Payment strategy pattern in LLD - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare the PaymentStrategy interface.

LLD

interface [1] {
    void pay(int amount);
}

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

APayment

BPaymentStrategy

CPayStrategy

DPaymentMethod

Attempts:

3 left

💡 Hint

Common Mistakes

Using a class name instead of an interface name.

Choosing a name that does not reflect the strategy pattern.

The interface name should be PaymentStrategy to follow the pattern naming.

2fill in blank

medium

Complete the code to implement the pay method in CreditCardPayment class.

LLD

class CreditCardPayment implements PaymentStrategy {
    public void [1](int amount) {
        System.out.println("Paid " + amount + " using Credit Card.");
    }
}

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Apay

Bprocess

CmakePayment

Dexecute

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different method name than the interface.

Forgetting to implement the interface method.

The method must be named pay to implement the interface method.

3fill in blank

hard

Fix the error in the PaymentContext constructor to accept a PaymentStrategy.

LLD

class PaymentContext {
    private PaymentStrategy strategy;

    public PaymentContext([1] strategy) {
        this.strategy = strategy;
    }
}

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

AStrategy

BPaymentMethod

CPaymentStrategy

DPayment

Attempts:

3 left

💡 Hint

Common Mistakes

Using a concrete class type instead of the interface.

Mismatching parameter type and field type.

The constructor parameter type must be PaymentStrategy to accept any payment strategy.

4fill in blank

hard

Fill both blanks to complete the pay method call in PaymentContext.

LLD

class PaymentContext {
    private PaymentStrategy strategy;

    public void pay(int amount) {
        strategy.[1]([2]);
    }
}

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Apay

Bamount

Cprocess

Dvalue

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong method name like 'process'.

Passing wrong argument like 'value'.

The method pay is called with the amount parameter.

5fill in blank

hard

Fill all three blanks to create a PaymentContext with PayPalPayment and pay 100.

LLD

PaymentStrategy strategy = new [1]();
PaymentContext context = new PaymentContext([2]);
context.[3](100);

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APayPalPayment

Bstrategy

Cpay

DCreditCardPayment

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong payment class like CreditCardPayment.

Passing wrong variable to context.

Calling wrong method name.

Create a PayPalPayment instance, pass it as strategy to context, then call pay with amount 100.