Class definition in Java - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a class named "Car".

Java

public [1] Car {
    // class body
}

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Apackage

Bclass

Cmethod

Dinterface

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'interface' instead of 'class'.

Using 'method' which is not a keyword for class definition.

The keyword class is used to define a class in Java.

2fill in blank

medium

Complete the code to declare a private integer field named "speed" inside the class.

Java

public class Car {
    [1] int speed;
}

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Aprivate

Bpublic

Cprotected

Dstatic

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'public' which allows access from anywhere.

Using 'static' which is not an access modifier.

The keyword private restricts access to the field within the class only.

3fill in blank

hard

Fix the error in the constructor definition to properly initialize the "speed" field.

Java

public class Car {
    private int speed;

    public Car(int [1]) {
        speed = [1];
    }
}

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

AspeedValue

Bspeed

Cvalue

DspeedInput

Attempts:

3 left

💡 Hint

Common Mistakes

Using the same name for parameter and field without 'this' keyword.

Not assigning the parameter to the field.

The constructor parameter should have a different name than the field to avoid confusion. Here, value is used, and then assigned to the field speed.

4fill in blank

hard

Fill both blanks to create a method named "getSpeed" that returns the speed.

Java

public class Car {
    private int speed;

    public [1] [2]() {
        return speed;
    }
}

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Aint

Bvoid

CgetSpeed

DsetSpeed

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'void' as return type which means no value is returned.

Naming the method 'setSpeed' which is used to set a value.

The method getSpeed returns an integer value, so its return type is int.

5fill in blank

hard

Fill all three blanks to create a setter method named "setSpeed" that sets the speed field.

Java

public class Car {
    private int speed;

    public [1] [2]([3] newSpeed) {
        speed = newSpeed;
    }
}

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

Avoid

Bint

CsetSpeed

Dspeed

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'int' as return type for setter methods.

Using wrong method name like 'speed' instead of 'setSpeed'.

The setter method setSpeed does not return a value, so its return type is void. It takes an int parameter named newSpeed.