Composition over inheritance in LLD - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a class that uses composition to include a Logger component.

LLD

class Application:
    def __init__(self):
        self.logger = [1]()

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ALogger

BInheritance

CComponent

DInterface

Attempts:

3 left

💡 Hint

Common Mistakes

Using inheritance keyword instead of creating an instance.

The Application class uses composition by creating an instance of the Logger class inside it.

2fill in blank

medium

Complete the code to delegate the log message to the composed Logger object.

LLD

class Application:
    def __init__(self):
        self.logger = Logger()
    def log(self, message):
        self.logger.[1](message)

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Alog

Bwrite

Cprint

Dsend

Attempts:

3 left

💡 Hint

Common Mistakes

Using a method name that does not exist in Logger.

The Application class calls the log method of the Logger instance to delegate logging.

3fill in blank

hard

Fix the error in the code to properly use composition instead of inheritance.

LLD

class Logger:
    def log(self, message):
        print(message)

class Application([1]):
    def __init__(self):
        self.logger = Logger()

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AApplication

BLogger

Cobject

DComponent

Attempts:

3 left

💡 Hint

Common Mistakes

Inheriting from Logger instead of using it as a component.

The Application class should not inherit from Logger but from object to use composition properly.

4fill in blank

hard

Fill both blanks to complete the code that shows composition with two components.

LLD

class Application:
    def __init__(self):
        self.logger = [1]()
        self.database = [2]()

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ALogger

BDatabase

CComponent

DService

Attempts:

3 left

💡 Hint

Common Mistakes

Using generic names instead of actual component classes.

The Application class composes Logger and Database components by creating their instances.

5fill in blank

hard

Fill all three blanks to complete the code that delegates methods to composed components.

LLD

class Application:
    def __init__(self):
        self.logger = Logger()
        self.database = Database()
    def log(self, message):
        self.logger.[1](message)
    def save(self, data):
        self.database.[2](data)
    def load(self, id):
        return self.database.[3](id)

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

Alog

Bsave

Cload

Dprint

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect method names that do not exist in components.

The Application class delegates log, save, and load calls to the respective component methods.