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

Am 21.11.2016 um 15:51 schrieb Matt Benson <mbenson(a)apache.org&gt;: On Mon, Nov 21, 2016 at 8:18 AM, Gunnar Morling <gunnar(a)hibernate.org <mailto:gunnar@hibernate.org>> 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 <mailto:beanvalidation-dev@lists.jboss.org> https://lists.jboss.org/mailman/listinfo/beanvalidation-dev <https://lists.jboss.org/mailman/listinfo/beanvalidation-dev>