Why structural patterns organize class relationships in LLD - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a structural pattern that connects classes.

LLD

class Adapter:
    def __init__(self, adaptee):
        self.adaptee = adaptee

    def request(self):
        return self.adaptee.[1]()

Drag options to blanks, or click blank then click option'

Aunrelated_method

Bgeneral_request

Cspecific_request

Dundefined_method

Attempts:

3 left

💡 Hint

Common Mistakes

Using a method name that does not exist in the adaptee.

The Adapter pattern wraps an adaptee's specific method to match the expected interface.

2fill in blank

medium

Complete the code to show how a decorator adds behavior to a class.

LLD

class Component:
    def operation(self):
        return "Component operation"

class Decorator(Component):
    def __init__(self, component):
        self.component = component

    def operation(self):
        return self.component.operation() + [1]

Drag options to blanks, or click blank then click option'

A" with added behavior"

Bself.component.operation()

C" base behavior"

Dself.operation()

Attempts:

3 left

💡 Hint

Common Mistakes

Calling self.operation() recursively causing infinite loop.

The decorator extends the original operation by adding extra behavior as a string.

3fill in blank

hard

Fix the error in the composite pattern code to correctly add child components.

LLD

class Composite:
    def __init__(self):
        self.children = []

    def add(self, component):
        self.children.[1](component)

Drag options to blanks, or click blank then click option'

Aadd

Bappend

Cinsert

Dextend

Attempts:

3 left

💡 Hint

Common Mistakes

Using add which is not a list method in Python.

To add a single component to the children list, use the append method.

4fill in blank

hard

Fill both blanks to complete the proxy pattern that controls access to a resource.

LLD

class Proxy:
    def __init__(self, real_subject):
        self.real_subject = real_subject

    def request(self):
        if self.check_access():
            return self.real_subject.[1]()
        else:
            return [2]

Drag options to blanks, or click blank then click option'

Arequest

B"Access denied"

CNone

Dcheck_access

Attempts:

3 left

💡 Hint

Common Mistakes

Returning None instead of an access denied message.

The proxy calls the real subject's request method if access is allowed; otherwise, it returns an access denied message.

5fill in blank

hard

Fill all three blanks to complete the flyweight pattern that shares objects efficiently.

LLD

class FlyweightFactory:
    def __init__(self):
        self._flyweights = {}

    def get_flyweight(self, key):
        if key not in self._flyweights:
            self._flyweights[[1]] = Flyweight([2])
        return self._flyweights[[3]]

Drag options to blanks, or click blank then click option'

Akey

C"new_key"

DFlyweight

Attempts:

3 left

💡 Hint

Common Mistakes

Using different keys for storing and retrieving flyweights.

The factory uses the key to check and store flyweight objects, ensuring reuse.