This tutorial introduces the basic annotation supported in Junit 4.

import org.junit.*;
import static org.junit.Assert.*;
import java.util.*;
 
/**
 *
 *
 */
public class JunitTest1 {
 
    private Collection collection;
 
    @BeforeClass
    public static void oneTimeSetUp() {
        // one-time initialization code   
     System.out.println("@BeforeClass - oneTimeSetUp");
    }
 
    @AfterClass
    public static void oneTimeTearDown() {
        // one-time cleanup code
     System.out.println("@AfterClass - oneTimeTearDown");
    }
 
    @Before
    public void setUp() {
        collection = new ArrayList();
        System.out.println("@Before - setUp");
    }
 
    @After
    public void tearDown() {
        collection.clear();
        System.out.println("@After - tearDown");
    }
 
    @Test
    public void testEmptyCollection() {
        assertTrue(collection.isEmpty());
        System.out.println("@Test - testEmptyCollection");
    }
 
    @Test
    public void testOneItemCollection() {
        collection.add("itemA");
        assertEquals(1, collection.size());
        System.out.println("@Test - testOneItemCollection");
    }
}

Result

@BeforeClass - oneTimeSetUp
@Before - setUp
@Test - testEmptyCollection
@After - tearDown
@Before - setUp
@Test - testOneItemCollection
@After - tearDown
@AfterClass - oneTimeTearDown