[slf4j-dev] Fwd: investigation on the diffusion of innovation along with java releases

[Ceki Gülcü]

Hello Fernando,

As a widely used API, the challenge in changing SLF4J is preserving 100% 
compatibility. This was achieved by using Java 8 default implementation 
feature (widely used in the Logger interface). Given that SLF4J does not 
actually contain much code, we did not make use of lambdas internally. 
However, this will probably change as changes are made to the code.

Best regards,

--
Ceki

On 30/07/2019 09:45, Fernando Petrulio wrote:
> Dear Developers,
> 
> we are members of the ZEST research group (Zurich Empirical Software 
> Engineering Team) based at the University of Zurich and the Delft 
> University of Technology. We are conducting an investigation on the 
> diffusion of innovations and we focus on the adoption of new language 
> features. Our research is focused on how API producers adapt their 
> interfaces to introduce support for Java 8’s lambdas. During the course 
> of our investigation, we manually inspected SLF4J’s source code and 
> documentation to understand whether Java’s lambdas have widespread 
> adoption. We would like to have your feedback on our findings.
> 
> Our study focuses primarily on Functional Interfaces and Lambda 
> Expressions as these new features were introduced by the Java language 
> and adopted the Java JDK API, as they reduce implementation complexity, 
> improve readability, offer performance benefits and improve security 
> contextualization.
> Our analysis showed that though SLF4J 2.0 did not explicitly introduce 
> support for functional interfaces (e.g. by using the 
> @FunctionalInterface annotation). We noticed that the API does provide 
> compatibility with Java 8+ features, including lambda expressions (since 
> the API’s build platform is now on JDK 1.8). We would like to better 
> understand as to why no major change was necessitated to facilitate the 
> usage of lambda expressions with the API.
> 
> In most cases, developers choose to move to new releases to satisfy 
> particular dependency requirements, to take advantage of new Java 
> features (like streams and functional interfaces in the case of Java 8), 
> or just to standardize their implementation to align the API with the 
> Java JDK API. Can you provide us with more information about this?
> How did you and your team tackle the choice to change the version of 
> Java supported?
> Which factors did you take into account when doing this?
> Are there any documented sources (e.g. Jira tickets, or issue tracker 
> issues) about that discussion you can provide us with?
> Why were no explicit changes made to the interface to support lambda 
> expressions?
> Are there any future plans in place to make larger changes to the API 
> such that lambda expressions would be supported?
> 
> We thank you for taking the time to answer our questions. If you would 
> like to be posted about the results of this study, please let us know!
> 
> Kind Regards,
> Fernando Petrulio.
>