Re: [jackson-user] Are custom serializers cached?
On Mon, Apr 16, 2018 at 11:07 AM, Marcel Overdijk wrote: > I don’t *require* only 1 instance but want to avoid that many are created as > I do need to do some introspection if classes and want to cache that > information. > It is only an annotation in class level so that should be fine, or - maybe to > be sure - I could simply register the serializer via a simple module. In that case standard caching should work fine. If not, that would be a flaw. -+ Tatu +- > > > Cheers, > Marcel > > -- > You received this message because you are subscribed to the Google Groups > "jackson-user" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to jackson-user+unsubscr...@googlegroups.com. > To post to this group, send email to jackson-user@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "jackson-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to jackson-user+unsubscr...@googlegroups.com. To post to this group, send email to jackson-user@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [jackson-user] Are custom serializers cached?
I don’t *require* only 1 instance but want to avoid that many are created as I do need to do some introspection if classes and want to cache that information. It is only an annotation in class level so that should be fine, or - maybe to be sure - I could simply register the serializer via a simple module. Cheers, Marcel -- You received this message because you are subscribed to the Google Groups "jackson-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to jackson-user+unsubscr...@googlegroups.com. To post to this group, send email to jackson-user@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [jackson-user] Are custom serializers cached?
On Sun, Apr 15, 2018 at 10:01 AM, Marcel Overdijk wrote: > Hi, > > When I have a custom `JsonSerializer` defined via @JsonSerialize does it it > create only 1 instance of the `JsonSerializer` or multiple? > > > @JsonSerialize(using = JsonapiDocument.JsonapiDocumentSerializer::class) > class JsonapiDocument > > I need to introspect the class to be serialized and want to cache this > information in the Serializer. > But to do this I want to make sure that only 1 instance of the Serializer is > created? > > > In the apidocs of the `JsonSerializer` I could't find any information / > statement regarding this. If I understand your case correctly, only one instance is created and cached for lookup purposes. This assumes that annotation is on class; if annotation is on a property I'd have to check to make sure whether caching is involved at all. However: lookup and caching is just the initial part. Many (de)serializers are further configured by contextual information (mostly annotations on property accessor(s)) -- if serializer implements `ContextualSerializer`, then its `createContextual(...)` method is called when serializer is needed for specific property (and once for root value, if used for root value). So, only one instance should be created. I would not count on this as anything more than as implementation detail, however -- cache sizes are often bounded (... and in this particular case, will be bounded in Jackson 3.0; 2.x does not limit it unfortunately) so there is no strict guarantee that only one instance is ever created. If such a guarantee is required, it could be achieved in at least 2 ways: 1. Canonicalize in `createContextual()` (that is, verify that `this` is singleton instance; or if not, return that singleton instance) 2. Use `Module` for providing serializer instead. and I guess I would go with (1). But this is only assuming it is critical that just one serializer instance is used. -+ Tatu +- -- You received this message because you are subscribed to the Google Groups "jackson-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to jackson-user+unsubscr...@googlegroups.com. To post to this group, send email to jackson-user@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[jackson-user] Are custom serializers cached?
Hi, When I have a custom `JsonSerializer` defined via @JsonSerialize does it it create only 1 instance of the `JsonSerializer` or multiple? @JsonSerialize(using = JsonapiDocument.JsonapiDocumentSerializer::class) class JsonapiDocument I need to introspect the class to be serialized and want to cache this information in the Serializer. But to do this I want to make sure that only 1 instance of the Serializer is created? In the apidocs of the `JsonSerializer` I could't find any information / statement regarding this. Br, Marcel -- You received this message because you are subscribed to the Google Groups "jackson-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to jackson-user+unsubscr...@googlegroups.com. To post to this group, send email to jackson-user@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
