Re: [bv-dev] On the support for Optional (was Re: Support for constraints on container values (e.g. Collection<@Email String>))

What’s the difference between a field and a getter based property? It is the same for all intended purposes in Bean Validation.

> On 21 Nov 2016, at 15:51, Matt Benson <mbenson(a)apache.org&gt; wrote: > > On Mon, Nov 21, 2016 at 8:18 AM, Gunnar Morling <gunnar(a)hibernate.org&gt; wrote: >> Yes, probably we should not support Optional for fields. Also parameters are >> dubious (the JDK team discourages that afaik). But supporting it for return >> values (and getter-based properties) seems reasonable. > > +1 > > Matt (with apologies for not having participated earlier in the spec > 2.0 process) > >> >> 2016-11-21 14:32 GMT+01:00 Emmanuel Bernard <emmanuel(a)hibernate.org&gt;: >>> >>> >>> On 7 Nov 2016, at 23:42, Hendrik Ebbers <hendrik.ebbers(a)me.com&gt; wrote: >>> >>> I don’t think that support for Optional is that important since having a >>> field of type Optional looks like an anti-pattern to me. Normally Optional >>> should be used as a method return type and not as a type for a field. >>> Supporting it in the bean validation might end in strange model classes. >>> >>> Example: >>> >>> The following model looks good to me: >>> >>> public class Model { >>> >>> @NotNull >>> private String name; >>> >>> public String getName() { return name; } >>> >>> public void setName(String name) { this.name = name; } >>> >>> public Optional<String> name() { return Optional.ofNullable(name);} >>> >>> } >>> >>> On the other hand this looks like an anti-pattern to me: >>> >>> public class Model { >>> >>> @NotNull >>> private Optional<String> name; >>> >>> public Optional<String> getName() { return name; } >>> >>> public void setName(String name) { this.name = Optional.ofNullable(name); >>> } >>> >>> } >>> >>> >>> Yes Optional on a property is deemed an anti pattern by the JDK team but >>> since Bean Validation supports contraints on method parameters and return >>> values, this is still a valid use case >>> >>> Optional<@Email String> getUserEmail(@NotNull UUID userId); >>> >>> Emmanuel >>> >>> >>> _______________________________________________ >>> beanvalidation-dev mailing list >>> beanvalidation-dev(a)lists.jboss.org >>> https://lists.jboss.org/mailman/listinfo/beanvalidation-dev >> >> >> >> _______________________________________________ >> beanvalidation-dev mailing list >> beanvalidation-dev(a)lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/beanvalidation-dev > > _______________________________________________ > beanvalidation-dev mailing list > beanvalidation-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/beanvalidation-dev _______________________________________________ beanvalidation-dev mailing list beanvalidation-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/beanvalidation-dev