Question

Let’s say there is a super-class

class SuperClass {
    SuperClass(Foo foo) {
        this.foo = foo;
    }

    SuperClass() {
        this.foo = new DefaultFoo();
    }
}

And there’s a sub-class

class SubClass extends SuperClass {
     SubClass(Foo foo) {
        super(foo);
    }
}

The class under test is SubClass. I want to verify that SubClass' constructor is indeed invoking it’s superclass’ non-empty constructor. Is there any way to achieve this?

Answer 1

This should be possible with jmockit ( http://jmockit.googlecode.com ) by mocking superclass. Here is example

( from: https://groups.google.com/forum/?fromgroups=#!topic/jmockit-users/O-w9VJm4xOc )

public class TestClassUnderTest { 

     public class ClassUnderTest extends BaseClassForClassUnderTest 
     { 
        public ClassUnderTest(ISomeInterface si) 
        { 
           super(si); 
         } 
         //... 
      } 
@Test 
public void testSuperConstructorCall() 
{ 
    final ISomeInterface si = new ISomeInterface() 
    { 
    }; 

    Mockit.setUpMock(BaseClassForClassUnderTest.class, new Object() { 
        @Mock 
        public void $init(ISomeInterface si_param) 
        { 
            assertNotNull(si_param); 
            assertTrue(si_param == si); 
        } 
    }); 

    ClassUnderTest cut = new ClassUnderTest(si); 
} 

}