Builder pattern in LLD - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare the Builder interface method for setting the product's name.

LLD

interface Builder {
    Builder setName([1] name);
}

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AString

Bint

Cvoid

Dboolean

Attempts:

3 left

💡 Hint

Common Mistakes

Using int or boolean instead of String for the name parameter.

Using void as a parameter type.

The setName method should accept a String parameter representing the product's name.

2fill in blank

medium

Complete the code to return the built product from the Builder.

LLD

class ProductBuilder implements Builder {
    private Product product = new Product();

    public Product [1]() {
        return product;
    }
}

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Acreate

Bbuild

CgetProduct

Dmake

Attempts:

3 left

💡 Hint

Common Mistakes

Using method names like create or make which are less standard.

Using getProduct which is verbose and less idiomatic.

The standard method name to return the final product in the Builder pattern is build().

3fill in blank

hard

Fix the error in the Director class method to correctly use the Builder to construct a product.

LLD

class Director {
    public Product construct(Builder builder) {
        builder.setName("Toy");
        builder.setPrice(10);
        return builder.[1]();
    }
}

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Amake

Bcreate

Cget

Dbuild

Attempts:

3 left

💡 Hint

Common Mistakes

Using create() or make() instead of build().

Forgetting to call the method to return the product.

The Director calls the build() method on the Builder to get the final product.

4fill in blank

hard

Fill both blanks to complete the fluent interface methods in the Builder implementation.

LLD

class ProductBuilder implements Builder {
    private Product product = new Product();

    public Builder setName([1] name) {
        product.name = name;
        return [2];
    }
}

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

AString

Bthis

Cproduct

Dvoid

Attempts:

3 left

💡 Hint

Common Mistakes

Returning void instead of this breaks chaining.

Using wrong parameter types like product or void.

The method parameter type is String for the name, and the method returns this to allow method chaining.

5fill in blank

hard

Fill all three blanks to complete the dictionary comprehension that maps product names to prices for products costing more than 100.

LLD

expensive_products = {product.[1]: product.[2] for product in products if product.[3] > 100}

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

Aname

Bprice

Dquantity

Attempts:

3 left

💡 Hint

Common Mistakes

Using quantity instead of price in the condition.

Mixing up keys and values in the dictionary comprehension.

The dictionary maps product name to price for products where price is greater than 100.