Cartesian product of base and derived class parameter

[noviceamateur]

I have parameters in both the base and derived test classes. So I want the tests in derived class to run for the cartesian product of those.

Sample code -

@RunWith(Parameterized.class)
public class BaseTest {

  public BaseTest() {
  }

  @BeforeClass
  public static void setupbase() {
  }

  @Parameterized.Parameter(0)
  public String baseParam;

  @Parameterized.Parameters
  public static Collection<Object[]> data() {
    return Arrays.asList(new Object[][] {
        { "base1" }, { "base2" }
    });
  }
}



public class Test1 extends BaseTest {

  @BeforeClass
  public static void setup() {
  }

  @Parameterized.Parameter(0)
  public  String derivedParam;

  @Parameterized.Parameters
  public static Collection<Object[]> data() {
    return Arrays.asList(new Object[][] {
        { "derived1" }, { "derived2" }
    });
  }

  @Test
  public void testcase1() {
    System.out.println("Base Param = " + baseParam);
    System.out.println("Derived Param = " + derivedParam);
  }
}

The expected output -

Base Param = base1
Derived Param = derived1
Base Param = base1
Derived Param = derived2
Base Param = base2
Derived Param = derived1
Base Param = base2
Derived Param = derived2

Present error while running -

> java.lang.Exception: @Parameter(0) is used more than once (2).
> 
> 	at org.junit.runners.parameterized.BlockJUnit4ClassRunnerWithParameters.validateFields(BlockJUnit4ClassRunnerWithParameters.java:119)
> 	at org.junit.runners.BlockJUnit4ClassRunner.collectInitializationErrors(BlockJUnit4ClassRunner.java:129)
> 	at org.junit.runners.ParentRunner.validate(ParentRunner.java:416)
> 	at org.junit.runners.ParentRunner.<init>(ParentRunner.java:84)
> 	at org.junit.runners.BlockJUnit4ClassRunner.<init>(BlockJUnit4ClassRunner.java:65)
> 	at org.junit.runners.parameterized.BlockJUnit4ClassRunnerWithParameters.<init>(BlockJUnit4ClassRunnerWithParameters.java:27)
> 	at org.junit.runners.parameterized.BlockJUnit4ClassRunnerWithParametersFactory.createRunnerForTestWithParameters(BlockJUnit4ClassRunnerWithParametersFactory.java:16)
> 	at org.junit.runners.Parameterized.createRunnersForParameters(Parameterized.java:313)
> 	at org.junit.runners.Parameterized.<init>(Parameterized.java:248)
> 	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
> 	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
> 	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
> 	at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
> 	at org.junit.internal.builders.AnnotatedBuilder.buildRunner(AnnotatedBuilder.java:104)
> 	at org.junit.internal.builders.AnnotatedBuilder.runnerForClass(AnnotatedBuilder.java:86)
> 	at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
> 	at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:26)
> 	at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
> 	at org.junit.internal.requests.ClassRequest.getRunner(ClassRequest.java:33)
> 	at org.junit.internal.requests.FilterRequest.getRunner(FilterRequest.java:36)
> 	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:49)
> 	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
> 	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
> 	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
> 
> 
> java.lang.Exception: @Parameter(1) is never used.
> 
> 	at org.junit.runners.parameterized.BlockJUnit4ClassRunnerWithParameters.validateFields(BlockJUnit4ClassRunnerWithParameters.java:116)
> 	at org.junit.runners.BlockJUnit4ClassRunner.collectInitializationErrors(BlockJUnit4ClassRunner.java:129)
> 	at org.junit.runners.ParentRunner.validate(ParentRunner.java:416)
> 	at org.junit.runners.ParentRunner.<init>(ParentRunner.java:84)
> 	at org.junit.runners.BlockJUnit4ClassRunner.<init>(BlockJUnit4ClassRunner.java:65)
> 	at org.junit.runners.parameterized.BlockJUnit4ClassRunnerWithParameters.<init>(BlockJUnit4ClassRunnerWithParameters.java:27)
> 	at org.junit.runners.parameterized.BlockJUnit4ClassRunnerWithParametersFactory.createRunnerForTestWithParameters(BlockJUnit4ClassRunnerWithParametersFactory.java:16)
> 	at org.junit.runners.Parameterized.createRunnersForParameters(Parameterized.java:313)
> 	at org.junit.runners.Parameterized.<init>(Parameterized.java:248)
> 	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
> 	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
> 	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
> 	at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
> 	at org.junit.internal.builders.AnnotatedBuilder.buildRunner(AnnotatedBuilder.java:104)
> 	at org.junit.internal.builders.AnnotatedBuilder.runnerForClass(AnnotatedBuilder.java:86)
> 	at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
> 	at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:26)
> 	at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
> 	at org.junit.internal.requests.ClassRequest.getRunner(ClassRequest.java:33)
> 	at org.junit.internal.requests.FilterRequest.getRunner(FilterRequest.java:36)

Version - Junit 4.12

[marcphilipp]

I'm afraid that's not how Parameterized works. It will only find one of the @Parameters methods. Thus, you'll need to override the method in the subclass and compute the cartesian product yourself.

[noviceamateur]

Override which method in my subclass ?

Also, could this be taken up as a feature request in that case ?
Is it possible to do so in Junit5 ?

[kcooney]

Have you considered the Theories runner?