Why behavioral patterns define object interaction in LLD - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to show how behavioral patterns focus on {{BLANK_1}}.

LLD

class Observer:
    def update(self, [1]):
        pass

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

Astate

Bclass

Cmethod

Dvariable

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing state with class or method names.

Behavioral patterns define how objects communicate by changing their state and notifying others.

2fill in blank

medium

Complete the code to illustrate object interaction in behavioral patterns.

LLD

class Subject:
    def __init__(self):
        self.observers = []

    def attach(self, observer):
        self.observers.[1](observer)

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

Aremove

Bappend

Cclear

Dpop

Attempts:

3 left

💡 Hint

Common Mistakes

Using remove or pop which delete items instead of adding.

Objects interact by adding observers to a list using append to notify them later.

3fill in blank

hard

Fix the error in the code that manages object interaction.

LLD

class Command:
    def execute(self):
        [1]

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

Aexecute()

Breturn

Cpass

Dself.execute()

Attempts:

3 left

💡 Hint

Common Mistakes

Calling execute() inside itself causing infinite recursion.

The base Command class defines an empty execute method using pass to be overridden by subclasses.

4fill in blank

hard

Fill both blanks to complete the interaction between objects in the Chain of Responsibility pattern.

LLD

class Handler:
    def __init__(self, successor=None):
        self.successor = [1]

    def handle(self, request):
        if self.can_handle(request):
            self.process(request)
        else:
            if self.successor is not [2]:
                self.successor.handle(request)

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

Asuccessor

BNone

Cself

Drequest

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong variable names or forgetting to check for None.

The handler stores the next handler as successor and checks if it is not None before passing the request.

5fill in blank

hard

Fill all three blanks to complete the Mediator pattern example showing object interaction.

LLD

class Mediator:
    def notify(self, sender, event):
        if event == [1]:
            self.colleague1.[2]()
        elif event == [3]:
            self.colleague2.action()

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

A"event1"

Brespond

C"event2"

Dstart

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing event names or method names incorrectly.

The mediator reacts to "event1" by calling respond on colleague1 and to "event2" by calling action() on colleague2.