Using parameterized JUnit tests with the play! framework - junit

Question

I want to use parameterized JUnit tests on a play! framework (1.2.5) application.
This is my very simple test example:
import java.util.Arrays;
import java.util.List;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;
import play.test.FunctionalTest;
#RunWith(Parameterized.class)
public class ParameterizedExampleTest extends FunctionalTest {
private int i;
#Parameters
public static List<Object[]> parameters() {
return Arrays.asList(new Object[][] {{1},{2},{3}});
}
public ParameterizedExampleTest(int i) {
this.i = i;
}
#Test
public void someTest() {
System.out.println("i is " + i);
}
}
When I run the test, I get an IllegalArgumentException telling me "Test class can only have one constructor". I perfectly agree with that as FunctionalTest extends BaseTest which has a #RunWith(PlayJUnitRunner.class) annotation and the PlayJUnitRunner has a constructor.
Any help welcome!

Answer 1

I found a rather nice solution:
import java.util.Arrays;
import java.util.List;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameter;
import org.junit.runners.Parameterized.Parameters;
import play.test.FunctionalTest;
#RunWith(Parameterized.class)
public class ParameterizedExampleTest extends FunctionalTest {
#Parameter(0)
public int i;
#Parameters
public static List<Object[]> parameters() {
return Arrays.asList(new Object[][] {{1},{2},{3}});
}
#Test
public void someTest() {
System.out.println("i is " + i);
}
}
You have to mark the parameters with the #Parameter(...) Annotation and the number of the parameter in the parameters array. No constructor is needed hence it runs smoothly with play.
Drawback: You will need JUnit 4.11 as this feature is not implemented in 4.10 which is what play (1.2.5) comes with.