Explaining the Difference Between JUnit 4 and JUnit 5

JUnit is a popular Java testing framework used by developers to write and run unit tests. Here are some key differences between JUnit 4 and JUnit 5:

1. Architecture:

JUnit 4 follows a more class-based architecture where test cases are written as methods inside test classes. JUnit 5 introduces a more modular and flexible approach with the introduction of annotations such as @Test, @BeforeEach, @AfterEach, etc.

2. Extension Model:

JUnit 4 uses a rule-based model for extending test behavior while JUnit 5 introduces a more powerful extension model with annotations like @ExtendWith and interfaces like TestInstancePostProcessor.

3. Assertions:

JUnit 5 provides a new set of assertions in the org.junit.jupiter.api.Assertions class that offers more flexibility and readability compared to JUnit 4's static methods for assertions.

4. Platform Support:

JUnit 5 is designed with better support for Java 8 features, including lambda expressions and annotations. It also provides support for running tests in different environments through its JUnit Platform.

5. Parameterized Tests:

Parameterized tests in JUnit 4 require the use of special runners or custom coding, while JUnit 5 simplifies parameterized testing with the @ParameterizedTest annotation.