Junit 4 vs Junit 5

Architecture

Junit 4

• Monolithic : Everything is bundled into a single jar junit4.jar

Junit 5:

• Platform

   - Internal common library/utilities of JUnit
   - Public API for test engines
   - Public API for configuring and launching test plans.
   - Runner and annotations for configuring and executing tests.
  

• Jupiter

   - New junit annotations and TestEngine implementation to run tests written with these annotations.
   - Migration support from JUnit 4 to JUnit Jupiter
  

• Vintage

   - support running JUnit 3 and JUnit 4 written tests on the JUnit 5 platform.
  

Annotations

Features	JUnit 5	JUnit 4
Declares a test method	@Test	@Test
Denotes that the annotated method will be executed before all test methods in the current class	@BeforeAll	@ BeforeClass
Denotes that the annotated method will be executed after all test methods in the current class	@AfterAll	@AfterClass
Denotes that the annotated method will be executed before each test method	@BeforeEach	@Before
Denotes that the annotated method will be executed after each test method	@AfterEach	@After
Disable a test method or a test class	@Disable	@Ignore
Denotes a method is a test factory for dynamic tests in JUnit 5	@TestFactory	N/A
Denotes that the annotated class is a nested, non-static test class	@Nested	N/A
Declare tags for filtering tests	@Tag	@Category
Register custom extensions in JUnit 5	@ExtendWith	N/A

Assertions

JUnit 5	JUnit 4
fail	fail
assertTrue	assertTrue
N/A	assertThat
assertSame	assertSame
assertNull	assertNull
assertNotSame	assertNotSame
assertNotEquals	assertNotEquals
assertNotNull	assertNotNull
assertFalse	assertFalse
assertEquals	assertEquals
assertArrayEquals	assertArrayEquals
assertAll	N/A
assertThrows	N/A
assertTimeout	N/A
assertTimeoutPreemptively	N/A

Junit 5 Example

Junit 4 Example

Assumptions

JUnit 5	JUnit 4
assumeFalse	assumeFalse
	assumeNoException
	assumeNotNull
assumeThat	assumeThat
assumeTrue	assumeTrue

Junit 5 Example

Junit 4 Example

Tagging and Filtering

Junit 5 Example

Junit 4 Example

Nested Tests

Junit 5 Example

Junit 4 Example

Dependency Injection for Constructors and Methods

Junit 5 Example-1 Junit 5 Example-2 Junit 5 Example-3

Test Interfaces and Default Methods

Junit 5 Example-1 Junit 5 Example-2

Repeated Tests

Junit 5 Example

Junit 4 Example

Parameterized Tests

Junit 5 Example

Junit 4 Example-1 Junit 4 Example-2 Junit 4 Example-3

Extension Model

Junit 5 Example

Junit 4 Example-1 Junit 4 Example-2

Migration

See @EnableRuleMigrationSupport

Junit 5 Example