Get name of currently executing test in JUnit 4

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In JUnit 3, I could get the name of the currently running test like this:

public class MyTest extends TestCase
{
    public void testSomething()
    {
        System.out.println("Current test is " + getName());
        ...
    }
}

which would print "Current test is testSomething".

Is there any out-of-the-box or simple way to do this in JUnit 4?

Background: Obviously, I don't want to just print the name of the test. I want to load test-specific data that is stored in a resource with the same name as the test. You know, convention over configuration and all that.

16 Answers

A convoluted way is to create your own Runner by subclassing org.junit.runners.BlockJUnit4ClassRunner.

You can then do something like this:

public class NameAwareRunner extends BlockJUnit4ClassRunner {

    public NameAwareRunner(Class<?> aClass) throws InitializationError {
        super(aClass);
    }

    @Override
    protected Statement methodBlock(FrameworkMethod frameworkMethod) {
        System.err.println(frameworkMethod.getName());
        return super.methodBlock(frameworkMethod);
    }
}

Then for each test class, you'll need to add a @RunWith(NameAwareRunner.class) annotation. Alternatively, you could put that annotation on a Test superclass if you don't want to remember it every time. This, of course, limits your selection of runners but that may be acceptable.

Also, it may take a little bit of kung fu to get the current test name out of the Runner and into your framework, but this at least gets you the name.

JUnit 4 does not have any out-of-the-box mechanism for a test case to get it’s own name (including during setup and teardown).

String testName = null;
StackTraceElement[] trace = Thread.currentThread().getStackTrace();
for (int i = trace.length - 1; i > 0; --i) {
    StackTraceElement ste = trace[i];
    try {
        Class<?> cls = Class.forName(ste.getClassName());
        Method method = cls.getDeclaredMethod(ste.getMethodName());
        Test annotation = method.getAnnotation(Test.class);
        if (annotation != null) {
            testName = ste.getClassName() + "." + ste.getMethodName();
            break;
        }
    } catch (ClassNotFoundException e) {
    } catch (NoSuchMethodException e) {
    } catch (SecurityException e) {
    }
}

In JUnit 5 TestInfo acts as a drop-in replacement for the TestName rule from JUnit 4.

From the documentation :

TestInfo is used to inject information about the current test or container into to @Test, @RepeatedTest, @ParameterizedTest, @TestFactory, @BeforeEach, @AfterEach, @BeforeAll, and @AfterAll methods.

To retrieve the method name of the current executed test, you have two options : String TestInfo.getDisplayName() and Method TestInfo.getTestMethod().

To retrieve only the name of the current test method TestInfo.getDisplayName() may not be enough as the test method default display name is methodName(TypeArg1, TypeArg2, ... TypeArg3).
Duplicating method names in @DisplayName("..") is not necessary a good idea.

As alternative you could use TestInfo.getTestMethod() that returns a Optional<Method> object.
If the retrieval method is used inside a test method, you don't even need to test the Optional wrapped value.

import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.TestInfo;
import org.junit.jupiter.api.Test;

@Test
void doThat(TestInfo testInfo) throws Exception {
    Assertions.assertEquals("doThat(TestInfo)",testInfo.getDisplayName());
    Assertions.assertEquals("doThat",testInfo.getTestMethod().get().getName());
}

JUnit 5 via ExtensionContext

Advantage:

You get to have the added functionalities of ExtensionContext by overriding afterEach(ExtensionContext context).

public abstract class BaseTest {

    protected WebDriver driver;

    @RegisterExtension
    AfterEachExtension afterEachExtension = new AfterEachExtension();

    @BeforeEach
    public void beforeEach() {
        // Initialise driver
    }

    @AfterEach
    public void afterEach() {
        afterEachExtension.setDriver(driver);
    }

}
public class AfterEachExtension implements AfterEachCallback {

    private WebDriver driver;

    public void setDriver(WebDriver driver) {
        this.driver = driver;
    }

    @Override
    public void afterEach(ExtensionContext context) {
        String testMethodName = context.getTestMethod().orElseThrow().getName();
        // Attach test steps, attach scsreenshots on failure only, etc.
        driver.quit();
    }

}

I'd suggest you decouple the test method name from your test data set. I would model a DataLoaderFactory class which loads/caches the sets of test data from your resources, and then in your test case cam call some interface method which returns a set of test data for the test case. Having the test data tied to the test method name assumes the test data can only be used once, where in most case i'd suggest that the same test data in uses in multiple tests to verify various aspects of your business logic.

I have a Junit4 test class that extends TestCase so the example with @Rule didn't work (as mentioned in other answers).

However, if your class extends TestCase you can use getName() to get the current test name so this works:

@Before
public void setUp() {
  System.out.println("Start test: " + getName());
}

@After
public void tearDown() {
  System.out.println("Finish test: " + getName());
}

I usually use something like this:

/** Returns text with test method name
    @param offset index of method on call stack to print, 1 for a caller of this method.
    */
    static String getName(int offset)
    { 
        Throwable t = new Throwable();
        t.fillInStackTrace();
        return 
               t.getStackTrace()[offset].getMethodName()+":"+t.getStackTrace()[offset].getLineNumber(); 
    };

This is exactly what Exception do use when printing stack trace. Depending on the exact context You may have to figure out correct offset value. It is crude and primitive tough and is not using any fancy modern futures.

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