Why organization scales test suites in JUnit - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a simple JUnit test method that checks if 5 is greater than 3.

JUnit

@Test
public void testNumberComparison() {
    assertTrue(5 [1] 3);
}

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

A<

B>

C==

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' instead of '>' causes the test to fail.

The test checks if 5 is greater than 3 using the > operator inside assertTrue.

2fill in blank

medium

Complete the code to assert that the string "hello" starts with "he".

JUnit

@Test
public void testStringStart() {
    assertTrue("hello".[1]("he"));
}

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

Acontains

BendsWith

CstartsWith

Dequals

Attempts:

3 left

💡 Hint

Common Mistakes

Using endsWith will check the end of the string, causing the test to fail.

The method startsWith checks if the string begins with the given substring.

3fill in blank

hard

Fix the error in the assertion that checks if two integers are equal.

JUnit

@Test
public void testEquality() {
    [1](10, 5 + 5);
}

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

AassertTrue

BassertNotNull

CassertFalse

DassertEquals

Attempts:

3 left

💡 Hint

Common Mistakes

Using assertTrue with equality check is less clear and may cause confusion.

assertEquals is used to check if two values are equal. The first argument is the expected value.

4fill in blank

hard

Fill both blanks to create a test that fails if the list is empty.

JUnit

@Test
public void testListNotEmpty() {
    List<String> items = List.of("apple", "banana");
    assertFalse(items.[1]() [2] 0);
}

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

Asize

BisEmpty

C==

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using isEmpty() with assertFalse and '>' causes logical errors.

The test checks that the list size is not equal to zero, meaning it is not empty.

5fill in blank

hard

Fill all three blanks to create a test that checks if a map contains a key and its value is not null.

JUnit

@Test
public void testMapKeyAndValue() {
    Map<String, String> map = Map.of("key1", "value1");
    assertTrue(map.[1]("key1") && map.get("key1") [2] null && !map.get("key1").[3]());
}

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

AcontainsKey

B!=

CisEmpty

Dequals

Attempts:

3 left

💡 Hint

Common Mistakes

Using equals() to compare with null causes NullPointerException.

The test confirms the map has the key, the value is not null, and the value is not empty.