AnotherClass.java

public class AnotherClass {

@TestedBy (class="NullVerifier" method="shouldNotreturnNull")
public String anotherMethod(String param);
}

ImplOne.java

public class ImpleOne implements IunderTest {

public String methodOne() {
//implementation....
}
}

ImplTwo.java

public class ImpleTwo implements IunderTest {

public String methodOne() {
//implementation....
}
}

IUnderTest.java

public interface IunderTest {

@TestedBy (class="TestClass" method="pippo")
@TestedBy (class="NullVerifier" method="shouldNotreturnNull")
public String methodOne();
}

NullVerifier.java

package it.javalinux.testedby.commontests;

import static it.javalinux.testedby.factories.ClassUnderTestInstanceFactory.invokeMethodUnderTest;


public class NullVerifier {
@Test
public void shouldNotreturnNull() {

Object result = invokeMethodUnderTest();
//assertions on result to be not null

}

}
}

TestClass.java

import static it.javalinux.testedby.factories.ClassUnderTestInstanceFactory.createInstance;

public class TestClass {

@Test
public void pippo() {

IunderTest ut= createInstance(IunderTest.class);
String result = ut.methodOne();
//assertions on result
}
}