1.2.4.4 使用Junit4运行JUnit Platfrom
The JUnitPlatform
runner is a JUnit 4 based Runner
which enables you to run any test whose programming model is supported on the JUnit Platform in a JUnit 4 environment — for example, a JUnit Jupiter test class.
Annotating a class with
@RunWith(JUnitPlatform.class)
allows it to be run with IDEs and build systems that support JUnit 4 but do not yet support the JUnit Platform directly.
Since the JUnit Platform has features that JUnit 4 does not have, the runner is only able to support a subset of the JUnit Platform functionality, especially with regard to reporting (see Display Names vs. Technical Names). But for the time being theJUnitPlatform
runner is an easy way to get started.
4.4.1. Setup
You need the following artifacts and their dependencies on the classpath. See Dependency Metadata for details regarding group IDs, artifact IDs, and versions.
Explicit Dependencies
junit-platform-runner
in test scope: location of theJUnitPlatform
runnerjunit-4.13.jar
in test scope: to run tests using JUnit 4junit-jupiter-api
in test scope: API for writing tests using JUnit Jupiter, including@Test
, etc.junit-jupiter-engine
in test runtime scope: implementation of theTestEngine
API for JUnit Jupiter
Transitive Dependencies
junit-platform-suite-api
in test scopejunit-platform-launcher
in test scopejunit-platform-engine
in test scopejunit-platform-commons
in test scopeopentest4j
in test scope
4.4.2. Display Names vs. Technical Names
To define a custom display name for the class run via @RunWith(JUnitPlatform.class)
simply annotate the class with @SuiteDisplayName
and provide a custom value.
By default, display names will be used for test artifacts; however, when the JUnitPlatform
runner is used to execute tests with a build tool such as Gradle or Maven, the generated test report often needs to include the technical names of test artifacts — for example, fully qualified class names — instead of shorter display names like the simple name of a test class or a custom display name containing special characters. To enable technical names for reporting purposes, simply declare the @UseTechnicalNames
annotation alongside @RunWith(JUnitPlatform.class)
.
Note that the presence of @UseTechnicalNames
overrides any custom display name configured via @SuiteDisplayName
.
4.4.3. Single Test Class
One way to use the JUnitPlatform
runner is to annotate a test class with @RunWith(JUnitPlatform.class)
directly. Please note that the test methods in the following example are annotated with org.junit.jupiter.api.Test
(JUnit Jupiter), not org.junit.Test
(JUnit 4). Moreover, in this case the test class must be public
; otherwise, some IDEs and build tools might not recognize it as a JUnit 4 test class.
import static org.junit.jupiter.api.Assertions.fail;
import org.junit.jupiter.api.Test;
import org.junit.platform.runner.JUnitPlatform;
import org.junit.runner.RunWith;
@RunWith(JUnitPlatform.class)
public class JUnitPlatformClassDemo {
@Test
void succeedingTest() {
/* no-op */
}
@Test
void failingTest() {
fail("Failing for failing's sake.");
}
}
4.4.4. Test Suite
If you have multiple test classes you can create a test suite as can be seen in the following example.
import org.junit.platform.runner.JUnitPlatform;
import org.junit.platform.suite.api.SelectPackages;
import org.junit.platform.suite.api.SuiteDisplayName;
import org.junit.runner.RunWith;
@RunWith(JUnitPlatform.class)
@SuiteDisplayName("JUnit Platform Suite Demo")
@SelectPackages("example")
public class JUnitPlatformSuiteDemo {
}
The JUnitPlatformSuiteDemo
will discover and run all tests in the example
package and its subpackages. By default, it will only include test classes whose names either begin with Test
or end with Test
or Tests
.
Additional Configuration OptionsThere are more configuration options for discovering and filtering tests than just
@SelectPackages
. Please consult the Javadoc of theorg.junit.platform.suite.api
package for further details.Test classes and suites annotated with
@RunWith(JUnitPlatform.class)
cannot be executed directly on the JUnit Platform (or as a "JUnit 5" test as documented in some IDEs). Such classes and suites can only be executed using JUnit 4 infrastructure.