Arrange-Act-Assert pattern in JUnit - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare the test method with the correct annotation.

JUnit

@[1]
public void testAddition() {
    // test code here
}

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AIgnore

BBefore

CAfter

DTest

Attempts:

3 left

💡 Hint

Common Mistakes

Using @Before or @After instead of @Test

Forgetting the '@' symbol

The @Test annotation marks a method as a test method in JUnit.

2fill in blank

medium

Complete the code to create an instance of Calculator in the Arrange step.

JUnit

public void testAddition() {
    Calculator calculator = new [1]();
    int result = calculator.add(2, 3);
    // assertions
}

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ACalculator

BAdd

CTest

DSum

Attempts:

3 left

💡 Hint

Common Mistakes

Using method names instead of class names

Using lowercase instead of class name capitalization

In the Arrange step, we create an object of the class we want to test, here Calculator.

3fill in blank

hard

Fix the error in the assertion statement to check the expected result.

JUnit

assertEquals([1], result);

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A"5"

Bresult

C5

Dtrue

Attempts:

3 left

💡 Hint

Common Mistakes

Using the actual result as expected value

Using a string instead of an integer

The expected value should be the number 5, not the variable or string.

4fill in blank

hard

Fill both blanks to complete the Arrange and Act steps correctly.

JUnit

Calculator calculator = new [1]();
int result = calculator.[2](4, 6);

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ACalculator

Badd

Csubtract

DCalculatorTest

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong class name for object creation

Calling a method that does not exist or is incorrect

We create a Calculator object and call its add method.

5fill in blank

hard

Fill all three blanks to complete the Arrange, Act, and Assert steps in the test method.

JUnit

@Test
public void testMultiply() {
    Calculator calculator = new [1]();
    int result = calculator.[2](3, 7);
    assertEquals([3], result);
}

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ACalculator

Bmultiply

C21

DCalculatorTest

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong class name

Calling wrong method

Asserting wrong expected value

The test creates a Calculator, calls multiply with 3 and 7, and asserts the result is 21.