Why constructors are needed in Java - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a constructor for the class.

Java

public class Car {
    String model;
    public [1](String model) {
        this.model = model;
    }
}

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Apublic Car()

Bcar

Cvoid Car

DCar

Attempts:

3 left

💡 Hint

Common Mistakes

Using a lowercase name for the constructor.

Adding a return type like void.

The constructor name must exactly match the class name and have no return type.

2fill in blank

medium

Complete the code to create an object using the constructor.

Java

Car myCar = new [1]("Toyota");

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AVehicle

Bcar

CCar

DMyCar

Attempts:

3 left

💡 Hint

Common Mistakes

Using a lowercase class name.

Using a different class name.

To create an object, use the class name with the new keyword and call the constructor.

3fill in blank

hard

Fix the error in the constructor declaration.

Java

public class Book {
    String title;
    public void [1](String title) {
        this.title = title;
    }
}

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ABook()

BBook

Cvoid Book

Dbook

Attempts:

3 left

💡 Hint

Common Mistakes

Adding a return type to the constructor.

Using lowercase for the constructor name.

Constructors must not have a return type, so remove 'void' and use the class name exactly.

4fill in blank

hard

Fill both blanks to complete the constructor and initialize the field.

Java

public class Student {
    int age;
    public [1](int [2]) {
        this.age = age;
    }
}

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AStudent

Bstudent

Cage

Dyears

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase constructor name.

Using a different parameter name than the field.

The constructor name must match the class name 'Student'. The parameter name should be 'age' to assign correctly.

5fill in blank

hard

Fill all three blanks to create a constructor that initializes two fields.

Java

public class Laptop {
    String brand;
    int price;
    public [1](String [2], int [3]) {
        this.brand = brand;
        this.price = price;
    }
}

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ALaptop

Bbrand

Cprice

Dlaptop

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase constructor name.

Using wrong parameter names.

The constructor name must be 'Laptop'. The parameters should be 'brand' and 'price' to assign values correctly.