[Hawkular-dev] @Null / @NotNull

[John Sanda]

How about using the Optional class introduced in Java instead of null? Not only does it provide documentation like the annotations do, but Optional also provides a rich API that the annotations do not. If you are not familiar with Optional, this article[1] is a good overview.

[1] http://www.oracle.com/technetwork/articles/java/java8-optional-2175753.html <http://www.oracle.com/technetwork/articles/java/java8-optional-2175753.html>
> On Mar 2, 2015, at 5:27 AM, Heiko W.Rupp <hrupp at redhat.com> wrote:
> 
> Hey,
> 
> as we were having a discussion this morning on #hawkular-dev about null
> 
> I think we should start (on top of writing more JavaDoc) using
> annotations to mark methods and method parameters that
> allow being null / not null and if they may return null or not.
> 
> This is especially important on API classes(*1), that may be 
> consumed by 3rd parties that may or may not have insight
> into source of the implementation (on top of that, such annotations
> are an enhancement of the API contract).
> 
> I know we have been talking about that in the past without
> no real result. Luckily since then JSR 308 has been
> marked as final and thus a standard exists, that includes such
> annotations (+ a checking framework, + tooling to retroactively add
> such annotations to existing source).
> 
> See http://types.cs.washington.edu/checker-framework/
> and http://mvnrepository.com/artifact/org.checkerframework for mvn artifacts
> 
> http://mvnrepository.com/artifact/org.checkerframework/checker-qual/1.8.10 <- annotations
> http://types.cs.washington.edu/checker-framework/current/api/ <- Javadoc
> 
> Another option are the org.jetbrains versions of the annotations, which are around for a while.
> 
> If we only care about documentation, but not compile time and/or static analysis, we can also
> use the ones from BeanValidation, which live under the javax package spaces (iirc). *2
> 
> Here is a more complete list of frameworks
> http://stackoverflow.com/questions/4963300/which-notnull-java-annotation-should-i-use
> 
> 
> 
> 
> *1) Java and REST
> *2) BV may be a good idea for more complex input like in alert definition
> 
> 
> 
> 
> _______________________________________________
> hawkular-dev mailing list
> hawkular-dev at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/hawkular-dev

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/hawkular-dev/attachments/20150302/0d23fcbf/attachment.html