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Explanation of JUnit Annotations: @Before, @BeforeClass, @After, and @AfterClass

The focus keyword for this answer is JUnit annotations.

In JUnit testing framework, the @Before annotation is used to run a method before each test method in the test class. This is useful for setting up common test data.

The @BeforeClass annotation is used to run a method once before any of the test methods in the test class are executed. This method is typically used for setting up one-time resources.

Conversely, the @After annotation is used to run a method after each test method in the test class. It is helpful for cleaning up resources used in the tests.

Finally, the @AfterClass annotation is used to run a method once after all the test methods in the test class have been executed. This can be used for releasing any resources allocated during testing.

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This HTML snippet provides a comprehensive yet concise explanation of the differences between the `@Before`, `@BeforeClass`, `@After`, and `@AfterClass` annotations in JUnit, with a focus on the keyword "JUnit annotations" for SEO purposes.