a class exists named Fruit. Which of the follow statements constructs an object of the Fruit class?

Question options:

def Fruit() :

class Fruit() :

x = Fruit()

x = Fruit.create()

Question 5

0 / 1 point

Assume that x is a variable containing an object reference. Which special method is invoked when the following statement executes?

print(x)

Question options:

__init__

__print__

__repr__

__str__

Question 6

0 / 1 point

How do you access instance variables in a method?

Question options:

Using the constructor

Using the public interface

Using a default value

Using the self reference

Question 7

0 / 1 point

Consider the following code segment:

class PhoneNumber :

def __init__(self, lName, phone = "215-555-1212") :

self._name = lName

self._phone = phone

def getName(self):

return self._name

def getPhone(self):

return self._phone

Jones = PhoneNumber("Jones")

print(Jones.getName(), Jones.getPhone())

What will be printed when it executes?

Question options:

Jones 215-555-1212

AttributeError: 'PhoneNumber' object has no attribute

Jones

Jones 000-000-0000

Question 8

0 / 1 point

What is the purpose of an object's instance variables?

Question options:

Store the data required for executing its methods

Store the data for all objects created by the same class

To provide access to the data of an object

To create variables with public visibility

Question 11

0 / 1 point

Consider the following code segment:

def mutate(self, newType) :

self._type = newType

self._mutations = self._mutations + 1

What is the name of the local variable in it:

Question options:

mutate

_mutations

newType

_type

Question 13

0 / 1 point

When is a constructor invoked?

Question options:

When an object is created

When instance data is modified

When a method is invoked

When multiple arguments are required to create an object

Question 15

0 / 1 point

Which of the following statements determines if x currently refers to an object containing an integer?

Question options:

if int(x) :

if x == int :

if x is int :

if isinstance(x, int) :

Question 20

0 / 1 point

Assume a class exists named Person. Which of the follow statements constructs an object of the Person class?

Question options:

bob = __init__(Person)

bob = Person.__init__()

bob = Person

bob = Person()

Describing the Position of an Object

Modeling Objects with Distinct States

Managing Properties of an Object

Collecting Values

Question 4

0 / 1 point

Explanation / Answer

Question 4 => Managing Properties of an Object
object properties can be managed to perform error checking

Question 6
=> def addPoint(self, x, y) :
self._x_points.append(x)
self._y_points.append(y)
append new point to x and y list

Question 7 => def __init__(self) :

Question 11 => The garbage collector

Question 13 => Object oriented programming views the program as a list of actions to perform.

Question 17 => self.addItem(price, itemName)

Question 18 => getColor


Question 19 => click

Question 20
Replace the lName parameter with lName = "unknown"

=> Use methods provided by the ShoppingList class.

Question 13
=> 0

Question 16
=> 2

Question 18
=> The garbage collector removes the object

=> A collection of methods through which the objects of the class can be manipulated

Question 2
=>
print("Yellow")
print("Expected:", f.getColor())

Question 3
=> Managing properties of an object

Question 6
=> def __init__(self) :
self.PLUGGED_IN = 0
self.UNPLUGGED = 1

Question 9
=> An object reference specifies the location of an object

Question 10
=> 555-123-4567

Question 11
=> At least one, but as many as needed

Question 13
=> A class variable belongs to the class, not to any instance of the class

Question 18
=> A memory location

Question 1
=> _lastID = 0

Question 6
=> Construct the object

Question 8
=> Does the class name describe the tasks that this class will accomplish?

Question 9
class Device :
def __init__(self) :
self.PLUGGED_IN = 0
self.UNPLUGGED = 1

Question 16
=> Each class should represent a single concept or object from the problem domain.

Question 17
=> private

Question 19
=> Acessor

Question 2
=> def __init__(self) :

Question 3
=> Method headers and method comments

Question 4
=> firstName, lastName, hoursWorked, hourlyWage

Question 16
=> Identify syntax errors

Question 20
=> Replace the lName parameter with lName = "unknown"

Question 1
=> A function is defined within a class. A method is defined outside of a class.

Question 5
=> x = Fruit()

Question 6
=> __str__

Question 7
=> Using the self reference

Question 8
=> Jones 215-555-1212

Question 11
=> Store the data required for executing its methods

Question 13
=> newType

Question 15
=> When an object is created

Question 20
=> if isinstance(x, int) :

=> bob = Person()

Navigate

Which of the following pattern is considered to be between sister chromatids 2 &

Which of the following peaks are NOT expected to be present in the IR spectrum o

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.

Which of the following patterns can be used for designing your class to add erro

Question

Explanation / Answer

Related Questions

Navigate