AEMContext not able to adapt to correct implementation class based on the models annotation resourceType property


We implemented an interface with multiple implementations. To determine the "closest" implementation to use when adapting to the interface we configured the resourceType properties on the implementation classes as described here.

This works on a AEM instance, but when we wrote a test to validate that the correct implementation is used with certain resourceTypes we noticed that the AEMContext is not behaving as we expected.
It seems it doens't take the resourceType property into account when deciding.
Right now when multiple implementations are found, it seems it just takes the first implementation that matches based on the alphabetical order of the class names.

Code example

Test Example


We assume that the reason for this behaviour is because the aem-mock still uses an old sling.api version 2.11.0 whereas AEM already uses the newer 2.18.4 version that includes this functionality.
Functionality is available version 2.13+ mvn dependency:tree

AEM 6.4 Sling Api bundle


Stefan Seifert
July 29, 2019, 1:43 PM

this should work OOTB - but: you have to make sure to reference a version of the sling models implementation JAR matching those of your AEM version. Sling Mocks (and AEM Mocks) is designed to work with multiple AEM versions, thus it references an older set of implementation JARs roughly from AEM 6.2. but it works if you reference newer set of the implementation JARs.

to make this easier you can the AEM dependencies for the AEM version you are using from these helper POMs:

this not only defines the version of the uber-jar, but also the fitting versions of the implementation JARs required by Sling/AEM Mocks.

Stefan Seifert
July 29, 2019, 1:44 PM
Ben Oeyen
July 29, 2019, 1:54 PM

Thx Stefan for the blazing fast reply!

We managed to get our tests working now, thanks for explaining.






Ben Oeyen