TestInstance lifecycle per class in JUnit - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set the test instance lifecycle to per class.

JUnit

@TestInstance([1])
public class CalculatorTest {
    // test methods
}

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ATestInstance.Lifecycle.PER_CLASS

BTestInstance.Lifecycle.PER_METHOD

CTestInstance.Lifecycle.SINGLETON

DTestInstance.Lifecycle.PER_TEST

Attempts:

3 left

💡 Hint

Common Mistakes

Using PER_METHOD creates a new instance for each test method.

Using SINGLETON or PER_TEST are not valid lifecycle options.

The @TestInstance annotation with PER_CLASS sets the lifecycle so that one test instance is used for all tests in the class.

2fill in blank

medium

Complete the code to import the correct TestInstance annotation.

JUnit

import org.junit.jupiter.api.[1];

@TestInstance(TestInstance.Lifecycle.PER_CLASS)
public class CalculatorTest {
    // test methods
}

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ABeforeEach

BTest

CTestInstance

DAfterAll

Attempts:

3 left

💡 Hint

Common Mistakes

Importing Test instead of TestInstance.

Confusing lifecycle annotations with test method annotations.

The TestInstance annotation is imported from org.junit.jupiter.api to control test instance lifecycle.

3fill in blank

hard

Fix the error in the lifecycle annotation usage.

JUnit

@TestInstance(TestInstance.Lifecycle.[1])
public class CalculatorTest {
    // test methods
}

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APER_METHOD

BPER_CLASS

CPER_INSTANCE

DPER_TEST

Attempts:

3 left

💡 Hint

Common Mistakes

Using invalid enum values like PER_INSTANCE or PER_TEST.

Confusing PER_METHOD with PER_CLASS.

The correct lifecycle value to use for one instance per class is PER_CLASS. Other options like PER_INSTANCE or PER_TEST are invalid.

4fill in blank

hard

Fill both blanks to complete the test class with lifecycle per class and a test method.

JUnit

@TestInstance([1])
public class CalculatorTest {

    @Test
    public void testAdd() {
        int result = 2 + 3;
        assertEquals([2], result);
    }
}

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ATestInstance.Lifecycle.PER_CLASS

B5

C4

DTestInstance.Lifecycle.PER_METHOD

Attempts:

3 left

💡 Hint

Common Mistakes

Using PER_METHOD instead of PER_CLASS for lifecycle.

Asserting the wrong expected value in assertEquals.

The test instance lifecycle is set to PER_CLASS and the assertion checks that 2 + 3 equals 5.

5fill in blank

hard

Fill all three blanks to complete the test class with lifecycle per class, a test method, and an import.

JUnit

import org.junit.jupiter.api.[1];
import static org.junit.jupiter.api.Assertions.[2];

@TestInstance(TestInstance.Lifecycle.PER_CLASS)
public class CalculatorTest {

    @Test
    public void testMultiply() {
        int result = 3 * 4;
        [3](12, result);
    }
}

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ATestInstance

BassertEquals

CassertTrue

DassertFalse

Attempts:

3 left

💡 Hint

Common Mistakes

Importing wrong assertion methods like assertTrue or assertFalse.

Forgetting to import TestInstance.

The import for TestInstance is needed, the assertion method assertEquals is imported and used to check that 3 * 4 equals 12.