Jaka jest różnica między użyciem JUnit @BeforeClass i Spring @TestExecutionListener beforeTestClass (TestContext testContext) „hook”? Jeśli istnieje różnica, która z nich będzie używana w jakich okolicznościach?

Zależności Mavena:
spring-core: 3.0.6.RELEASE
spring-context: 3.0.6.RELEASE
test wiosenny: 3.0.6.RELEASE
spring-data-commons-core: 1.2.0.M1
spring-data-mongodb: 1.0.0.M4
mongo-java-driver: 2.7.3
junit: 4.9
cglib: 2.2

Korzystanie z adnotacji JUnit @BeforeClass:

import org.junit.BeforeClass;
import org.junit.Test;
import org.junit.Assert;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.AbstractJUnit4SpringContextTests;

@ContextConfiguration(locations = { "classpath:test-config.xml" })
public class TestNothing extends AbstractJUnit4SpringContextTests {

    @Autowired
    PersonRepository repo;

    @BeforeClass
    public static void runBefore() {
        System.out.println("@BeforeClass: set up.");
    }

    @Test
    public void testInit() {
        Assert.assertTrue(repo.findAll().size() == 0 );
    }
}

=> @BeforeClass: set up.
=> Process finished with exit code 0

Używanie haka sprężynowego:

(1) Zastąp przedtemTestClass (TextContext testContext):

import org.springframework.test.context.TestContext;
import org.springframework.test.context.support.AbstractTestExecutionListener;

public class BeforeClassHook extends AbstractTestExecutionListener {

    public BeforeClassHook() { }

    @Override
    public void beforeTestClass(TestContext testContext) {
        System.out.println("BeforeClassHook.beforeTestClass(): set up.");
    }
}

(2) Użyj adnotacji @TestExecutionListeners:

import org.springframework.test.context.TestExecutionListeners;  
// other imports are the same    

@ContextConfiguration(locations = { "classpath:test-config.xml" })
@TestExecutionListeners(BeforeClassHook.class)
public class TestNothing extends AbstractJUnit4SpringContextTests {

    @Autowired
    PersonRepository repo;

    @Test
    public void testInit() {
        Assert.assertTrue(repo.findAll().size() == 0 );
    }
}

=> BeforeClassHook.beforeTestClass(): set up.
=> Process finished with exit code 0