Trying to Mock an abstract class inside another abstract class

[Thang]

Hi folks, 

I'm trying to mock an inner abstract class contained in an abstract outer class. I have been trying to do something like this:

DoFn<String, ETEvent>.ProcessContext mockContext =
    mock(DoFn.ProcessContext.class, withSettings().stubOnly().outerInstance(DoFn.class));

However I get the following exception:

org.mockito.exceptions.base.MockitoException: 

Mockito cannot mock this class: class com.google.cloud.dataflow.sdk.transforms.DoFn$ProcessContext.

Mockito can only non-private & non-final classes.

If you're not sure why you're getting this error, please report to the mailing list.

Java               : 1.8

JVM vendor name    : Oracle Corporation

JVM vendor version : 25.91-b14

JVM name           : Java HotSpot(TM) 64-Bit Server VM

JVM version        : 1.8.0_91-b14

JVM info           : mixed mode

OS name            : Mac OS X

OS version         : 10.11.6

Underlying exception : java.lang.IllegalStateException: Unknown type variable: OutputT

I imagine this has to do with the outer abstract class, but I was curious if mocking this inner abstract class is possible. Whether or not I should actually be doing this is another question. 

Here's a link to the class definition: ProcessContext

And here's the maven dependency if anyone wants to try this: 

<dependency>
  <groupId>com.google.cloud.dataflow</groupId>
  <artifactId>google-cloud-dataflow-java-sdk-all</artifactId>
  <version>1.8.0</version>
</dependency> 

Thanks for reading,

Thang

[Eric Lefevre-Ardant]

Hey Thang,

I was not sure what to expect there, so tried it out.

For me, everything works well. I tried both with Mockito 2.0.2-beta and 1.10.19.

I only tried both with my own abstract outer+inner classes and with DoFn.ProcessContext (thanks for the detailed context, BTW).

I can definitely called mock() on them and also call their (mocked) methods.

One difference, though, is that I used Object in place of the ETEvent class that you have:

DoFn<String, Object>.ProcessContext mockContext =

                mock(DoFn.ProcessContext.class, withSettings().stubOnly().outerInstance(DoFn.class));

The error message from Mockito (Unknown type variable: OutputT) makes me think that this is the real issue, although I cannot explain why.

Try with Object, and see how it goes?

--
You received this message because you are subscribed to the Google Groups "mockito" group.
To unsubscribe from this group and stop receiving emails from it, send an email to mockito+unsubscribe@googlegroups.com.
To post to this group, send email to moc...@googlegroups.com.
Visit this group at https://groups.google.com/group/mockito.
To view this discussion on the web visit https://groups.google.com/d/msgid/mockito/a356bfed-b0bd-4640-9373-33c5d5b71a58%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[Brice Dutheil]

Hey Thang, thanks for reporting!

Thanks Eric for confirming this is a bug in 2.1.0, this looks like to be an issue with bytebuddy. Anyway I will create a bug on mockito to track it.

Next time please don't forget the full stack trace and mockito version ;) 

I reproduced the issue with simpler code to narrow down the issue. Here's the issue : https://github.com/mockito/mockito/issues/699

 

-- Brice

To view this discussion on the web visit https://groups.google.com/d/msgid/mockito/CAPffK0FAiGGfEQCn4AGex3uyLsEmxKaeUcNG75HRSA3OpYCizA%40mail.gmail.com.