Issue with . in tag names

[fkrauthan]

I recently run into an issue where the XML I am consuming has tags like this: DISPLAYCONTACT.FIRSTNAME

My entity defines them like this:

    @XmlElement(true)
    @SerialName("DISPLAYCONTACT.FIRSTNAME")
    val firstName: String? = null,

in the same entity class all XML elements that do not have a . work fine and getting deserialized accordingly but all the once with . just getting ignored/skipped.

[fkrauthan]

The strange thing is the unknownChildHandler is called for example for DISPLAYCONTACT.FIRSTNAME even though it's clearly deserialized.

I've debuged even further and looked at the unknownChildHandler candidates list and noticed that ALL of my attributes with a . in serial name show up BUT only the last part. So DISPLAYCONTACT.FIRSTNAME is listed as FIRSTNAME in the candidates. Thats why It can not find a match.

[fkrauthan]

Ok for anyone that is running into the same issue a wrokaround is to use

@XmlSerialName("DISPLAYCONTACT.FIRSTNAME", "", "")

instead of

@SerialName("DISPLAYCONTACT.FIRSTNAME")

[pdvrieze]

I know what is going on. This is related to the mechanism that turns serialName values into tag names. For a type (rather than element) the serialName is the type name (if none is given with the annotation). Normally you don't want tag names with java packages in them (XML has namespaces for that).

This mechanism is implemented purely in the policy that you configure the format with. The default basically sees a . and assumes that this is a Kotlin type name and picks the final part only.

You can override this in serialNameToQName of the policy (you can extend DefaultXmlSerializationPolicy if you want). If you want (much) more control you can override effectiveName which is the user of that easier function (it is reasonably complex to deal with all kinds of special cases like built-in types as well as different policies for tags vs attributes).

The default implementation of serialNameToQName unfortunately provides no distinction between being called for the name of a type or for the name of an attribute. As names are part of the public API of serialization and a change in naming policy changes the names I can't really change the default without breaking peoples serialization. You could of course recognize specific names and special case them (positive or negative).

Unfortunately it is invisible to formats whether the @SerialName annotation was used. Which is the main reason that the @XmlSerialName annotation exists (btw. it is possible to process your own alternative annotations in effectiveName)

[pdvrieze]

As this is basically an edge case in a (best effort) heuristic to resolve a design limitation of the serialization framework I'm not sure what I can do, except suggesting to use the available mechanisms to either provide your own naming policy, or provide annotations where appropriate.

What I have done is to split serialNameToQName into two functions: serialTypeNameToQName and serialUseNameToQName which by default delegate to it. The default code calls these, so the policy can now differ based upon context without too much code being needed.

[fkrauthan]

Maybe this can be added to the documentation?